New species and new distributional records of the hygropetric water scavenger beetle genus Oocyclus Sharp (Coleoptera, Hydrophilidae) from the Brazilian Shield

Abstract

Nine new species of the water scavenger beetle genus Oocyclus Sharp, 1882 are described from the Brazilian Shield: O. ecolab sp. n., O. espinhacu sp. n., O. giganteus sp. n., O. humboldti sp. n., O. lacia sp. n., O. ovalis sp. n., O. sulcatus sp. n., O. thrixdiastematus sp. n., and O. thysanus sp. n. New locality records are provided for four species previously known from Brazil: O. rotundus Clarkson & Short, 2012, O. pilosus Jordão, Clarkon & Ferreira-Jr, 2018, O. xanthus Clarkson & Short, 2012 and O. yubai Clarkson & Short, 2012. All species are associated with rock-face seepages such as wet rocks, waterfalls, and seepages. An updated key to the Brazilian species of Oocyclus is provided.

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ZOOTAXA
ISSN 1175-5326 (print edition)
ISSN 1175-5334 (online edition)
Accepted by M. Toledo: 3 Dec. 2021; published: 6 Jan. 2022 275
Zootaxa 5087 (2): 275–305
https://www.mapress.com/zt/
Copyright © 2022 Magnolia Press Article
https://doi.org/10.11646/zootaxa.5087.2.3
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New species and new distributional records of the hygropetric water scavenger
beetle genus Oocyclus Sharp (Coleoptera, Hydrophilidae) from the Brazilian
Shield
JANDERSON BATISTA R. ALENCAR¹, ANDREW EDWARD Z. SHORT² & NEUSA HAMADA¹
¹Coordenação de Biodiversidade, Programa de Pós-Graduação em Entomologia (PPGEnt), Instituto Nacional de Pesquisas da
Amazônia (INPA), Av. André Araújo 2936, CEP 69067-375, Manaus, AM, Brasil.
�
jandersonrn@gmail.com
²Division of Entomology, Biodiversity Institute & Department of Ecology & Evolutionary Biology, University of Kansas, 1501 Crestline
Drive, Suite 140, Lawrence, KS 66045, U.S.A.
�
aezshort@ku.edu
Alencar: https://orcid.org/0000-0001-9482-7866
Short: https://orcid.org/0000-0002-7467-7116
Hamada: https://orcid.org/0000-0002-3526-5426
Abstract
Nine new species of the water scavenger beetle genus Oocyclus Sharp, 1882 are described from the Brazilian Shield: O.
ecolab sp. n., O. espinhacu sp. n., O. giganteus sp. n., O. humboldti sp. n., O. lacia sp. n., O. ovalis sp. n., O. sulcatus sp.
n., O. thrixdiastematus sp. n., and O. thysanus sp. n. New locality records are provided for four species previously known
from Brazil: O. rotundus Clarkson & Short, 2012, O. pilosus Jordão, Clarkon & Ferreira-Jr, 2018, O. xanthus Clarkson &
Short, 2012 and O. yubai Clarkson & Short, 2012. All species are associated with rock-face seepages such as wet rocks,
waterfalls, and seepages. An updated key to the Brazilian species of Oocyclus is provided.
Key words: Aquatic beetles, taxonomy, Neotropical Region, rock-face seepages
Introduction
The water scavenger beetle genus Oocyclus Sharp, 1882 (Coleoptera: Hydrophilidae: Laccobiini) contains more than
65 described species distributed throughout the Indomalayan (20 spp.) and Neotropical (45 spp.) regions (Clarkson
& Short 2012; Hansen 1999; Jordão et al. 2018; Short et al. 2013; Short & Fikáček 2011; Short & Jia 2011; Short
& Kadosoe 2011). The knowledge of the diversity and distribution of Oocyclus in South America has grown sub-
stantially in the last 12 years, currently there are 35 described species know from the continent, 15 of which are
reported from Brazil (Clarkson & Short 2012; García-Hernández 2009; Jordão et al. 2018; Short et al. 2013; Short
& García 2010; Short & Kadosoe 2011). All known species of the genus occur exclusively in hygropetric habitats
which includes rock-face seepages, the spray zones of waterfalls, and different kinds of vertical surfaces with water.
These hygropetric niches are among the most poorly known aquatic habitats (Short 2018). Here, new records and
descriptions of nine new species are presented from extensive surveys of rock-face seepages in the Brazilian Shield.
We also provide a checklist and updated key to species from Brazil, modified from Clarkson & Short (2012).
Material and methods
This study is based on more than 2,900 specimens collected exclusively in rock-face seepages in the Brazilian
Shield (center, northeast and southeast of the country) between 2014 and 2020 (Figs. 1a–d).
Specimens were photographed using a Leica DFC 420 video camera attached to a Leica M165C stereomicro-
scope using a LED illumination dome (Kawada & Buffington 2016). Each image was constructed using between
15 and 30 images which were stacked using Helicon Focus® (version 6.7.1 Pro). Photographs were assembled into
plates using Adobe Photoshop®. Genitalia were dissected out and cleared in cold 10% KOH and stored in a micro-
vial containing glycerin pinned beneath the specimen. The specimens were preserved in ethanol (80–90%).
In the descriptions, the total body length divided by the largest body width (abbreviated as TL/GW) was used to

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describe the body form. The morphological terminology follows Hansen (1991) except that we use the terms meso-
and metaventrite instead of meso- and metasternum. The identification of the species was based on Clarkson &
Short (2012), Jordão et al. (2018), Short et al. (2013), and Short & García (2010) as well as by comparison with type
material deposited in the SEMC and USNM. The distribution maps were generated using QGIS 3.10.9-A Coruña
and SimpleMappr (Shorthouse 2010).
Types and voucher specimens are deposited in the following institutions:
INPA Invertebrate Collection of the Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil (M.
Oliveira, curator)
SEMC University of Kansas, Lawrence, USA (A.E.Z. Short, curator)
FIGURE 1. Rock-face seepages of Oocyclus species. (a) collection sites in Brazil included in this article, (b) spray zones of
waterfalls, (c) vertical surfaces with water, (d) rock-face seepages with green algae.
Taxonomic treatment
Oocyclus ecolab sp. n.
(Figs. 2a–e, 11a, 14)
Type material. Holotype (male): “BRASIL: MINAS GERAIS, Itabirito, Córrego prox. a Fazenda Velha, long -
43.8091, lat -20.2991, 862 m a.s.l., rock-face seepages 20.vi.2019, leg. J.B.R. Alencar” (INPA, Coleoptera, in alcohol).

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 277
Diagnosis. Medium-sized species. Pronotum with rounded posterolateral margins. Elytra surface even, with
rows of fine systematic punctures bearing short setae, interrupted in some regions along their length; lateral rows
very indistinct, blending with surrounding ground punctation. Elytral sutural interval not raised. Prosternum with
two anteromedial spine-like setae. Abdominal ventrites dark brown, not paler than thoracic ventrites, in strong con-
trast to yellow to light brown legs and pseudoepipleura.
Adult. Body length 4.2 mm (n= 1); TL/GW 1.76 mm. General body shape broadly oval, slightly convex.
Color. Dorsum black (Fig. 2a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending ca. 4/5 along lateral margin. Elytra with irregular patches of bronze or green iri-
descence; with row of rounded black [=without sheen] spots along suture. Each elytron with two small circular pale
spots: anterior pale spot on distal third, about twice as far from suture than posterior spot; posterior spot situated on
distal quarter. Maxillary and labial palps yellow. Ventral face of head dark brown to black. Lateral margins of pro-
sternum yellowish brown; pseudoepipleura and epipleura yellowish brown. Thorax dark brown to black ventrally.
Legs light brown to yellow, except for dark brown coxae and base of femora. Abdominal ventrites dark brown, with
slightly lighter posterior margins on ventrites 1–4, sometimes with pale patches laterally on ventrites 2–3.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width
of one puncture (Fig. 2d). Ground punctation on labrum denser than on clypeus, distance between punctures 0.5–
1.5× width of one puncture; with few distinct systematic punctures medially. Labrum bearing short setae. Clypeus
with several scattered indistinct systematic punctures laterally; bearing short setae. Frons with irregular row of
systematic punctures toward the median plane of each eye and few fine setae around ocular suture. Maxillary palps
shorter than width of labrum; segment 3 shorter than segment 2; apical segment longer than penultimate segment.
Labial palps about two-thirds as long as width of mentum. Mentum smooth, with scattered coarse punctures; sub-
quadrate, anterior margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra evenly distributed and moderately coarse (Figs. 2a, c, d).
Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; anterior and
posterior series each forming irregular field. Lateral margins of pronotum with fine setae distributed along its length,
being more densely pubescent in anterior half. Pronotal posterolateral angles rounded. Sutural interval on elytra
not raised. Elytral interval with weak or non-existent pubescence in ground punctation (e.g. Figs. 12a, c, d). Elytra
with five rows of systematic punctures: rows 1 and 2 each represented by punctures not larger that surrounding
punctuation and at about same spacing; rows 3–5 with punctures not larger than surrounding ground punctuation
and as such hardly distinguishable. Elytral surface without any depression. Humeral region (in frontal view) without
antero-medial elevation. Elytral margins with short spine-like setae equally spaced along its length. Prosternum with
clearly defined median carina; slightly elevated anteromedially (Fig. 2e); elevated region with two spine-like setae.
Elevated process of mesoventrite wide and elongate, about twice as long as wide; slightly raised anteriorly; with
3–4 coarse spine-like setae. Metaventrite with oval glabrous area posteromedially, slightly longer than wide; length
of glabrous area about two-thirds length of metaventrite. Procoxae with fine short pubescence and set with coarse,
short spine-like setae; grouped on basal half. Protibiae each with 6–7 spine-like setae on dorsal face. Meso- and
metafemora with scattered punctures bearing short thickened, spine-like setae.
Abdomen. Ventrites covered with setae of varying lengths; ventrites 1–4 with scattered, long setae, distinctly
longer than longest setae on metaventrite, ventrite 5 more densely pubescent (Fig. 2b). Aedeagus: outer margin of
parameres weakly sinuous, gradually tapering to apex, curving inward; inner margin, sinuous, gradually tapering
towards apex (dorsal view); median lobe shorter than parameres, without apical hook. Gonopore located at four-
fifths length of median lobe. Basal piece rounded (Fig. 11a).
Etymology. The specific epithet ecolab is derived from the acronym of the Community Ecology Lab of the
Universidade Federal do Amazonas, in Brazil. It is a tribute to all the support received for the development of this
work. To be treated as a noun in apposition.
Distribution. Brazil (Minas Gerais) (Fig. 14).
Remarks. This species shares several diagnostic features with O. caparao Clarkson & Short, 2012: non-pale
abdominal ventrites, elytral suture not raised, elytra surface with rows of systematic punctures bearing short setae.
However, O. caparao differs in that its elytral surface has faint, very shallowly impressed longitudinal grooves near
the suture and the prosternum usually set with six spine-like setae, while longitudinal grooves are absent and the
prosternum bears two spine-like setae in O. ecolab sp. n.

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FIGURE 2. Oocyclus ecolab sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d), arrow indicates pros-
ternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 279
Oocyclus espinhacu sp. n.
(Figs. 3a–e, 11b, 14)
Type material. Holotype (male): “BRASIL: MINAS GERAIS, Parque Estadual Grão Mogol, stream near the
archaeological site, long -42.943556 lat -16.618111, 719 m a.s.l., rock-face seepages, 29.iv.2019, leg. J.B.R. Alen-
car” (INPA, Coleoptera, in alcohol). Paratypes (339 exs.): BRAZIL: Minas Gerias: Same data as holotype (24
exs. INPA; 10 exs. SEMC, in alcohol); except: “Waterfall of Mirante, long -42.899694, lat -16.576639, 821 m
a.s.l., rock-face seepages, 27.iv.2019, leg. J.B.R. Alencar” (1 ex. INPA, in alcohol); “Waterfall da Bocaina, long
-42.837083, lat -16.301167, 669 ma.s.l., rock-face seepages, 28.iv.2019, leg. J.B.R. Alencar” (21 exs. INPA, in
alcohol); “Waterfall of Almas, long -42.931194, lat -16.618139, 691 m a.s.l., rock-face seepages, 29.iv.2019, leg.
J.B.R. Alencar” (16 exs. INPA, in alcohol); “Waterfall of Coronhas, long -42.885194 lat -16.522417, 792 m a.s.l.,
rock-face seepages, 30.iv.2019, leg. J.B.R. Alencar” (71 exs. INPA, in alcohol); “PARNA Sempre Vivas, Waterfall
of Felipes, long -43.703639, lat -17.907472, 1090 m a.s.l., rock-face seepages, 24.iv.2019, leg. J.B.R. Alencar”
(2 exs. INPA, in alcohol); “Stream southwest of camp, long -43.773861, lat -17.924444, 1259 m a.s.l., rock-face
seepages, 23.iv.2019, leg. J.B.R. Alencar” (15 exs. INPA, in alcohol); “Curimataí, Waterfall of Rio Curimataí, long
-43.946806, lat -17.87825, 625 m a.s.l., vertical surfaces with water, 23.vi.2019, leg. J.B.R. Alencar” (9 exs. INPA,
in alcohol); “PARNA Serra do Cipó, Waterfall of Andorinhas, long -43.491472, lat -19.237611, 1028 m a.s.l.,
vertical surfaces with water, 10.iv.2019, leg. J.B.R. Alencar” (24 exs. INPA, in alcohol); “Waterfall of Tombador,
long -43.539833, lat -19.335639, 867 m a.s.l., vertical surfaces with water, 12.iv.2019, leg. J.B.R. Alencar” (24
exs. INPA, in alcohol); “Waterfall of Gavião, long -43.555806, lat -19.335639, 844 m a.s.l., vertical surfaces with
water, 12.iv.2019, leg. J.B.R. Alencar” (24 exs. INPA, in alcohol); “Conceição do Mato Dentro, Waterfall of Três
Barras, long -43.539833, lat -19.335639, 701 m a.s.l., rock-face seepages, 21.vi.2019, leg. J.B.R. Alencar” (5 exs.
INPA, in alcohol); “Santo Antônio do Itambé, Rio Guanhães, long -43.307167, lat -18.454611, 731 m a.s.l., margin
of Preto river, 21.vi.2019, leg. J.B.R. Alencar” (31 exs. INPA, in alcohol); “Santo Antônio do Itambé, Rio Preto,
long -43.320778, lat -18.461417, 702 m a.s.l., vertical surfaces with water, 30.iii.2020, leg. J.B.R. Alencar” (2 exs.
INPA, in alcohol); “Serro, Waterfall of Amaral, long -43.406944, lat -18.388528, 1043 m a.s.l., vertical surfaces
with water, 22.vi.2019, leg. J.B.R. Alencar” (17 exs. INPA, in alcohol); “Itacambira, Waterfall of Curiango, long -
43.324861, lat -17.147556, 1051 m a.s.l., vertical surfaces with water, 24.vi.2019, leg. J.B.R. Alencar” (6 exs. INPA,
in alcohol); “Mato Verde, Waterfall Maria Rosa, long -42.795444, lat -15.432167, 725 m a.s.l., vertical surfaces with
water and green algae, 25.iii.2020, leg. J.B.R. Alencar” (19 exs. INPA, in alcohol); “Serranópolis de Minas, Wa-
terfall of Serrado, long -42.843986, lat -15.677725, 720 m a.s.l., spray zones of waterfalls, 25.iii.2020, leg. J.B.R.
Alencar” (12 exs. INPA, in alcohol); “Botumirim, Waterfall Quatro Oitavas, long -43.014047, lat -16.883492, 862
m a.s.l., vertical surfaces with water, 27.iii.2020, leg. J.B.R. Alencar” (6 exs. INPA, in alcohol); “Botumirim, Water-
fall of Bananal, long -43.037042, lat -16.839917, 908 m a.s.l., vertical surfaces with water, 28.iii.2020, leg. J.B.R.
Alencar” (5 exs. INPA, in alcohol); “Serro, Waterfall of Malheiros, long -43.445917, lat -18.654139, 738 m a.s.l.,
tiver margin, 31.iii.2020, leg. J.B.R. Alencar” (9 exs. INPA, in alcohol).
Diagnosis. Large-sized species. Pronotum with rounded posterolateral margins. Elytra surface with shallowly
impressed longitudinal grooves, with sparse short setae. Elytra with sutural interval raised (Fig. 12d) and margins
explanate (Fig. 13b). Prosternum with 4–5 anteromedial spine-like setae. Abdominal ventrites dark brown, not paler
than thoracic ventrites, in strong contrast to legs and pseudoepipleura, which are from yellow to light brown.
Adult. Body length 5.0–6.0 mm (n= 10, mean= 5.72, SD= ±0.33); TL/GW 1.65±0.09 mm. General body shape
broadly oval, slightly convex.
Color. Dorsum black (Fig. 3a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending to ca. four fifths of lateral margin length. Elytra with irregular patches of bronze
or green iridescence; with row of rounded black [=without sheen] spots along suture. Each elytron with rounded
pale spot in distal quarter. Antennomeres 1–5 yellowish brown, club dark brown. Maxillary and labial palps yellow.
Ventral face of head dark brown to black. Lateral margins of prosternum; pseudoepipleura and epipleura yellowish
brown. Thorax dark brown to black ventrally. Legs light brown to yellow, except for dark brown coxae and basal
region of femora. Abdominal ventrites dark brown, with slightly lighter posterior margins on ventrites 1–4, some-
times with pale patches laterally on ventrites 2–3.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width of
one puncture (Fig. 3d). Ground punctation on labrum denser than punctation of clypeus, distance between punctures

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FIGURE 3. Oocyclus espinhacu sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d) arrow indicates the
prosternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 281
0.5–1.5× twidth of one puncture; with few distinct systematic punctures medially. Labrum sometimes bearing short
setae. Clypeus with several scattered indistinct systematic punctures laterally; sometimes bearing short setae. Frons
with irregular row of systematic punctures toward the median plane of each eye and few fine setae around ocular
suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2; apical segment longer than
penultimate segment. Labial palps about two-thirds as long as width of mentum. Mentum smooth, with scattered
coarse punctures; subquadrate, anterior margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra evenly distributed and moderately coarse (Figs. 3a, c, d).
Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; anterior and
posterior series each forming irregular field. Lateral margins of pronotum with fine setae distributed along its length,
being more densely pubescent on anterior half. Pronotal posterolateral angles rounded. Sutural interval on elytra
slightly raised along its length. Elytral interval with weak or non-existent pubescence on ground punctation (e.g.
Figs. 12a, c, d). Rows of systematic punctures on elytra present but blending with surrounding fine ground puncta-
tion and as such hardly distinguishable (e.g. Fig. 12d). Elytral surface with shallow longitudinal depressions medi-
ally in posterior half. Humeral region (in frontal view) without antero-medial elevation. Elytral margins with short
spine-like setae situated along its length and explanate on posterior half. Prosternum with clearly defined median
carina; slightly elevated anteromedially (Fig. 3e); elevated region with 4–5 spine-like setae. Elevated process of
mesoventrite wide and elongate, about twice as long as wide; slightly raised anteriorly; with 6–7 coarse spine-like
setae. Metaventrite with posteromedial oval glabrous area ca. twice as long as wide; length of glabrous area about
two-thirds length of metaventrite. Procoxae with fine short pubescence and set with coarse, short spine-like setae;
grouped on basal half. Protibiae each with 9–12 spine-like setae on dorsal face. Meso- and metafemora with scat-
tered punctures bearing short thickened, spine-like setae.
Abdomen. Ventrites covered with scattered, sparsely distributed setae of varying lengths; ventrites 1–4 with
setae shorter to subequal than longest setae around margin of metasternal glabrous area (Fig. 3b). Aedeagus: outer
margin of parameres weakly sinuous, gradually tapering to apex, curving inward; inner margin, straight, tapering
from distal half (dorsal view); median lobe shorter than parameres, without apical hook. Gonopore located at 4/5
length of median lobe. Basal piece rounded (Fig. 11b).
Etymology. The specific epithet espinhacu is derived from “Serra do Espinhaço”, the name of the Brazilian
mountain range where this species is widely distributed. To be treated as a noun in apposition.
Distribution. Brazil (Minas Gerais) (Fig. 14).
Remarks. This species shares diagnostic features with O. itapecum Clarkson & Short, 2012 and O. fryanus Bal-
four-Browne, 1939: non-pale abdominal ventrites, elytral suture raised and four prosternal spines. However, in O.
itapecum, the body shape is elongated (TL/GW =1.80), the elytra are smooth, without undulating grooves near the
suture interval, and the legs are light brown to dark brown, while in O. espinhacu sp. n. the body is less elongated
(TL/GW = 1.65), the elytra have undulating grooves near the suture interval and the legs are paler in color (light
brown to yellow). O. fryanus, for its part, has multiple pale elytral spots, a more distinctive lateral depression on
humeral region and a distinct medial indentation on the elytra easily distinguish it from O. espinhacu sp. n.
Oocyclus giganteus sp. n.
(Figs. 4a–e, 11c, 14)
Type material. Holotype (male): “BRASIL: BAHIA, Abaíra, Waterfall Guarda Mor, long -41.8606, lat -13.3127,
1272 m a.s.l., vertical surfaces with water, 13.iii.2020, leg. J.B.R. Alencar” (INPA, Coleoptera, in alcohol). Para-
types (173 exs.): BRAZIL: Bahia: Same data as holotype (94 exs. INPA; 10 exs. SEMC, in alcohol); except:
“BA-564 Piatã-Mucugê, near the road, long -41.5931, lat -13.1546, 844 m a.s.l., vertical surfaces with water and
green algae, 26.vi.2019, leg. J.B.R. Alencar” (31 exs. INPA, in alcohol); “Rio de Contas, Waterfall of Fraga, long
-41.5931, lat -13.1546, 844 m a.s.l., vertical surfaces with water, 23.iii.2020, leg. J.B.R. Alencar” (38 exs. INPA, in
alcohol).
Diagnosis. Large-sized species. Pronotum with angulate posterolateral margins. Elytra surface even, with very
fine ground punctation, with faint rows of systematic punctures (some of these punctures can be detected by pres-
ence of setae). Elytral sutural interval raised (e.g. Fig. 12d) margins explanate (e.g. Fig. 13b). Prosternum with two
anteromedial spine-like setae. Abdominal ventrites dark brown, not paler than thoracic ventrites.

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FIGURE 4. Oocyclus giganteus sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d) arrow indicates the
prosternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 283
Adult. Body length 5.7–6.3 mm (n= 10, mean= 6.02, SD= ±0.15); TL/GW 1.60±0.04 mm. General body shape
broadly oval, slightly convex.
Color. Dorsum black (Fig. 4a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending slightly beyond the half of margin length. Elytra with irregular patches of bronze
or green iridescence; with row of rounded black [=without sheen] spots along suture. Each elytron with rounded
pale spot on distal quarter. Antennomeres 1–5 yellowish brown, club dark brown. Maxillary and labial palps yellow.
Ventral face of head dark brown to black. Lateral margins of prosternum; pseudoepipleura and epipleura yellowish
brown. Thorax dark brown to black ventrally. Legs dark brown, except for light brown tarsi. Abdominal ventrites
dark brown with posterior margin of each ventrite light to brown.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 1.5–2.0× width
of one puncture (Fig. 4d). Ground punctation on labrum denser than punctation of clypeus, distance between punc-
tures 0.5–1.5× width of one puncture; with few distinct systematic punctures medially. Labrum sometimes bearing
short setae. Clypeus with several scattered indistinct systematic punctures laterally; sometimes bearing short setae.
Frons with irregular row of systematic punctures toward median plane of each eye and few fine setae around ocular
suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2; apical segment longer than
penultimate segment. Labial palps about two-thirds as long as width of mentum. Mentum smooth, with scattered
coarse punctures; subquadrate, anterior margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra evenly distributed and moderately coarse (Figs. 4a, c, d).
Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; anterior and
posterior series each forming irregular field. Lateral margins of pronotum with fine setae distributed along of its
length, being more densely pubescent on anterior half. Pronotal posterolateral angles angulate. Sutural interval on
elytra slightly raised along its length. Elytral interval with weak or non-existent pubescence in ground punctation
(e.g. Fig 12a, c, d). Rows of systematic punctures on elytra present but not larger than surrounding ground punctua-
tion and as such hardly distinguishable, blending uniformly with ground punctuation. Elytral surface with shallow
longitudinal depressions medially on posterior half. Humeral region (in frontal view) without antero-medial eleva-
tion. Elytral margins with short spine-like setae situated along its length and explanate on posterior half. Prosternum
with clearly defined median carina; slightly elevated anteromedially (Fig. 4e); elevated region with two spine-like
setae. Elevated process of mesoventrite wide and elongate, about twice as long as wide; slightly raised anteriorly;
with 6–7 coarse spine-like setae. Metaventrite with oval glabrous area posteromedially, slightly longer than wide;
length of glabrous area about half length of metaventrite. Procoxae with fine short pubescence and set with coarse,
short spine-like setae; grouped on basal. Protibiae each with 6–7 spine-like setae on dorsal face. Meso- and meta-
femora with scattered punctures bearing short thickened, spine-like setae.
Abdomen. Ventrites covered with setae of varying lengths; pubescence usually with suberect to recumbent se-
tae; longest setae shorter to subequal in length to longest setae around margin of metasternal glabrous area (Fig. 4b).
Aedeagus: outer margin of parameres weakly sinuous, gradually tapering to apex, curving inward; inner margin,
straight, tapering from the distal half (dorsal view); median lobe subequal in length to the parameres, without hook
in apex. Gonopore located at four-fifths the length of median lobe. Basal piece constricted (Fig. 11c).
Etymology. The specific epithet giganteus derived from giga- (G.), meaning giant, refers to the large size of the
body. To be treated as a noun in apposition.
Distribution. Brazil (Bahia) (Fig. 14).
Remarks. This species shares several diagnostic features with O. flexus Clarkson & Short, 2012: non-pale ab-
dominal ventrites, elytral suture raised, and the presence of two prosternal spines. However, in O. flexus the postero-
lateral margins of the pronotum are broadly rounded and shorter body length (4.4–5.2 mm), while the posterolateral
margins of the pronotum are angulate and the body size varies from 5.7–6.3 mm in O. giganteus sp. n.
Oocyclus humboldti sp. n.
(Figs. 5a–e, 11d, 14)
Type material. Holotype (male): “BRASIL: MINAS GERAIS, Parque Estadual Serra do Cabral, Waterfall of
Demir, long -44.211975 lat -17.920439, 833 m a.s.l., rock-face seepages, 14.iv.2019, leg. J.B.R. Alencar” (INPA,
in alcohol). Paratypes (266 exs.): BRAZIL: Minas Gerais: Same data as holotype (20 exs. INPA; 10 exs. SEMC,
in alcohol); except: “Waterfall of Boqueirão, long -44.178528, lat -17.758333, 680 m a.s.l., rock-face seepages,

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13.iv.2019, leg. J.B.R. Alencar” (32 exs. INPA, in alcohol); “Waterfall of Fervedouro, long -44.247978, lat -17.917764,
1071 m a.s.l., rock-face seepages, 14.iv.2019, leg. J.B.R. Alencar” (1 ex. INPA, in alcohol); “Curimataí, Waterfall of
Simão, long -43.955333, lat -17.896139, 650 m a.s.l., rock-face seepages, 16.iv.2019, leg. J.B.R. Alencar” (28 exs.
INPA, in alcohol); “PARNA Sempre Vivas, Waterfall of Felipes, long -43.703639, lat -17.907472, 1090 m a.s.l.,
rock-face seepages, 24.iv.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); “Parque Estadual Grão Mogol, Wa-
terfall of Almas, long -42.931194, lat -16.618139, 691 m a.s.l., rock-face seepages, 29.iv.2019, leg. J.B.R. Alencar”
(2 exs. INPA, in alcohol); “Parque Estadual Grão Mogol, Stream of the Dé, long -42.963833, lat -16.592361, 746
m a.s.l., rock-face seepages, 29.iv.2019, leg. J.B.R. Alencar” (10 exs. INPA, in alcohol); “Parque Estadual Grão
Mogol, Waterfall of Almas, long -42.870111, lat -16.511139, 624 m a.s.l., rock-face seepages, 30.iv.2019, leg.
J.B.R. Alencar” (27 exs. INPA, in alcohol); “Lassance, Waterfall of Palmeiras, long -44.504167, lat -17.834333,
520 m a.s.l., vertical surfaces with water, 1.v.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); “PARNA Serra
do Cipó, Waterfall Capão dos Palmitos, long -43.609556, lat -19.377472, 830 m a.s.l., rock-face seepage, 8.vi.2019,
leg. J.B.R. Alencar” (9 exs. INPA, in alcohol); “Waterfall Taioba, long -43.571806 lat -19.391806, 863 m a.s.l.,
vertical surfaces with water, 9.vi.2019, leg. J.B.R. Alencar” (7 exs. INPA, in alcohol); “Canyon of the Bandeirinhas,
long -43.562722, lat -19.423917, 880 m a.s.l., seepage habitat, 11.vi.2019, leg. J.B.R. Alencar” (8 exs. INPA, in
alcohol); “Itabirito, Corrego Prox a Fazenda Velha, long -43.809139, lat -20.299111, 862 m a.s.l., rock-face seep-
ages, 20.vi.2019, leg. J.B.R. Alencar” (82 exs. INPA, in alcohol); “Serro, Waterfall of Amaral, long -43.406944, lat
-18.388528, 1043 m a.s.l., vertical surfaces with water, 22.vi.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol);
“Gameleiras, Waterfall of Andorinhas, long -43.079419, lat -14.981272, 931 m a.s.l., vertical surfaces with water
and green algae, 24.iii.2019, leg. J.B.R. Alencar” (5 exs. INPA, in alcohol); “Mato Verde, Waterfall Maria Rosa,
long -42.795444, lat -15.432167, 725 m a.s.l., vertical surfaces with water and green algae, 25.iii.2020, leg. J.B.R.
Alencar” (3 exs. INPA, in alcohol); Bahia: “BAHIA, BA-564 Piatã-Mucugê, near the road, long -41.593139, lat
-13.154611, 844 m a.s.l., vertical surfaces with water and green algae, 26.vi.2019, leg. J.B.R. Alencar” (16 exs.
INPA, in alcohol).
Diagnosis. Small to medium-sized species. Pronotum with rounded posterolateral margins. Elytra surface even,
with rows of fine systematic punctures bearing short setae, interrupted in some regions along their length; lateral
rows very indistinct, blending with surrounding ground punctation. Elytral sutural interval not raised (Figs. 12a–c).
Prosternum with two anteromedial spine-like setae. Abdominal ventrites pale, all ventrites usually with distinct
medial dark macula (varying in width).
Adult. Body length 3.5–4.2 mm (n= 10, mean= 3.91, SD= ±0.24); TL/GW 1.65±0.10 mm. General body shape
broadly oval, strongly convex.
Color. Dorsum black (Fig. 5a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with wide pale strip, extending to ca. 4/5 of lateral margin length. Elytra with irregular patches of bronze
or green iridescence; without row of rounded black [=without sheen] spots along suture. Each elytron with rounded
pale spot on distal quarter. Antennae with antennomeres 1–5 and 3-segmented club yellowish brown. Maxillary and
labial palps yellow. Ventral face of head dark brown to black. Lateral margins of prosternum black to dark brown;
pseudoepipleura and epipleura yellowish brown. Thorax, ventrally brown to black, with lighter posterior margins in
metaventrite, sometimes extending laterally along entire length of anepisternum. Legs light brown, except for dark
brown coxae and basal region of femora. Abdominal ventrites brownish yellow, usually with distinct medial dark
macula, sometimes completely covering ventrite.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width
of one puncture (Fig. 5d). Ground punctation on labrum denser than punctation of clypeus, distance between punc-
tures 0.5–1.5× width of one puncture; with few distinct systematic punctures medially. Labrum sometimes bearing
short setae. Clypeus with several scattered indistinct systematic punctures laterally; and sometimes bearing short
setae. Frons with irregular row of systematic punctures toward the median plane of each eye and few fine setae
around ocular suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2; apical seg-
ment longer than penultimate segment. Labial palps about two-thirds as long as width of mentum. Mentum smooth,
with scattered coarse punctures; subquadrate, anterior margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra evenly distributed and moderately coarse (Figs. 5a, c, d).
Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; anterior and
posterior series each forming an irregular field. Lateral margins of pronotum with fine setae distributed along its
length, being more densely pubescent on anterior half. Pronotal posterolateral angles rounded. Sutural interval on

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 285
FIGURE 5. Oocyclus humboldti sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d) arrow indicates the
prosternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

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elytra not raised. Elytral interval composed of short setae forming inconspicuous rows. Five rows of systematic
punctures: rows 1 and 2 each represented by regular series of punctures; punctures not larger that surrounding punc-
tuation and at about the same spacing. Rows 3–5 with punctures not larger than surrounding ground punctuation
and as such hardly distinguishable. Elytral surface without shallow longitudinal depressions medially on posterior
half. Humeral region (in frontal view) without anteromedial elevation. Elytral margins with short spine-like setae
situated along its length. Prosternum with clearly defined median carina; slightly elevated anteromedially (Fig. 5e);
elevated region with two spine-like setae. Elevated process of mesoventrite wide and elongate, about twice as long
as wide; slightly raised anteriorly; with 5–6 coarse spine-like setae. Metaventrite with oval glabrous area posterome-
dially, slightly longer than wide; length of glabrous area about two-thirds of length of metaventrite. Procoxae with
fine short pubescence and set with coarse, short spine-like setae; grouped on basal half. Protibiae each with eight
spine-like setae on dorsal face. Meso- and metafemora with scattered punctures bearing short thickened, spine-like
setae.
Abdomen. Ventrites covered with scattered, long setae; ventrites 1–4 with scattered, long setae, distinctly
longer than longest setae on metaventrite, ventrite 5 more densely pubescent (Fig. 5b). Aedeagus: outer margin of
parameres weakly sinuous, gradually tapering to apex, straight; inner margin, straight, gradually tapering towards
apex (dorsal view); median lobe shorter than parameres, without apical hook. Gonopore located at four-fifths of
median lobe. Basal piece tapered (Fig. 11d).
Etymology. The specific epithet humboldti is in honor to Friedrich Wilhelm Heinrich Alexander von Humboldt,
he was one of the pioneers to propose relationships between South American mountain environments and biodiver-
sity. To be treated as a noun in apposition.
Distribution. Brazil (Minas Gerais) (Fig. 14).
Remarks. This species was found in rock-face seepages along streams, as well as in marginal areas that simu-
late infiltrations due to low flow. This species shares distinguishable diagnostic features with O. rotundus Clarkson
& Short, 2012 such as pale abdominal ventrites (in most specimens), absence of black circular spots along the elytral
suture and a nearly circular, strongly convex body. However, in O. rotundus the median lobe is distinctly shorter
than the parameres and it has a tapered basal piece in contrast to O. humboldti sp. n. which has short setae on the
elytral surface and the median lobe is slightly shorter than the length of the parameres, and the basal piece is rounded
(Fig. 11d).
Oocyclus lacia sp. n.
(Figs. 6a–e, 11e, 14)
Type material. Holotype (male): “BRASIL: MINAS GERAIS, Serro, Waterfall of Amaral, long -43.4069, lat
-18.3885, 1043 m a.s.l., vertical surfaces with water, 22.vi.2019, leg. J.B.R. Alencar” (INPA, Coleoptera, in alco-
hol).
Diagnosis. Large-sized species. Pronotum with rounded posterolateral margins. Elytra surface with shallowly
impressed longitudinal grooves and sparse short setae. Elytral sutural interval raised (e.g. Fig. 12d). Prosternum
with six anteromedial spine-like setae. Abdominal ventrites dark brown, not paler than thoracic ventrites.
Adult. Body length 4.9 mm (n= 1); TL/GW 1.73 mm. General body shape broadly oval, slightly convex.
Color. Dorsum black (Fig. 6a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending to ca. 4/5 of lateral margin length. Elytra with faint, often indistinct yellowish
or bronze maculae, especially near the suture; with row of rounded black [=without sheen] spots along suture. Each
elytron with two to three small circular pale spots: two anterior pale spot very close together in distal third, about
twice as far from suture than posterior spot; posterior spot situated in distal quarter. Antennomeres 1–5 yellowish
brown, club dark brown. Maxillary and labial palps yellow. Ventral face of head dark brown to black. Lateral mar-
gins of prosternum and pseudoepipleura yellowish brown; and epipleura dark brown to black. Thorax dark brown
to black ventrally. Legs brown to dark brown, except for light brown tarsi. Abdominal ventrites dark brown, with
slightly lighter posterior margins in ventrites 1–4, sometimes with pale patches laterally in ventrites 2–3.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width
of one puncture (Fig. 6d). Ground punctation on labrum denser than punctation of clypeus, distance between punc-
tures 0.5–1.5× width of one puncture; with few distinct systematic punctures medially. Labrum bearing short setae.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 287
FIGURE 6. Oocyclus lacia sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d) arrow indicates the
prosternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

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Clypeus with several scattered indistinct systematic punctures laterally; and sometimes bearing short setae. Frons
with irregular row of systematic punctures toward the median plane of each eye and few fine setae around ocular
suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2; apical segment longer than
penultimate segment. Labial palps about two-thirds as long as width of mentum. Mentum smooth, with scattered
coarse punctures; subquadrate, anterior margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra evenly distributed and moderately coarse (Figs. 6a, c, d).
Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; anterior and
posterior series each forming irregular field. Lateral margins of pronotum with fine setae distributed along of its
length, being more densely pubescent on anterior half. Pronotal posterolateral angles rounded. Sutural interval on
elytra slightly raised along its length. Elytral interval with weak or non-existent pubescence in ground punctation
(e.g. Figs. 12a, c, d). Rows of systematic punctures on elytra present but blending with surrounding ground puncta-
tion and as such hardly distinguishable. Elytral surface without shallow longitudinal depressions medially on pos-
terior half. Humeral region (in frontal view) without anteromedial elevation. Elytral margins with short spine-like
setae situated along its length. Prosternum with clearly defined median carina; strongly elevated anteromedially
(Fig. 6e); elevated region with six spine-like setae. Elevated process of mesoventrite wide and elongate, about three
times as long as wide; slightly raised anteriorly; with five coarse spine-like setae. Metaventrite with posteromedial
oval glabrous area ca. twice as long as wide; length of glabrous area about three-quarters length of metaventrite.
Procoxae with fine short pubescence and set with coarse, short spine-like setae; grouped on basal half. Protibiae
each with 7–9 spine-like setae on dorsal face. Meso- and metafemora with scattered punctures bearing short thick-
ened, spine-like setae.
Abdomen. Ventrites covered with setae of varying lengths; ventrites 1–4 rather sparsely pubescent with scat-
tered, long setae, distinctly longer than longest setae on metaventrite, ventrite 5 more densely pubescent (Fig. 6b).
Aedeagus: outer margin of parameres weakly sinuous, gradually tapering to apex, not curving inward; inner margin,
straight, tapering from distal half (dorsal view); median lobe shorter than parameres, without apical hook. Gonopore
located at four-fifths of median lobe. Basal piece tapered (Fig. 11e).
Etymology. The specific epithet lacia derived from the acronym of the Laboratório de Citotaxonomia e Inse-
tos Aquáticos, within the Instituto Nacional de Pesquisas da Amazônia, in Brazil. It is a tribute to all the support
received for the development of this work. To be treated as a noun in apposition.
Distribution. Brazil (Minas Gerais) (Fig. 14).
Remarks. This species shares diagnostics feature with O. fryanus, such as non-pale abdominal ventrites, large
size (>5.0 mm), and six prosternal spines. However, O. fryanus has a lateral indentation on the elytra, the shape
of the body is very elongated (TL/GW = 1.85) and does not have elytra grooves, in O. lacia sp. n. a lateral elytral
indentation is absent, body is more oval (TL/GW =1.73) and elytra have grooves.
Oocyclus ovalis sp. n.
(Figs. 7a–e, 11f, 12c, 13a, 14)
Type material. Holotype (male): “BRASIL: MINAS GERAIS, Serro, Waterfall of Malheiros, long -43.4459, lat
-18.6541, 738 m a.s.l., rock-face seepages, 31.iii.2020, leg. J.B.R. Alencar” (INPA, Coleoptera, in alcohol). Para-
types (14 exs.): BRAZIL: Minas Gerais: Same data as holotype (10 exs. INPA; 4 exs. SEMC, in alcohol).
Diagnosis. Medium-sized species. Pronotum with rounded posterolateral margins. Elytra surface even, with
rows of fine systematic punctures bearing short setae, interrupted in some regions along their length; lateral rows
very indistinct, blending with surrounding ground punctation. Elytral sutural interval not raised (Fig. 12c). Pro-
sternum with two or four anteromedial spine-like setae. Abdominal ventrites brown to dark brown, not paler than
thoracic ventrites.
Adult. Body length 4.0–4.4 mm (n= 10, mean= 4.21, SD= ±0.21); TL/GW 1.55 ±0.08 mm. General body shape
broadly oval, strongly convex.
Color. Dorsum black (Fig. 7a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending to ca. 4/5 of lateral margin length. Elytra with irregular patches of bronze or
green iridescence; without row of rounded black [=without sheen] spots along suture. Each elytron with one rounded
pale spot on distal quarter. Antennomeres 1–5 yellowish brown, club dark brown. Maxillary and labial palps yellow.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 289
FIGURE 7. Oocyclus ovalis sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d) arrow indicates the
prosternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

ALENCAR ET AL.
290 · Zootaxa 5087 (2) © 2022 Magnolia Press
Ventral face of head dark brown to black. Lateral margins of prosternum; pseudoepipleura and epipleura yellowish
brown. Thorax, ventrally brown to black. Legs brown with bronze or green iridescence, except for light brown tarsi.
Abdominal ventrites brown to dark brown.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0×width
of one puncture (Fig. 7d). Ground punctation on labrum denser than punctation of clypeus, distance between punc-
tures 0.5–1.5×width of one puncture; with few distinct systematic punctures medially. Labrum sometimes bearing
short setae. Clypeus with few distinct systematic punctures along anterolateral margins, larger than surrounding
punctation and sometimes bearing short setae. Frons with irregular row of systematic punctures toward the median
plane of each eye and few fine setae around ocular suture. Maxillary palps subequal in length to width of labrum;
segment 3 shorter than segment 2; apical segment longer than penultimate segment. Labial palps about two-thirds
as long as width of mentum. Mentum smooth, with scattered coarse punctures; subquadrate, anterior margin slightly
convex and depressed.
Thorax. Ground punctation on pronotum and elytra evenly distributed and moderately coarse (Figs. 7a, c, d).
Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; anterior and
posterior series each forming an irregular field. Lateral margins of pronotum with fine setae distributed along of
its length, being more densely pubescent on anterior half. Pronotal posterolateral angles broadly rounded. Sutural
interval on elytra not raised (Fig. 12c). Elytral interval with weak or non-existent pubescence in ground punctation.
Five rows of systematic punctures: rows 1 and 2 each bearing one small recumbent setae; punctures not larger than
surrounding punctuation and at about the same spacing. Rows 3–5 each represented by punctures not larger than
surrounding ground punctuation; bearing short setae and as such hardly distinguishable (Fig. 12c). Elytral surface
without shallow longitudinal depressions medially on posterior half (Fig. 13a). Humeral region (in frontal view)
without anteromedial elevation. Elytral margins with short spine-like setae situated along their length. Prosternum
with clearly defined median carina, slightly elevated anteromedially (Fig. 7e); elevated region with two or four
spine-like setae. Elevated process of mesoventrite wide and elongate, about twice as long as wide; slightly raised
anteriorly; with 4–6 coarse spine-like setae. Metaventrite with posteromedial oval glabrous area ca. twice as long as
wide; length of glabrous area about two-thirds length of metaventrite. Procoxae with fine short pubescence and set
with coarse, short spine-like setae; grouped on basal half. Meso- and metafemora with scattered punctures bearing
short thickened, spine-like setae.
Abdomen. Ventrites covered with scattered, sparsely distributed setae of varying lengths; ventrites 1–4 with
scattered, long setae, distinctly longer than longest setae on metaventrite, ventrite 5 more densely pubescent (Fig.
7b). Aedeagus: outer margin of parameres sinuous, gradually tapering to apex, not curving inward; inner margin,
straight, tapering from distal half (dorsal view); median lobe shorter than parameres, without apical hook. Gonopore
located at four-fifths of median lobe. Basal piece tapered (Fig. 11f).
Etymology. The specific epithet ovalis (L.), refers to the "egg-shaped" body. To be treated as a noun in apposi-
tion.
Distribution. Brazil (Minas Gerais) (Fig. 14).
Remarks. This species shares distinguishable diagnostic features with O. caparao and O. ecolab sp. n.: non-
pale abdominal ventrites, elytral suture not raised, elytra surface with rows of systematic punctures bearing short
setae. However, O. caparao differs from O. ovalis sp. n. by elytral surface with very shallowly impressed longitu-
dinal grooves near the suture and by the prosternum set with six spine-like setae, in most specimens. O. ecolab sp.
n. differs from O. ovalis sp. n. by a row of rounded black [=without sheen] spots along elytral suture and two small
circular pale spots on each elytron.
Oocyclus sulcatus sp. n.
(Figs. 8a–d, 11g, 12d, 13b, 14)
Type material. Holotype (male): “BRASIL: BAHIA, PARNA Chapada Diamantina, Waterfall da Fumaça, long
-41.456278, lat -12.600333, 1286 m a.s.l., vertical surfaces with water, 19.iii.2020, leg. J.B.R. Alencar” (INPA, in
alcohol). Paratypes (41 exs.): BRAIL: Bahia: Same data as holotype (4 exs. INPA, in alcohol); except “Waterfall
of Mosquito, long -41.3705 lat -12.3706, 517 m a.s.l., vertical surfaces with water, 29.vi.2019, leg. J.B.R. Alencar”
(3 exs. INPA, in alcohol); “Waterfall da Matinha, long -41.3358 lat -13.0765 1021 m a.s.l., vertical surfaces with wa-
ter, 21.iii.2020, leg. J.B.R. Alencar” (21 exs. INPA; 10 exs. SEMC, in alcohol); “Palmeiras, Waterfall of Riachinho,

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 291
long -41.5157, lat -12.5721, 935 m a.s.l., vertical surfaces with water, 18.iii.2020, leg. J.B.R. Alencar” (1 ex. INPA,
in alcohol).
Diagnosis. Large-sized species. Pronotum with rounded posterolateral margins. Elytra surface with impressed
longitudinal grooves and shallow longitudinal depressions medially in posterior half, rows of systematic punctures
present, but blending with surrounding coarse ground punctation and as such hardly distinguishable (Fig. 12d). Ely-
tral sutural interval raised (Fig. 12d) and margins explanate (Fig. 13b). Prosternum with two anteromedial spine-like
setae. Abdominal ventrites dark brown, not paler than thoracic ventrites.
Adult. Body length 5.2–6.2 mm (n= 10, mean= 5.88, SD= ±0.31); TL/GW 1.60±0.08 mm. General body shape
broadly oval, strongly convex.
Color. Dorsum black (Fig. 8a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending to ca. 4/5 of lateral margin length. Elytra with faint, often indistinct yellowish
or bronze maculae, especially near suture; with row of rounded black [=without sheen] spots along suture. Each
elytron with one rounded pale spot on distal quarter. Antennomeres 1–5 yellowish brown, club dark brown. Maxil-
lary and labial palps yellow. Ventral face of head dark brown to black. Lateral margins of prosternum and pseudo-
epipleura yellowish brown; and epipleura brown. Thorax dark brown to black ventrally. Legs dark brown, except for
light brown tarsi. Abdominal ventrites dark brown with posterior margin of each ventrite light to brown.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width
of one puncture (Fig. 8d). Ground punctation on labrum denser than punctation of clypeus, distance between punc-
tures 0.5–1.5× width of one puncture; with few distinct systematic punctures medially. Labrum sometimes bearing
short setae. Clypeus with several scattered indistinct systematic punctures laterally; and sometimes bearing short
setae. Frons with irregular row of systematic punctures toward the median plane of each eye and few fine setae
around ocular suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2; apical seg-
ment longer than penultimate segment. Labial palps about two-thirds as long as width of mentum. Mentum smooth,
with scattered coarse punctures; subquadrate, anterior margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra unevenly distributed and moderately coarse; elytra with
distinctly larger punctures and with shallowly impressed longitudinal grooves (Figs. 8a, c, d). Pronotal systematic
punctures similar in size to surrounding ground punctures; anterior and posterior series each forming an irregular
field. Lateral margins of pronotum with fine setae distributed along its length, more densely pubescent on anterior
half. Pronotal posterolateral angles rounded. Sutural interval on elytra (Fig. 12d) slightly raised. Elytral interval with
weak or non-existent pubescence in ground punctation. Rows of systematic punctures on elytra present but blend-
ing with surrounding coarse ground punctation and as such hardly distinguishable (Fig. 12d). Elytral surface with
shallow longitudinal depressions medially on posterior half (Fig. 13b). Humeral region (in frontal view) distinctly
elevated anteromedially. Elytra margins with short spine-like setae spaced along its length and explanate on poste-
rior half. Prosternum with clearly defined median carina; slightly elevated anteromedially (Fig. 8e); elevated region
with two spine-like setae. Elevated process of mesoventrite wide and elongate, about twice as long as wide; slightly
raised anteriorly; with six coarse spine-like setae. Metaventrite with posteromedial oval glabrous area ca. twice as
long as wide; length of glabrous area about three-quarters of metaventrite. Procoxae with fine short pubescence and
set with coarse, short spine-like setae; grouped on basal half. Protibiae each with 7–9 spine-like setae on dorsal face.
Meso- and metafemora with scattered punctures bearing short thickened, spine-like setae.
Abdomen. Ventrites covered with setae of varying lengths; ventrites 1–4 with scattered long erect setae, dis-
tinctly longer than longest setae on metaventrite (Fig. 8b). Aedeagus: outer margin of parameres weakly sinuous,
gradually tapering to apex, curving inward; inner margin, straight, tapering from distal half (dorsal view); median
lobe subequal in length to parameres, without apical hook. Basal piece rounded (Fig. 11g).
Etymology. The specific epithet sulcatus (L.), refers to the grooved elytra. To be treated as a noun in apposi-
tion.
Distribution. Brazil (Bahia) (Fig. 14).
Remarks. This species shares some diagnostic features with O. iguazu (Oliva, 1996): such as non-pale ab-
dominal ventrites, large-size (>5.0 mm) and two prosternal spines. However, O. sulcatus sp. n. can be easily distin-
guished by its impressed longitudinal grooves and shallow longitudinal depressions medially on the posterior part
of elytra (Fig. 13b). In some specimens, the visualization of the diagnostic spots and green or bronze sheen (irides-
cence) depends on the view and lighting, sometimes they are not captured in the photographs, visible by moving the
specimen or by changing the lighting system of the photographic equipment.

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FIGURE 8. Oocyclus sulcatus sp. n., dorsal (a), ventral (b), lateral habitus (c); antero-dorsal view (d); arrow indicates the pros-
ternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 293
Oocyclus thrixdiastematus sp. n.
(Figs. 8a–d, 11h, 12b, 14)
Type material. Holotype (male): “BRASIL: MINAS GERAIS, PARNA Serra do Cipó, Waterfall Capão dos
Palmitos, long -43.6096, lat -19.3775, 830 m a.s.l., rock-face seepage, 8.vi.2019, leg. J.B.R. Alencar” (INPA, Co-
leoptera, in alcohol). Paratypes (30 exs.): BRAZIL: Minas Gerais: Same data as holotype (5 exs. INPA, in alco-
hol); except: “Waterfall of Andorinhas, long -43.4915, lat -19.2376, 577 m a.s.l., rock-face seepages, 10.vi.2019,
leg. J.B.R. Alencar” (1 ex. INPA, in alcohol);”Canyon of the Bandeirinhas, long -43.5627, lat -19.4239, 880 m
a.s.l., seepage habitat, 11.vi.2019, leg. J.B.R. Alencar” (3 exs. INPA, in alcohol); “PARNA Serra do Gandarela,
Waterfall of Mingu, long -43.7596, lat -20.0622, 1006 m a.s.l., rock-face seepages, 15.vi.2019, leg. J.B.R. Alencar”
(2 exs. INPA, in alcohol); “Parque Estadual Serra do Cabral, Waterfall of Demir, long -44.212 lat -17.9204, 833
m a.s.l., rock-face seepages, 14.iv.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); “Diamantina, Waterfall of
Andorinhas, long -43.5949 lat -18.2309, 1168 m a.s.l., 11.iv.2019, leg. J.B.R. Alencar” (1 ex. INPA, in alcohol);
“Lassance, Waterfall of Palmeiras, long -44.5042, lat -17.8343, 520 m a.s.l., vertical surfaces with water, 1.v.2019,
leg. J.B.R. Alencar” (8 exs. INPA, in alcohol); Goias: “Alto Paraíso de Goiás, Waterfall da muralha, long -47.7507,
lat -14.2774, 957 m a.s.l., 2.VII.2019, leg. J.B.R. Alencar” (4 exs. INPA; 4 exs. SEMC, in alcohol).
Diagnosis. Medium-sized species. Pronotum with rounded posterolateral margins. Elytra surface even, with
rows of systematic punctures present, but merging with ground punctation, both (ground punctures and systematic
punctures) bearing fine setae, appearing pubescent in dorsal view and each elytron with two small pale circular
spots. Elytra sutural interval not raised (Fig. 12b). Prosternum with two anteromedial spine-like setae. Abdominal
ventrites dark brown, not paler than thoracic ventrites.
Adult. Body length 4.0–4.7 mm (n= 10, mean= 4.55, SD= ±0.23); TL/GW 1.65±0.09 mm. General body shape
broadly oval, slightly convex.
Color. Dorsum black (Fig. 9a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending to ca. 2/3 of lateral margin length. Elytra with irregular patches of bronze or
green iridescence; with row of rounded black [=without sheen] spots along suture. Each elytron with two small
circular pale spots: anterior spot on distal third, about twice as far from suture than posterior spot; posterior spot
situated on distal quarter. Antennae yellowish brown. Maxillary palps and labial palps yellow. Ventral face of head
dark brown to black. Lateral margins of prosternum; pseudoepipleura and epipleura yellowish brown. Thorax dark
brown to black ventrally. Legs light brown to yellow, except for dark brown coxae and basal region of femora. Ab-
dominal ventrites dark brown, with slightly lighter posterior margins on ventrites1–4, sometimes with pale patches
laterally on ventrites 2–3.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width
of one puncture (Fig. 9d). Ground punctation on labrum denser than punctation of clypeus, distance between punc-
tures 0.5–1.5× width of one puncture; with few distinct systematic punctures medially. Labrum sometimes bearing
short setae. Clypeus with several scattered indistinct systematic punctures laterally; and sometimes bearing short
setae. Frons with irregular row of systematic punctures toward the median plane of each eye and few fine setae
around ocular suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2; apical seg-
ment longer than penultimate segment. Labial palps about two-thirds as long as width of mentum. Mentum smooth,
with scattered coarse punctures; subquadrate, anterior margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra evenly distributed and moderately coarse (Figs. 9a, c, d).
Pronotal systematic punctures with short fine setae, at least 2× size of surrounding ground punctures; the anterior
and posterior series each forming an irregular field. Lateral margins of pronotum with fine setae distributed along its
length, being more densely pubescent in the anterior half. Pronotal posterolateral angles rounded. Sutural interval on
elytra not raised. Elytral interval with prominent pubescence on ground punctation (Fig. 12b). Rows of systematic
punctures on elytra present but not larger than surrounding ground punctuation and as such hardly distinguishable,
blending uniformly with ground punctuation. Elytral surface without shallow longitudinal depressions medially on
posterior half. Humeral region (in frontal view) without anteromedial elevation. Elytral margins with short spine-
like setae situated along their length. Prosternum with a clearly defined median carina; slightly elevated anteromedi-
ally (Fig. 9e); elevated region with two spine-like setae. Elevated process of mesoventrite wide and elongate, about
twice as long as wide; slightly raised anteriorly; with 5–7 coarse spine-like setae. Metaventrite with posteromedial
oval glabrous area ca. twice as long as wide; length of glabrous area about three-quarters length of metaventrite.

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FIGURE 9. Oocyclus thrixdiastematus sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d) arrow indi-
cates the prosternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 295
Procoxae with fine short pubescence and set with coarse, short spine-like setae; grouped on basal half. Protibiae
each with 6–7 spine-like setae on dorsal face. Meso- and metafemora with scattered punctures bearing short thick-
ened, spine-like setae.
Abdomen. Ventrites covered with scattered, sparsely distributed setae of varying lengths; ventrites 1–4 with
scattered, long setae, distinctly longer than longest setae on metaventrite, ventrite 5 more densely pubescent (Fig.
9b). Aedeagus: outer margin of parameres weakly sinuous, gradually tapering to apex, curving inward; inner mar-
gin, straight, tapering from distal half (dorsal view); median lobe shorter than parameres, without apical hook.
Gonopore located at medial half of median lobe. Basal piece tapered (Fig. 11h).
Etymology. The specific epithet thrixdiastematus is a combination of the adjective thrix (G.), meaning “hairy”
referring to the prominent pubescence on elytral intervals and the noun diastema (G.), meaning “space” or “inter-
val” which refers to the location of pubescence on elytra. To be treated as a noun in apposition.
Distribution. Brazil (Bahia, Minas Gerais and Goias) (Fig. 14).
Remarks. This species shares with O. ecolab sp. n. the non-pale abdominal ventrites, elytral surface with rows
of systematic punctures bearing short setae, each elytron with two small circular spots and two prosternal spines.
However, both species can be distinguished by the following characters: O. ecolab sp. n. has the elytral interval with
weak or non-existent pubescence in ground punctation; aedeagus with gonopore located at 4/5 the length on median
lobe and the basal piece is rounded and short, while O. thrixdiastematus sp. n. has the elytral interval with dense
pubescence, aedeagus with gonopore located at half on median lobe and the basal piece is tapered. The aedeagus
of O. thrixdiastematus sp. n. is similar to that of O. pilosus Jordão, Clarkon & Ferreira-Jr, 2018 and co-occurs in at
least some localities the same locality, but O. pilosus is easily distinguishable by the absence of the two spines-like
setae in prosternum.
Oocyclus thysanus sp. n.
(Figs. 10a–e, 11i, 12a, 14)
Type material. Holotype (male): “BRASIL: MINAS GERAIS, PARNA Serra do Cipó, Waterfall da Farofa, long
-43.5761, lat -19.3794, 866 m a.s.l., vertical surfaces with water, 8.vi.2019, leg. J.B.R. Alencar” (INPA, Coleoptera,
in alcohol). Paratypes (10 exs.): BRAZIL: Minas Gerais: Same data as holotype (2 exs. INPA, in alcohol); except:
“PARNA Serra do Gandarela, Waterfall of Mingu, long -43.7596, lat -20.0622, 1006 m a.s.l., rock-face seepages,
15.vi.2019, leg. J.B.R. Alencar” (2 exs. INPA; 1 ex. SEMC, in alcohol); “Parque Estadual Rola-Moça, Waterfall
of Sazona, long-43.9899, lat -20.0966, 1335 m a.s.l., rock-face seepages, 18.vi.2019, leg. J.B.R. Alencar” (2 exs.
INPA; 1 ex. SEMC, in alcohol). Goias: “GOIÁS: Alto Paraíso de Goiás, Waterfall of Muralha, long -47.7507, lat
-14.2774, 957 m a.s.l., 2.VII.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol).
Diagnosis. Large-sized species. Pronotum with angulate posterolateral margins. Elytral surface even, with rows
of fine systematic punctures, row 1 very distinctly impressed and bearing erect setae, interrupted in some regions
along their length; lateral rows very indistinct, blending with surrounding ground punctation. Elytral sutural interval
not raised (Fig. 12a). Prosternum with two anteromedial spine-like setae. Abdominal ventrites dark brown, not paler
than thoracic ventrites.
Adult. Body length 4.7–5.4 mm (n= 10, mean= 5.11, SD= ±0.22); TL/GW 1.60±0.07 mm. General body shape
broadly oval, slightly convex.
Color. Dorsum black (Fig. 10a), covered with dense, irregular green or bronze sheen. Anterolateral margins of
pronotum with pale strip, extending to ca. 4/5 of lateral margin length. Elytra with irregular patches of bronze or
green iridescence; without row of rounded black [=without sheen] spots along suture. Each elytron with rounded
pale spot on distal quarter. Antennomeres 1–5 yellowish brown, club dark brown. Maxillary and labial palps yellow.
Ventral face of head dark brown to black. Lateral margins of prosternum black to dark brown; pseudoepipleura yel-
lowish brown; epipleura brown. Thorax, ventrally brown to black. Legs brown to dark brown, except for the light
brown tarsi. Abdominal ventrites dark brown with posterior margin of each ventrite light to brown.
Head. Ground punctation on clypeus and frons moderately coarse, distance between punctures 2.0–3.0× width
of one puncture (Fig. 10d). Ground punctation on labrum denser than punctation of clypeus, distance between punc-
tures 0.5–1.5× width of one puncture; with few distinct systematic punctures medially. Labrum sometimes bearing
short setae. Clypeus with several scattered indistinct systematic punctures laterally; sometimes bearing short setae.

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FIGURE 10. Oocyclus thysanus sp. n., dorsal (a), ventral (b) and, lateral habitus (c), antero-dorsal view (d), arrow indicates
prosternal carina (e) (paratype). Scale bar: a, b and c = 1.0 mm; d = 0.5 mm and e = 0.2 mm.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 297
Frons with irregular row of systematic punctures toward the median plane of each eye and few fine setae around
ocular suture. Maxillary palps shorter than width of labrum; segment 3 shorter than segment 2. Labial palps about
two-thirds as long as width of mentum. Mentum smooth, with scattered coarse punctures; subquadrate, anterior
margin slightly convex and depressed.
Thorax. Ground punctation on pronotum and elytra unevenly distributed and moderately coarse; elytra punc-
tures slightly larger (Figs. 10a, c, d). Pronotal systematic punctures with short fine setae, at least 2× size of surround-
ing ground punctures; the anterior and posterior series each forming one irregular field. Lateral margins of pronotum
with fine setae distributed along its length, more densely pubescent on anterior half. Pronotal posterolateral angles
angulate. Sutural interval on elytra (Fig. 12a) not raised. Elytral interval with weak or non-existent pubescence in
ground punctation (Fig 12a). Five rows of systematic punctures: row 1 represented as nearly continuous row of
densely distributed, small punctures bearing long, erect setae, (Fig. 12a). Rows 2–5 each represented by punctures
only slightly larger than surrounding ground punctuation and hardly distinguishable, some set with short setae. Ely-
tral surface with shallow longitudinal depressions medially on posterior half. Humeral region (in frontal view) with-
out anteromedial elevation. Elytral margins with short spine-like setae situated along their length and explanate on
posterior half. Prosternum with clearly defined median carina; slightly elevated anteromedially (Fig. 2e); elevated
region with two spine-like setae. Elevated process of mesoventrite wide and elongate, about twice as long as wide;
slightly raised anteriorly; with 5–6 coarse spine-like setae. Metaventrite with oval glabrous area posteromedially,
slightly longer than wide; length of glabrous area about one-third length of metaventrite. Procoxae with fine short
pubescence and set with coarse, short spine-like setae; grouped on basal half. Protibiae each with eight spine-like
setae on dorsal face. Meso- and metafemora with scattered punctures bearing short thickened, spine-like setae.
FIGURE 11. Aedeagi of Oocyclus spp in dorsal view: (a) O. ecolab sp. n. (holotype), (b) O. espinhacu sp. n. (paratype), (c) O.
giganteus sp. n. (holotype), (d) O. humboldti sp. n. (paratype), (e) O. lacia sp. n. (holotype), (f) O. ovalis sp. n. (holotype), (g)
O. sulcatus sp. n. (paratype), (h) O. thrixdiastematus sp. n. (holotype), (i) O. thysanus sp. n. (paratype).

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FIGURE 12. Elytral detail of Oocyclus spp. a) O. thysanus sp. n.; b) O. thrixdiastematus sp. n.; c) O. ovalis sp. n.; d) O.
sulcatus sp. n.; spr = systematic punctures row; int = elytral interval. Note in most cases, the rows of systematic punctures
can be detected by the presence of the setae; int1 is the sutural interval.
FIGURE 13. Elytral lateral surface of Oocyclus spp. a) O. ovalis sp. n.; b) O. sulcatus sp. n.; led = Longitudinal elytral
depression.
Abdomen. Ventrites covered with setae of varying lengths; ventrites 1–4 with scattered, long setae, distinctly
longer than longest setae on metaventrite, ventrite 5 more densely pubescent (Fig. 10b). Aedeagus: outer margin of
parameres weakly sinuous, gradually tapering to apex, curving inward; inner margin, straight, tapering from distal
half (dorsal view); median lobe shorter than parameres, with hooked apex. Gonopore apically on median lobe. Basal
piece rounded (Fig. 11i).
Etymology. The specific epithet is derived from thysanus = fringe (G) and refers to the first elytral row densely
set with erected setae. To be treated as a noun in apposition.
Distribution. Brazil (Minas Gerais) (Fig. 14).
Remarks. This species shares several diagnostic features with O. decorus (Kuwert, 1890): non-pale abdominal
ventrites, two prosternal spines, and elytra surface with distinct rows of systematic punctures bearing erect setae.
However, O. decorus has a weakly spinose posterolateral pronotal angle and brightly iridescent blue elytral macu-
lae, while O. thysanus sp. n. has the posterolateral margins of pronotum angulate, but not spinose and lacks brightly
iridescent blue elytral maculae.

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FIGURE 14. Distribution map for new Oocyclus species in Brazil.
New distributional records for Oocyclus species in Brazil (Fig. 15)
Oocyclus pilosus Jordão, Clarkson & Ferreira-Jr, 2018
Material examined. (4 exs.): “BRASIL: MINAS GERAIS, Parque Estadual Serra do Cabral, Waterfall of Demir,
long -44.211975 lat -17.920439, 833 m a.s.l., rock-face seepages, 14.iv.2019, leg. J.B.R. Alencar” (1 ex. INPA, in
alcohol); “PARNA Serra do Gandarela, Waterfall of Dona Chica, long -43.688806, lat -20.138139, 1165 m a.s.l.,
rock-face seepages, 14.vi.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); “Serro, Waterfall of Esteira, long
-43.492306, lat -18.571306, 1037m a.s.l., rock-face seepages, 31.iii.2020, leg. J.B.R. Alencar” (1 ex. INPA, in al-
cohol).
Remarks. First record of the O. pilosus from the state of Minas Gerais.
Oocyclus rotundus Clarkson & Short, 2012
Material examined. (380 exs.): “BRASIL: MINAS GERAIS, Diamantina, spring, long -43.743694, lat -18.077278,

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1350 m a.s.l., seepage habitat, 19.iv.2019, leg. J.B.R. Alencar” (1 ex. INPA, in alcohol); except: “long -43.6395,
lat -18.216528, 1246 m a.s.l., seepage habitat, 20.iv.2019, leg. J.B.R. Alencar” (1 ex. INPA, in alcohol); “long -
43.599111, lat -18.231333, 1221 m a.s.l., seepage habitat, 21.iv.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol);
“long -43.744639, lat -18.091639, 1359 m a.s.l., seepage habitat, 22.iv.2019, leg. J.B.R. Alencar” (9 exs. INPA, in
alcohol); “São João de Chapada, Estação Córrego próx. Copanor, long -43.731139, lat -18.089972, 1284 m a.s.l.,
seepage habitat, 22.iv.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); “PARNA Sempre Vivas, Stream south-
east of the camp, long -43.773861, lat -17.924444, 1259 m a.s.l., seepage habitat, 23.iv.2019, leg. J.B.R. Alencar”
(5 exs. INPA, in alcohol); “PARNA Sempre Vivas, Waterfall of Felipes, long -43.703639, lat -17.907472, 1090 m
a.s.l., rock-face seepages, 24.iv.2019, leg. J.B.R. Alencar” (5 exs. INPA, in alcohol); “Parque Estadual Grão Mogol,
Waterfall Véu de Noiva, long -42.954639, lat -16.595667, 793 m a.s.l., vertical surfaces with water, 27.iv.2019, leg.
J.B.R. Alencar” (59 exs. INPA, in alcohol); “Parque Estadual Grão Mogol, Waterfall of Mirante, long -42.899694,
lat -16.576639, 821 m a.s.l., vertical surfaces with water, 27.iv.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol);
“Parque Estadual Grão Mogol, Lapa da Água Fria, long -42.899556, lat -16.557083, 845 m a.s.l., vertical surfaces
with water, 27.iv.2019, leg. J.B.R. Alencar” (20 exs. INPA, in alcohol); “Parque Estadual Grão Mogol, stream near
the archaeological site, long -42.943556 lat -16.618111, 719 m a.s.l., rock-face seepages, 29.iv.2019, leg. J.B.R.
Alencar” (87 exs. INPA, in alcohol); “PARNA Serra do Cipó, Waterfall Capão dos Palmitos, long -43.609556, lat -
19.377472, 830 m a.s.l., rock-face seepage, 8.vi.2019, leg. J.B.R. Alencar” (5 exs. INPA, in alcohol); “PARNA Serra
do Cipó, Waterfall da Farofa, long -43.576139, lat -19.379389, 866 m a.s.l., vertical surfaces with water, 8.vi.2019,
leg. J.B.R. Alencar” (1 ex. INPA, in alcohol); “PARNA Serra do Cipó, Waterfall of Andorinhas, long -43.491472,
lat -19.237611, 1028 m a.s.l., vertical surfaces with water, 10.iv.2019, leg. J.B.R. Alencar” (25 exs. INPA, in alco-
hol); “PARNA Serra do Cipó, Canyon of the Bandeirinhas, long -43.562722, lat -19.423917, 880 m a.s.l., seepage
habitat, 11.vi.2019, leg. J.B.R. Alencar” (8 exs. INPA, in alcohol); “PARNA Serra do Gandarela, Waterfall of Dona
Chica, long -43.688806, lat -20.138139, 1165 m a.s.l., rock-face seepages, 14.vi.2019, leg. J.B.R. Alencar” (59 exs.
INPA, in alcohol); “PARNA Serra do Gandarela, Waterfall of Capivari, long -43.581639, lat -20.132639, 1257 m
a.s.l., seepage habitat, 17.vi.2019, leg. J.B.R. Alencar” (8 exs. INPA, in alcohol); “PARNA Serra do Gandarela, Wa-
terfall of Capivari, long -43.989917, lat -20.096611, 1335 m a.s.l., seepage habitat, 18.vi.2019, leg. J.B.R. Alencar”
(4 exs. INPA, in alcohol); “BRASIL: Minas Gerais, Serro, Waterfall of Amaral, long -43.406944, lat -18.388528,
1043 m a.s.l., vertical surfaces with water, 22.vi.2019, leg. J.B.R. Alencar” (52 exs. INPA, in alcohol); “Parque
Estadual Serra do Cabral, Córrego, long -44.182778, lat -17.781111, 683 m a.s.l., rock-face seepages, 23.vi.2019,
leg. J.B.R. Alencar” (3 exs. INPA, in alcohol); “Itacambira, Waterfall of Curiango, long -43.324861, lat -17.147556,
1051 m a.s.l., rock-face seepages, 24.vi.2019, leg. J.B.R. Alencar” (6 exs. INPA, in alcohol); “Rio de Contas,
Waterfall of Fraga, long -41.8295, lat -13.598194, 617 m a.s.l., 23.iii.2020, leg. J.B.R. Alencar” (4 exs. INPA, in
alcohol); “Serranópolis de Minas, Canyon near the Waterfall of Talhado, long -42.806389, lat -15.8175, 795 m a.s.l.,
27.iii.2020, leg. J.B.R. Alencar” (14 exs. INPA, in alcohol); “Botumirim, Cahoeira do Bananal, long -43.037042, lat
-16.839917, 908 m a.s.l., 28.iii.2020, leg. J.B.R. Alencar” (14 exs. INPA, in alcohol); “Serro, Waterfall de Esteira,
long -43.492306, lat -18.571306, 1037 m a.s.l., rock-face seepages, 31.iii.2020, leg. J.B.R. Alencar” (26 exs. INPA,
in alcohol); “BAHIA: PARNA Chapada Diamantina, Ribeirão do Meio, long -41.389194, lat -12.587639, 383 m
a.s.l., 28.vi.2019, leg. J.B.R. Alencar” (50 exs. INPA, in alcohol); “Piatã, Guarda-Mor, Waterfall Saia de Noiva, long
-41.867528, lat -13.311333, 1364 m a.s.l., 13.iii.2020, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); “GOIÁS: Alto
Paraíso de Goiás, Waterfall of muralha, long -47.7507, lat -14.2774, 957 m a.s.l., 2.VII.2019, leg. J.B.R. Alencar”
(4 exs. INPA, in alcohol).
Remarks. First record of O. rotundus for Goiás state. The specimens most recently collected are not dorsally
glabrous as illustrated by Clarkson & Short (2012), the elytral surface has rows of fine systematic punctures bear-
ing short setae similar to O. humboldti sp. n. but can be easily differentiated by the aedeagus (see diagnosis of O.
humboldti sp. n.).
Oocyclus xanthus Clarkson & Short, 2012
Material examined (7 exs.): “BRASIL: MINAS GERAIS, Serro, Waterfall de Esteira, long -43.492306, lat -
18.571306, 1037 m a.s.l., rock-face seepages, 31.iii.2020, leg. J.B.R. Alencar” (1 ex. INPA, in alcohol); “Per-
nambuco, Bonito, long -35.726722, lat -8.516972, 770 m a.s.l., 03.v.2014, leg. J.O. Silva; J.M.C. Nascimento; N.
Hamada,” (6 exs. INPA, in alcohol).

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 301
Remarks. First record of the O. xanthus Clarkson & Short, 2012 from the state of Pernambuco.
FIGURE 15. Distribution map for species of Oocyclus previously known in Brazil.
Oocyclus yubai Clarkson & Short, 2012
Material examined (1649 exs.): BRASIL: MINAS GERAIS, PARNA Serra do Cipó, Waterfall of Andorinhas,
long -43.491472, lat -19.237611, 1028 m a.s.l., vertical surfaces with water, 10.iv.2019, leg. J.B.R. Alencar" (15
exs. INPA; 10 exs. SEMC, in alcohol); except: Waterfall Capão dos Palmitos, long -43.609556, lat -19.377472,
830 m a.s.l., rock-face seepage, 8.vi.2019, leg. J.B.R. Alencar” (5 exs. INPA, in alcohol); "Waterfall Grande, long
-43.634333, lat -19.347056, 779 m a.s.l., vertical surfaces with water, 13.vi.2019, leg. J.B.R. Alencar” (10 exs.
INPA, in alcohol); “Parque Estadual Serra do Cabral, Waterfall of Boqueirão, long -44.178528, lat -17.758333, 680
m a.s.l., habitat higropétrico, 13.iv.2019, leg. J.B.R. Alencar” (41 exs. INPA, in alcohol); "Waterfall of Demir, long
-44.211975 lat -17.920439, 833 m a.s.l., rock-face seepages, 14.iv.2019, leg. J.B.R. Alencar” (118 exs. INPA, in
alcohol); "Waterfall of Fervedouro, long -44.247978, lat -17.917764, 1071 m a.s.l., rock-face seepages, 14.iv.2019,
leg. J.B.R. Alencar” (9 exs. INPA, in alcohol); "Augusto Lima, Waterfall Santa Bárbara, long -44.065583, lat -
18.031556, 616 m a.s.l., vertical surfaces with water, 15.vi.2019, leg. J.B.R. Alencar” (36 exs. INPA, in alcohol);
"Curimataí, Waterfall of Simão, long -43.955333, lat -17.896139, 650 m a.s.l., rock-face seepages, 16.iv.2019, leg.

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J.B.R. Alencar” (125 exs. INPA, in alcohol); "Caetemirim, Waterfall of Moinho, long -43.987889, lat -17.919472,
594 m a.s.l., vertical surfaces with water, 17.iv.2019, leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); "Caetemirim,
tributary of the Preto river, long -43.981217, -17.919472, 662 m a.s.l., vertical surfaces with water, 17.iv.2019, leg.
J.B.R. Alencar” (153 exs. INPA, in alcohol); "Diamantina, Stream of fazenda, long -43.769472, lat -18.062528,
1127 m a.s.l., vertical surfaces with water, 18.iv.2019, leg. J.B.R. Alencar” (12 exs. INPA, in alcohol); "Diaman-
tina, Stream of the Luiz Carlos, long -43.728417, lat -18.028611, 990 m a.s.l., seepage habitat, 19.iv.2019, leg.
J.B.R. Alencar” (1 ex. INPA, in alcohol); “Diamantina, São João de Chapada, Estação Córrego próx. Copanor,
long -43.731139, lat -18.089972, 1284 m a.s.l., seepage habitat, 22.iv.2019, leg. J.B.R. Alencar” (2 exs. INPA, in
alcohol); " Diamantina, Waterfall of Bocaina, long -42.837083, lat -16.301167, 669 m a.s.l., rock-face seepages,
28.iv.2019, leg. J.B.R. Alencar” (80 exs. INPA, in alcohol); "PARNA Sempre Vivas, Stream southeast of the camp,
long -43.773861, lat -17.924444, 1259 m a.s.l., seepage habitat, 23.iv.2019, leg. J.B.R. Alencar” (5 exs. INPA, in
alcohol); "PARNA Sempre Vivas, Waterfall of Felipes, long -43.703639, lat -17.907472, 1090 m a.s.l., rock-face
seepages, 24.iv.2019, leg. J.B.R. Alencar” (5 exs. INPA, in alcohol); "Parque Estadual Grão Mogol, stream near the
archaeological site, long -42.943556 lat -16.618111, 719 m a.s.l., rock-face seepages29.iv.2019, leg. J.B.R. Alencar”
(87 exs. INPA, in alcohol); "Parque Estadual Grão Mogol, Waterfall of Almas, long -42.931194, lat -16.618139, 691
m a.s.l., rock-face seepages, 29.iv.2019, leg. J.B.R. Alencar” (16 exs. INPA, in alcohol); "Parque Estadual Grão Mo-
gol, Stream of Dé, long -42.963833, lat -16.592361, 746 m a.s.l., rock-face seepages, 29.iv.2019, leg. J.B.R. Alen-
car” (17 exs. INPA, in alcohol); "Parque Estadual Grão Mogol, Waterfall of Almas, long -42.870111, lat -16.511139,
624 m a.s.l., rock-face seepages, 30.iv.2019, leg. J.B.R. Alencar” (29 exs. INPA, in alcohol); "Lassance, Waterfall of
Palmeiras, long -44.504167, lat -17.834333, 520 m a.s.l., vertical surfaces with water, 1.v.2019, leg. J.B.R. Alencar”
(2 exs. INPA, in alcohol); ""PARNA Serra do Gandarela, Waterfall of Viana, long -43.751472, lat -20.0975, 1078
m a.s.l., rock-face seepages, 14.vi.2019, leg. J.B.R. Alencar” (8 exs. INPA, in alcohol); ""PARNA Serra of Gan-
darela, Waterfall ofna Chica, long -43.688806, lat -20.138139, 1165 m a.s.l., rock-face seepages, 14.vi.2019, leg.
J.B.R. Alencar” (59 exs. INPA, in alcohol); ""PARNA Serra do Gandarela, Waterfall of Mingu, long -43.7596, lat
-20.0622, 1006 m a.s.l., rock-face seepages, 15.vi.2019, leg. J.B.R. Alencar” (44 exs. INPA, in alcohol); “Itabirito,
Corrego Prox a Fazenda Velha, long -43.809139, lat -20.299111, 862 m a.s.l., rock-face seepages, 20.vi.2019, leg.
J.B.R. Alencar” (25 exs. INPA, in alcohol); "Conceição of Mato Dentro, Waterfall of Três Barras, long -43.539833,
lat -19.335639, 701 m a.s.l., rock-face seepages, 21.vi.2019, leg. J.B.R. Alencar” (31 exs. INPA, in alcohol); "Serro,
Waterfall of Amaral, long -43.406944, lat -18.388528, 1043 m a.s.l., vertical surfaces with water, 22.vi.2019, leg.
J.B.R. Alencar” (52 exs. INPA, in alcohol); "Serro, Waterfall of Malheiros, long -43.4459, lat -18.6541, 738 m a.s.l.,
rock-face seepages, 31.iii.2020, leg. J.B.R. Alencar” (8 exs. INPA, in alcohol); "Serro, Waterfall of Esteira, long
-43.492306, lat -18.571306, 1037 m a.s.l., rock-face seepages, 31.iii.2020, leg. J.B.R. Alencar” (26 exs. INPA, in
alcohol); "Curimataí, Waterfall of Rio Curimataí, long -43.946806, lat -17.87825, 625 m a.s.l., vertical surfaces
with water, 23.vi.2019, leg. J.B.R. Alencar” (7 exs. INPA, in alcohol); "Gameleiras, Waterfall of Andorinhas, long
-43.079419, lat -14.981272, 931 m a.s.l., vertical surfaces with water and green algae, 24.iii.2019, leg. J.B.R. Alen-
car” (1 ex. INPA, in alcohol); "Mato Verde, Waterfall Maria Rosa, long -42.795444, lat -15.432167, 725 m a.s.l.,
vertical surfaces with water and green algae, 25.iii.2019, leg. J.B.R. Alencar” (46 exs. INPA, in alcohol); “Ser-
ranópolis de Minas, Waterfall Sete Quedas, vertical surfaces with water, 26.iii.2020, leg. J.B.R. Alencar” (6 exs.
INPA, in alcohol); "Botumirim, Waterfall Quatro Oitavas, long -43.014047, lat -16.883492, 862 m a.s.l., vertical
surfaces with water, 27.iii.2020, leg. J.B.R. Alencar” (9 exs. INPA, in alcohol); “Santo Antônio do Itambé, Rio
Preto, long -43.320778, lat -18.461417, 702 m a.s.l., vertical surfaces with water, 30.iii.2020, leg. J.B.R. Alencar”
(5 exs. INPA, in alcohol); "BAHIA: BA-564 Piatã-Mucugê, near the road, long -41.593139, lat -13.154611, 844
m a.s.l., vertical surfaces with water and green algae, 26.vi.2019, leg. J.B.R. Alencar” (149 exs. INPA, in alcohol);
"Mucugê Ponte-BA-142, near the road, long -41.351444, lat -12.989583, 881 m a.s.l., seepage habitat, 27.vi.2019,
leg. J.B.R. Alencar” (2 exs. INPA, in alcohol); “PARNA Chapada Diamantina, long -41.276139, lat -12.948639,
806 m a.s.l., seepage habitat, 27.vi.2019, leg. J.B.R. Alencar” (53 exs. INPA, in alcohol); “PARNA Chapada Dia-
mantina, long -41.358306, lat -12.700667, 388 m a.s.l., seepage habitat, 27.vi.2019, leg. J.B.R. Alencar” (66 exs.
INPA, in alcohol); “PARNA Chapada Diamantina, Andaraí, long -41.348639, lat -12.746972, 314 m a.s.l., seepage
habitat, 27.vi.2019, leg. J.B.R. Alencar” (31 exs. INPA, in alcohol); “PARNA Chapada Diamantina, Lençóis, long
-41.397444, lat -12.564167, 435 m al, 28.vi.2019, leg. J.B.R. Alencar” (139 exs. INPA, in alcohol); “PARNA Cha-
pada Diamantina, Ribeirão do Meio, long -41.389194, lat -12.587639, 383 m a.s.l., 28.vi.2019, leg. J.B.R. Alencar”
(50 exs. INPA, in alcohol); "Palmeiras, Waterfall of Riachinho, long -41.515694, lat -12.572111, 935 m a.s.l., verti-
cal surfaces with water, 18.iii.2020, leg. J.B.R. Alencar” (53 exs. INPA, in alcohol); “MATO GROSSO DO SUL:

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 303
Anastácio, Aquidauana (c. 27 km S) on MS-170, long -55.69127, lat -20.72281, 225 m elev., 27.vi.2018, seepage on
rock, leg. Hamada and team (10 exs. SEMC, INPA; pinned)”; “Aquidauana, Aquidauana (c. 15 km E) on plateau,
long -55.6218, lat -20.4509, 380 m elev., 22.vi.2019, detritus and roots at margin of rock, leg. Hamada and team”
(5 exs., SEMC, INPA; pinned).
Remarks. We expand the known distribution of this species to the states of Bahia, Minas Gerais and Mato
Grosso do Sul; this is also the first record of Oocyclus Sharp for the state of Mato Grosso do Sul. All adults exam-
ined are few punctures bear setae on the pronotum and elytra, thus the dorsal condition may appear glabrous
Checklist of the Oocyclus Sharp of Brazil
1. Oocyclus acuru Clarkson & Short, 2012 Brazil (ES)
2. Oocyclus aeneus Clarkson & Short, 2012 Brazil (MT)
3. Oocyclus alterosa Clarkson & Short, 2012 Brazil (ES, MG)
4. Oocyclus caparao Clarkson & Short, 2012 Brazil (ES, MG)
5. Oocyclus decorus (Kuwert, 1890) Brazil (RJ, SP)
6. Oocyclus ecolab sp. n. Brazil (MG)
7. Oocyclus espinhacu sp. n. Brazil (MG)
8. Oocyclus flexus Clarkson & Short, 2012 Brazil (SC)
9. Oocyclus fryanus Balfour-Browne, 1939 Brazil (RJ, SP)
10. Oocyclus giganteus sp. n. Brazil (MG)
11. Oocyclus humboldti sp. n. Brazil (GO, MG)
12. Oocyclus iguazu (Oliva, 1996) Argentina, Brazil (MG, PR, SP), Paraguay,
Paraguay (Paraguari District)
13. Oocyclus itapecori Clarkson & Short, 2012 Brazil (ES, MG, SP, RJ)
14. Oocyclus itapecum Clarkson & Short, 2012 Brazil (SP, PR, SC)
15. Oocyclus lacia sp. n. Brazil (MG)
16. Oocyclus ovalis sp. n. Brazil (MG)
17. Oocyclus pilosus Jordão, Clarkon & Ferreira-Jr, 2018 Brazil (MT, MG)
18. Oocyclus rotundus Clarkson & Short, 2012 Brazil (GO, MG, RJ, SP)
19. Oocyclus schubarti d’Orchymont, 1940 Argentina*, Brazil (AL)
20. Oocyclus sulcatus sp. n. Brazil (MG)
21. Oocyclus thrixdiastematus sp. n. Brazil (GO, BA, MG)
22. Oocyclus thysanus sp. n. Brazil (BA)
23. Oocyclus xanthus Clarkson & Short, 2012 Brazil (PE, MG, RJ)
24. Oocyclus yubai Clarkson & Short, 2012 Brazil (MG, BA, MT, MS, PR, RJ, SC, SP),
Paraguay (Paraguari District)
*Need confirmation
Updated key to the Brazilian species of Oocyclus Sharp
This key is adapted from Clarkson & Short (2012) and includes also an additional species from Jordão et al.
(2018).
1 Prosternal carina with two or more spine-like setae (Figs. 3e, 9e) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
- Prosternal carina without spine-like setae (see Jordão et al., (2018): Fig. 2a ................................O. pilosus
2 Posterolateral angles of pronotum usually rounded (very rarely angulate) (Figs. 2, 4); prosternum with two or more spine-like
setae; elytra with or without iridescent maculae, if present, maculae never blue; elytra with or without rows of erect setae . . 3
- Posterolateral angles of pronotum weakly spinose (see Clarkson & Short, 2012: Fig. 5); prosternum always with two spine-like
setae; elytra with distinctive blue maculae and a dense row of erect setae (Fig. 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . O. decorus
3 Prosternal carina set with 2 spine-like setae anteriorly (Figs. 2, 7) ..............................................12
- Prosternal carina set with more than 2 spine-like setae anteriorly (usually 4–6; Figs. 3, 6) ............................4
4 Elytral surface heavily sculptured to appear bumpy or strongly undulating; glabrous (see Clarkson & Short, 2012: Figs. 1, 3)
...................................................................................................5

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- Elytral surface smooth, without bumps or strong undulations; glabrous or set with setae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5 Elytral surface appearing blistered (see Clarkson & Short, 2012: Fig. 3) .................................. O. alterosa
- Elytral surface with irregular sculpturing, but without distinctly raised bumps (see Clarkson & Short, 2012: Fig. 1) ........
............................................................................................ O. acuru
6 Elytra with setae between rows of systematic punctures, appearing pubescent (Fig. 12b) .............................7
- Elytra with weak or non-existent pubescence between rows of systematic punctures (Figs. 12a, c, d) ................... 8
7 Posterolateral angles of pronotum rounded. Elytra pubescence decumbent laterally and on elytral intervals, but with at least two
erect rows of setae medially. Posterior margin of the elytra darkly coloured, except for the pale spot on posterior quarter (see
Clarkson & Short, 2012: Fig. 9) .................................................................O. itapercori
- Posterolateral angles of pronotum angulate. Elytra pubescence decumbent; not forming distinct rows medially. Posterior margin
of elytra broadly depigmented medially (see Clarkson & Short, 2012: Fig. 13) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. xanthus
8 Posterolateral margins of pronotum angulate (see Clarkson & Short, 2012: Fig. 4); elytral surface with very shallowly im-
pressed longitudinal grooves near suture .......................................................... O. caparao
- Posterolateral margins of pronotum broadly rounded; elytral surface with or without very shallowly impressed longitudinal
grooves near suture .................................................................................... 9
9 Elytra with strong indentation mediolaterally (see Clarkson & Short, 2012: Fig. 7); body attenuated posteriorly . . O. fryanus
- Elytra without or with only weak indentation mediolaterally; body not attenuated posteriorly ........................10
10 Elytra surface with shallowly impressed longitudinal grooves; (e.g. Figs. 6a–e); each elytron with two or more posterior, small
rounded pale spots ..........................................................................O. lacia sp. n.
- Elytra surface without shallowly impressed longitudinal grooves or with weak undulating grooves near sutural interval; each
elytron with a single posterior, rounded pale spot ...........................................................11
11. Elytra with undulating grooves near the sutural interval; TL/GW ratio = 1.65; abdominal ventrites with color strongly contrast-
ing to the legs (e.g. Figs. 3a–e) ............................................................ O. espinhacu sp. n.
- Elytra without undulating grooves near the sutural interval; TL/GW ratio = 1.80; abdominal ventrites never in strong contrast
to the legs ..................................................................................O. itapecum
12 Elytra surface with fine punctures (see Clarkson & Short, 2012: Figs. 2, 6); elytral suture raised or not .................13
- Elytra surface coarsely punctures (see Clarkson & Short, 2012: Fig. 8); elytral suture raised .........................14
13 Posterolateral margins of pronotum angulate, but never spinose (Figs. 4c, 10c) ....................................15
- Posterolateral margins of pronotum rounded ...............................................................16
14 Elytra with large, coarse punctures coarsely punctuate and without undulating grooves; posterolateral margins of pronotum
angulate ......................................................................................O. iguazu
- Elytra with moderately sized, coarse punctures and with undulating grooves; posterolateral margins of pronotum rounded (e.g.
Figs. 8a–e) ............................................................................ O. sulcatus sp. n.
15 Elytra with conspicuous rows of systematic punctures, row 1 bearing long, erect setae in contrast to row 2 (Figs. 10a–e, 12a);
body size 4.7–5.4 mm; aedeagus as in Fig. 11i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. thysanus sp. n.
- Elytra with hardly distinguishable rows of systematic punctures, rows 1 and 2 with similar setae; body size 5.7–6.3 mm; ae-
deagus as in Fig. 11c (e.g. Figs. 4a–e) ...................................................... O. giganteus sp. n.
16 Abdominal ventrites dark brown to black, similar in color to thoracic venter (see Clarkson & Short, 2012: Figs. 2, 6); elytral
suture raised or not on posterior half; elytral margins slightly reflexed or not . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
- Abdominal ventrites uniformly pale yellow or orange, distinctly darker than thoracic venter (see Clarkson & Short, 2012: Fig.
14) and in many cases with distinct medial macula present on one or more ventrites (e.g. Fig. 5b); elytral suture not raised on
posterior half; elytral margins not reflexed on posterior half . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
17 Each elytron with one rounded pale spot on distal quarter ....................................................21
- Each elytron with two rounded pale spots on distal quarter .................................................... 22
18 Elytra without a row of large black spots alongside the suture (e.g. Fig. 5a) ......................................19
- Elytra with a row of large black spots alongside the suture (e.g. Fig. 6a) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
19 Elytra surface without setae; abdominal ventrites uniformly pale from yellow to orange (see Clarkson & Short, 2012: Fig. 11)
.......................................................................................... O. rotundus
- Elytra surface with setae; one or more abdominal ventrites in many cases with distinct medial macula as wide as or narrower
than respective ventrites (e.g. Figs. 5a–e) ...................................................O. humboldti sp. n.
20 Thoracic venter and legs brown and slightly darker than abdominal ventrites (see Clarkson & Short, 2012: Fig. 12) ........
......................................................................................... O. schubarti
- Thoracic venter and legs dark brown to black and strongly contrast to the yellow abdominal ventrites (see Clarkson & Short,
2012: Fig. 14) .................................................................................O. yubai
21 Elytral suture not raised on posterior half; elytral margins not reflexed on posterior half ............................ 23
- Elytral suture raised on posterior half; elytral margins weakly reflexed on posterior half .......................O. flexus
22 Elytral intervals with dense pubescence inserted in ground punctation (Fig 12b); aedeagus with gonopore located on medial half
of median lobe, basal piece tapered (Fig. 11h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O. thrixdiastematus sp. n.
- Elytral interval with weak or non-existent pubescence inserted in ground punctation (Figs. 12a, c, d); aedeagus with gonopore
located at four-fifths the length of median lobe, basal piece rounded (Fig. 11a) . . . . . . . . . . . . . . . . . . . . . . . . . O. ecolab sp. n.
23 Metaventrite with oval, glabrous posteromedial area about half the length of metaventrite; aedeagus as in Figs. 2, 15b, in Clark-
son & Short (2012) ............................................................................ O. aeneus
- Metaventrite with oval, glabrous posteromedial area about two-thirds the length of metaventrite; aedeagus as in Figs. 11f (Fig.
7a–e) .................................................................................. O. ovalis sp. n.

NEW OOCYCLUS FROM BRAZIL Zootaxa 5087 (2) © 2022 Magnolia Press · 305
Acknowledgments
Financial support was provided by CNPq/PROTAX (440616/2015-8); FAPEAM (PROTAX and POSGRAD pro-
grams); MCTI/ INPA; Coordination for the Improvement of Higher Education Personnel (CAPES). NH is CNPq
research fellow (308970/2019-5) and J.B.R.A. receive a PhD fellowship from CAPES. The following institutions
provided the collections permits: Ministério do Meio Ambiente (MMA), Instituto Chico Mendes de Conservação
da Biodiversidade (ICMBio), Sistema de Autorização e Informação em Biodiversidade (autorization 67613-1);
Instituto do Meio Ambiente e Recursos Hídricos, Coordenação de Gestão das Unidades de Conservação INEMA/
DG/DIRUC/COGES do Estado da Bahia; Instituto Estadual de Florestas (IEF), Secretaria de estado de meio
ambiente e desenvolvimento sustentável do estado de Minas Gerais (autorization 015/2019). Hugo Cesar Soares,
Ítalo Kaíque, José Wilson, Jeferson Silva (INPA) helped with the expedition execution and field work. Creuza dos
Santos, Sophia Galvier, Raimundo Cordeiro, Rafael Hiago, Laércio Azevedo, Marcelo Henrique, Scheker Barbosa,
Winicius Moura, Robson Augusto, Renato Antônio and Juan Pereira helped us to find the streams, during sampling
procedures. We sincerely thank M. Bento and anonymous reviewers for their valuable comments and constructive
criticisms which have greatly improved the manuscript.
References
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