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A new species of Oxyrhopus Wagler, 1830 (Serpentes: Dipsadidae) from the Bolivian Andes


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We describe a new dipsadine snake species, of the genus Oxyrhopus Wagler, 1830, from the highlands of Bolivia. Oxyrhopus emberti sp. n. is diagnosed from its congeners based on external and hemipenial morphology. The new species inhabits the humid forests of Yungas and Tucumano-Bolivian Forest highlands, between 1.200-1.800 meters above sea level, and is likely to be a Bolivian endemic. We also discuss the relationships of the new species with Andean congeners and provide a key to the identifi cation of the Oxyrhopus species from the Central Andes of Bolivia and Peru.
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An Acad Bras Cienc (2020) 92(Suppl. 2): e20191428 DOI 10.1590/0001-3765202020191428
Anais da Academia Brasileira de Ciências | Annals of the Brazilian Academy of Sciences
Printed ISSN 0001-3765 I Online ISSN 1678-2690 |
An Acad Bras Cienc (2020) 92(Suppl. 2)
Running title: NEW Oxyrhopus
Academy Section: BIOLOGICAL
(Suppl. 2)
92(Suppl. 2)
A new species of Oxyrhopus Wagler, 1830
(Serpentes: Dipsadidae) from the Bolivian Andes
Abstract: We describe a new dipsadine snake species, of the genus Oxyrhopus Wagler,
1830, from the highlands of Bolivia. Oxyrhopus emberti sp. n. is diagnosed from its
congeners based on external and hemipenial morphology. The new species inhabits
the humid forests of Yungas and Tucumano-Bolivian Forest highlands, between 1.200
– 1.800 meters above sea level, and is likely to be a Bolivian endemic. We also discuss
the relationships of the new species with Andean congeners and provide a key to the
identifi cation of the Oxyrhopus species from the Central Andes of Bolivia and Peru.
Key words: Pseudoboini, systematics, taxonomy, Xenodontinae.
Within neotropical caenophid snakes, one
of the most diverse and enigmatic groups is
the Pseudoboini tribe, that encompasses the
genera Boiruna Zaher, 1999, Clelia Fitzinger,
1826, Drepanoides Dunn, 1926, Mussurana
Zaher, Grazziotin, Cadle, Murphy, de Moura-
Leite & Bonatto, 2009, Oxyrhopus Wagler,
1830, Paraphimophis Zaher, Grazziotin, Cadle,
Murphy, de Moura-Leite & Bonatto, 2009,
Phimophis Cope, 1860, Pseudoboa Schneider,
1801, Rodriguesophis Zaher, Grazziotin, Murphy,
Scrocchi, Benavides, Zhang, & Bonatto, 2012,
Rhachidelus Boulenger, 1908, and Siphlophis
Fitzinger, 1843, and is supported by several
morphological and molecular synapomorphies
(Bailey 1970, Zaher 1999, Lynch 2009, Grazziotin
et al. 2012, Alencar et al. 2013, Gaiarsa et al.
2013). Despite many works on taxonomy and
systematics of these genera, there remain many
poorly resolved or supported relationships,
taxonomically unstable species, or even
paraphyletism problems, issues that are largely
related to the currently incomplete evaluation
of species boundaries, morphological and
molecular variation (Zaher 1994, Sheehy et al.
2012, Figueroa et al. 2016).
The genus Oxyrhopus Wagler, 1830
represents a polyphyletic conglomerate of 14
nocturnal, small to moderate sized species, and
widely distributed across the Neotropical region,
occurring in pluvial forests, open formations,
desertic areas, and oceanic islands, from
southern Mexico, to northern Argentina (Alencar
et al. 2013, Uetz 2019, Zaher et al. 2009, 2019).
T he species of Oxyrhopus share an undivided
cloacal scale, paired subcaudals, a temporal
formulae of 1+2 or 2+3, 7-10 infralabials and
7-8 supralabials, as well as a deeply bilobed,
bicalyculate and bicapitated hemipenis, also
presenting enlarged and well-developed lateral
spines, in three or four rows, usually with a
nude area in the lateral region of each lobe
(Peters & Orejas-Miranda 1970, Zaher 1999);
these characteristics, however, are not exclusive
to Oxyrhopus, and the genus remains without
a diagnosis. Five species (Oxyrhopus formosus
(Wied), Oxyrhopus guibei Hoge & Romano,
Oxyrhopus petolarius (Linnaeus), Oxyrhopus
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 2 | 14
rhombifer Duméril, Bibron & Duméril, and
Oxyrhopus melanogenys (Tschudi)) have
confirmed records to Bolivia (Fugler et al. 1995,
Embert 2007). Another congener, Oxyrhopus
trigeminus Duméril, Bibron & Duméril, presents
unconfirmed and unvouchered records to
Bolivia (Nogueira et al. 2019); its occurrence in
Bolivia is treated herein as probable.
While examining snake specimens from
the Yungas and Tucumano-Bolivian Forests,
we encountered a large series of a distinctive
Oxyrhopus species, with unique coloration and
morphology, that could not be assigned to any
described species. After a detailed comparison
with all its congeners, we concluded it represents
a new species, easily diagnosed by morphology.
We describe the species and provide brief
comments on the taxonomy of Andean
Oxyrhopus, suggesting that a comprehensive
taxonomic and systematic review should be
realized to clarify the status of some poorly
known congeners.
The ZooBank Life Science Identifier
(LSID) of this publication is: urn:lsid:zoobank.
We examined 56 preserved specimens (Appendix
I) from the following collections: Coleção
Herpetológica Universidade de Brasília (CHUNB),
Brazil; Instituto Butantan (IBSP), Brazil; Coleção
Herpetológica Museu de Ciências e Tecnologias
PUCRS (MCP), Brazil; Museo Noel Kempff Mercado
(MNKR), Bolivia; Colección Boliviana de Fauna
en La Paz, (CBF) Bolivia; Coleção Herpetológica
Universidade Federal do Rio Grande (CHFURG),
Brazil; Field Museum of Natural History (FMNH),
United States; The Louis Agassiz Museum of
Comparative Zoology (MCZ), United States; Museu
de Zoologia Universidade Federal de São Paulo
(MZUSP), Brazil; Zoologisches Forschungsinstitut
und Museum Alexander Koenig en Bonn (ZFMK),
Germany; Centro de Biodiversidad y Genética
Reptiles en Cochabamba (CBGR), Bolivia. Of these,
28 specimens (11 adult females, 5 adult males,
2 juvenile females, 4 juvenile males, 6 unsexed
juveniles) were identified as an undescribed taxon.
Comparative morphological data was also
obtained from Peters & Orejas-Miranda (1970),
Zaher (1999), Freitas (2003), and Lynch (2009).
We follow standard terminology for describing
scalation and coloration (Peters 1964, Peters &
Orejas-Miranda 1970, Savage & Slowinski 1992).
Dentition was examined in eight specimens, and
described by exposing and counting teeth over
both maxillae; these specimens are indicated
with an asterisk mark (*). Hemipenial preparation
and terminology follows Zaher (1994, 1999).
Measurements of snout-vent length (SVL) and
tail length were taken with a flexible ruler (to
the nearest 1 mm), while head, eye and scale
were taken with a dial caliper (to the nearest
0,05 mm). Standards for adult (mature) or
juvenile (immature) individuals follows Pizzatto
& Marques (2002), as defined for O. guibei
[juvenile females present a total body length
(SVL + TL) smaller than 632 mm, and juvenile
males 388 mm]. Sex was determined either by
subcaudal incision or through visual inspection
of everted hemipenes. A ratio of ventral per
subcaudal scales was calculated by dividing
each ventral scale count by its subcaudal scale
count. Measurements and meristic counts
were unavailable for damaged or incomplete
specimens. Other used abbreviations are: SD=
standard deviation, n= number of specimens.
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 3 | 14
Oxyrhopus emberti Gonzales, Reichle &
Entiauspe-Neto, sp. n.
ZooBank Life Science Identifier (LSID) -
MNKR 2551* (Figs. 1, 2, and 6). Adult female,
collected 15/01/98, at Santa Rosa de Lima (17,87°
W,64,25° S), Provincia Florida, Departamento
Santa Cruz, Bolivia, by Francisco Sagot.
Paratypes (25 specimens)
Bolivia: Departamento Cochabamba: provincia
Ayopaya: Cotacajes-Altamachi (16,48° W, 66,78°
S): CBGR 0061: adult female, unknown collection
date. Provincia Carrasco: Road between Antena
Entel y Limbo (no coordinates): MNKR 3727:
juvenile female, collected on 07/03/05. Provincia
Tiraque: Chaquisaca (17,41° W,65,24° S): CBGR
701: adult male, collected on 1/11/09.
Departamento Chuquisaca: provincia Luis
Calvo: Río Ticucha (19,60° W,63,88° S): MNKR
3616: unsexed juvenile, collected on 11/04/04.
Departamento Santa Cruz: provincia Florida:
La Hoyada (17,92° W,64,12° S): MNKR 2625:
unsexed juvenile, collected on 18/11/03; MNKR
3506: juvenile female, collected on 20/12/02;
MNKR 3493: adult female, collected on 29/03/03;
MNKR 3537: adult female, collected on 25/12/02.
Los Monos (no coordinates): MNKR 4344: juvenile
male, collected on 21/04/07. Palmasola (17,89°
W,64,21° S): MNKR 1488*: adult female, collected
on 25/02/98; MNKR 1531*; adult female, collected
on 22/11/97; MNKR 2237*: adult female, collected
on 15/07/99; MNKR 1506*: adult male, collected
on 20/01/98. Palmasola, Paraje Yunga de las
Doncellas (no coordinates): MNKR 4336: unsexed
juvenile, collected on 03/06/04. Pampagrande
(18,1 W,64,1 S): MNKR 3522: unsexed juvenile,
collected on 16/05/02; MNKR 3544: unsexed
juvenile, collected on March 2003. Samaipata
(18,18° W,63,86° S): MNKR 2971: adult female,
collected on 24/11/02. San José (Pampagrande)
(18,1° W,64,1° S): MNKR 2684*: adult female,
collected on 14/06/01. Santa Rosa de Lima
(17,87° W,64,25° S): MNKR 2421*: adult female,
collected on 19/07/2001; MNKR 3415: unsexed
juvenile, collected on 17/10/02. Sivingalito
(no coordinates): MNKR 2058*: adult female,
collected on 5/12/99. Verdugo: MNKR 1223: adult
male, collected on 12/12/96. Aguaclarita (17,99°
W,64,09° S): MNKR 4714: unsexed juvenile, no
collection data. Provincia Vallegrande: Pampas
(Postrervalle) (no coordinates): MNKR 4825:
juvenile male, collected on 12/11/09. Provincia
Cordillera: Yupa (19,8° W,63,7° S): MNKR 4369:
juvenile male, collected on 26/11/07.
Referred specimens (2 specimens)
Departamento La Paz: Provincia Caranavi: Serranía
Bellavista: Road between Caranavi and Yucumo
(15,7° W,67,47° S): ZFMK 80614 (AJ03/6): unsexed
adult, collected on March 2003; ZFMK 80615
(AJ03/44): juvenile male, collected on March 2003.
Figure 1. Dorsal view of Oxyrhopus emberti (MNKR 2551,
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 4 | 14
Oxyrhopus emberti sp. nov can be distinguished
from all its congeners based on: (1) smooth
dorsal scales with two apical pits, 19/19/17 rows;
(2) postoculars two; (3) loreal rectangular, wider
than higher; (4) temporal formula 2+3, 1+3 (or
rarely 1+2); (5) supralabials usually eight, with
4th and 5th (rarely 4th, 5th, and 6th) in contact
with orbit; (6) infralabials nine or ten (rarely
eight), with 4–5 in contact with first pair of
genials; (7) ventrals 197–209 in females, 189–195
in males; (8) subcaudals 66–74 in females, 75–87
in males; (9) in life, dorsum uniform black in
adults, juveniles present alternating large black
bands, with cream bands on tail and anterior
third of body, including nuchal region, bands
changing to orange on posterior body (body
black bands 4–17 scales wide; body white bands
1–4 scales wide; tail black bands 3–8 scales
wide; tail white bands 1–3 scales wide); (10)
in life, venter uniform black with yellow gular
region in adults, dorsal bands continue onto
venter in juveniles; (11) juveniles with black body
bands 17–29 and white body bands 16–21, black
tail bands 6–11 and white tail bands 7–10; (12)
maximum TTL in females 1277 mm and males 916
mm; (13) maxillary teeth 15:13 smooth and two
grooved teeth; (14) supraocular and prefrontal
in contact, separating preocular from frontal;
(15) hemipenis strongly bilobed, bicalyculate,
bicapitate, with lateral spines developed and
enlarged, in five rows.
Characteristics from other species are presented
in parentheses in this section. Oxyrhopus
emberti sp. n. can be readily distinguished
from O. melanogenys, O. guibei, O. trigeminus,
Oxyrhopus melanogenys orientalis Cunha and
Nascimento, 1983, and Oxyrhopus vanidicus
Lynch, 2009 by preocular scale separated from
frontal by a supraocular and prefrontal contact
(preocular in contact with frontal); in adults of
O. emberti uniform black dorsum dorsum and
venter, juveniles with narrow orange or white
body bands (diads or triads of black body bands)
(Cunha & Nascimento 1983, Zaher & Caramaschi
1992, Freitas 2003, Lynch 2009).
Oxyrhopus emberti differs from O. petolarius
by preocular separated from frontal by
supraocular and prefrontal contact (preocular in
contact with frontal); subcaudals in males 75–87, in
Figure 2. Head views of Oxyrhopus emberti (MNKR 2551,
holotype). Illustration by Arthur Tiutenko.
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 5 | 14
females 66–74 (100–126 in males, 86–110 in females
of O. petolarius); uniform black adult dorsum and
venter (alternating black and red body bands with
white venter; although it might have a uniform
black dorsum in some individuals, it retains a
white venter) (Cunha & Nascimento 1983, Freitas
2003, Lynch 2009); only papillate calyces present
on asulcate and sulcate medial surfaces (enlarged
spines widely present on asulcate and sulcate
medial surfaces) (Zaher 1999); maxillary teeth 13+2
(8+2) (MacCulloch et al. 2009).
Oxyrhopus emberti may be distinguished
from O. occipitalis by uniform black adult
coloration (red with faint black bands, yellow
snout and gular region, top of head brown);
maxillary teeth 13+2 (7–8+2) (Hoge et al. 1977,
Cunha & Nascimento 1989, MacCulloch et al.
Oxyrhopus emberti may be distinguished
from O. formosus by maximum range of
ventrals reaching up to 209 (191); dorsal scale
rows 19/19/17 (19/19/19); snout black (yellow,
orange, or red), adults uniform black (black
and reticulated red or white crossbands, venter
white); juvenile body bands reaching up to 29 in
body, 11 in tail (19 and 8) (Hoge et al. 1977, Cunha
& Nascimento 1989, Silva Jr 1993, Freitas 2003).
Oxyrhopus emberti may be distinguished
from O. rhombifer by preocular separated from
frontal by supraocular and prefrontal contact
(preocular in contact with frontal); white nuchal
collar in juveniles (red in juveniles and adults);
adults uniform black (black crossbands or
triangles over incomplete red and white bands);
hemipenis strongly bilobed with conspicuous
pair of nude pockets in the lobular crotch
(moderately bilobed, with moderately developed
nude pockets) (Cei 1993, Zaher 1999, Freitas 2003).
Oxyrhopus emberti may be distinguished
from O. clathratus by presenting a nude area in
lateral region of the tip of hemipenial lobes, five
rows of enlarged spines, and organ Y-shaped
(ornamented with papillate calyces, four rows
of enlarged spines, either T or Y-shaped);
adults uniform black (alternating red, white,
and black crossbands, adults sometimes with
black dorsum, with a white venter); (Zaher 1999,
Bernardo et al. 2012).
Oxyrhopus emberti may be distinguished
from O. doliatus in having dorsal scale rows
19/19/17 (19/19/19); adult uniformly black (red
with broad black rings anteriorly, diminishing in
width posteriorly) (Zaher & Caramaschi 2000).
Oxyrhopus emberti may be distinguished
from O. fitzingeri by dorsal scale rows 19/19/17
(vs. 19/19/19); adults uniform black, crossbands
in juveniles (light brown with irregular and
scattered dark brown blotches, head pale
orange) (Peters & Orejas-Miranda 1970).
Oxyrhopus emberti may be distinguished
from O. leucomelas by dorsal scale rows
19/19/17 (17/17/15); higher range of infralabials
8–10 (7–8); uniform black dorsum in adults and
crossbands in juveniles (alternating black and
white crossbands, with a vertebral orange stripe)
(Peters & Orejas-Miranda 1970).
Oxyrhopus emberti may be distinguished
from O. marcapatae by supralabials 8–9 (7);
dorsal scale rows 19/19/17 (15/15/15); adults
uniform black (alternating black and cream
bands) (Ruthven in Barbour 1913, Peters &
Orejas-Miranda 1970, Gaiarsa et al. 2013).
Oxyrhopus emberti may be distinguished
from O. erdisii by dorsal scales in 19/19/17 rows,
with two apical pits (19/19/15 rows without apical
pits); broad white nuchal collar in juveniles,
absent in adults (incomplete narrow cream
nuchal collar, in juveniles and adults); adults
uniform black, juveniles with black and white or
orange crossbands (juveniles and adults with
alternating black, white or red crossbands);
larger first black band in juveniles, 9–17 scales
wide (5–8 scales wide) (Zaher & Caramaschi
2000) (Figs. 3 and 6).
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 6 | 14
Description of holotype
Adult female, SVL 1044 mm, tail length 233 mm
(22.3% SVL); head slightly distinct from body;
head length 34.8 mm (3.33% SVL); head width
18.8 mm (54% head length); rostral scale wider
(6.0 mm) than higher (4.9 mm); distance between
internasals 3.3 mm, less than distance between
edge of prefrontals (5.6 mm). Prefrontals
paired, pentagonal, contacting internasals,
loreals, preoculars, supraoculars, and frontal.
Interparietal suture slightly shorter than frontal
scale, and much shorter than distance from
anterior frontal margin to rostral tip. Frontal
scale triangular, with slightly curved edges, width
8.2 mm, length 6.0 mm. Supraoculars length 5.7
mm, width 3.2 mm. Nasal divided, higher than
wide. Loreal rectangular, width 3.7 mm, height
1.8 mm. Preocular single, height 2.9 mm, than
width 2.0 mm; postoculars two, similar in size
and shape; temporals 2 + 3; supralabials 8/8,
2nd and 3rd in contact with loreal, 3rd and 4th
in contact with preocular, 4th and 5th in contact
with orbit; infralabials 10/10, first pair in contact
with distal border of mental, 1-4 in contact with
anterior genial, 5th and 6th larger and in contact
with posterior genial. Posterior genials length
6.2 mm / 5.8 mm, than anterior 7.9 mm / 7.3 mm;
dorsal scales smooth, with two apical pits, in
19/19/17 rows; ventrals 209; cloacal scale single;
subcaudals in 69 pairs; eye diameter 3.1 mm,
snout-orbit distance 10.7 mm; pupil vertical;
maxillary teeth 13/13, followed by a distema, and
then two grooved teeth.
The specific epithet “emberti” is a noun in
genetive case, and honours German herpetologist
Figure 3. Comparison between
similar Oxyrhopus species from
Central and Northern Andes. a:
Juvenile individual of Oxyrhopus
erdisii from Chachabamba-
Winaywayna, Bolivia (UTA
R-51470) ; b: Juvenile individual of
Oxyrhopus erdisii in preservative
from Chachabamba (UTA-R 51469);
c: Topotypical adult individual
of Oxyrhopus erdisii in life from
Macchu Picchu, Peru (Unvouchered);
d: Holotype of Oxyrhopus erdisii in
preservative from Macchu Picchu,
Peru (MCZ 8829); e: Oxyrhopus
doliatus in preservative from Pauji,
Venezuela (MCZ 49031, Holotype
of O. venezuelanus); f: Oxyrhopus
marcapatae from Macchu Picchu,
Peru (MCZ 8831, Holotype of
Drepanodon eatonii). Photo credits:
Carl J. Franklin (a, b), Harvey Rogoff
(c), Joseph Martinez (d, f).
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 7 | 14
Dirk Embert, who has provided extensive
contributions to the Bolivian Herpetology.
Largest male SVL 916 mm; largest female SVL 1277
mm (holotype). Ventral scales 189–209 (mean =
199; SD = 6.72; n = 25); in males, 189–195 (mean =
191; SD = 3.46; n = 3), in females, 197–209 (mean =
204; SD = 3.32; n = 13). Subcaudals 62–87 (mean =
73; n = 16); in males, 75–87 (mean = 82; SD = 6.11;
n = 3), in females 66–74 (mean = 70; SD = 3.25; n =
13). Most individuals have eight supralabials (n =
22), rarely nine (n = 2; MNKR 3506, 3537), with 4th
and 5th (n = 22) or rarely 4th, 5th, and 6th (MNKR
3506, 3537) in contact with orbit. Infralabials
eight (n = 1), nine (n = 16), or 10 (n = 7), with
1st–4th (n = 12) or 1st–5th (n = 12) in contact
with first pair of genials. Examined specimens
presented temporal formulae 1 + 2 (n = 1), 1 + 3 (n
= 9), or 2 + 3 (n = 15). Ventral/subcaudal relation
ranges from 30–46% (males, 40–46%, mean = 43;
females, 32–36¨, mean = 34). Relation between
tail length and total length ranges from 16–23%
(males, 23–23%, mean = 22.81; females, 17–20%,
mean = 18.27). All examined specimens had 13
maxillary teeth, a single prediastemal teeth, and
two grooved postdiastemal teeth.
Hemipenial morphology
Strongly bilobed, bicalyculate, bicapitate,
elongated, with lobes half as long as hemipenial
body (Fig. 4). Lateral spines enlarged, in five
rows, converging to distal ends of an enlarged
crest, present on medial surface of both lobes.
A pair of moderately developed naked pockets
in the lobular crotch, under the enlarged crest.
Sulcus spermaticus proximally bifurcated,
dividing on proximal part of hemipenial body,
becoming centrifugal, and conduced directly to
upper portion of organ. Lobes are ornamented
with papillate calyces, spinulate over border of
capitulum. As in most of Oxyrhopus species, O.
emberti sp. nov presents a nude area on lateral
region of each lobe; in the new species, it is
poorly developed.
The 10 examined juvenile specimens (MNKR 2625,
3415, 3522, 3544, 3616, 4336, 4369, 4714, 4825, ZFMK
80615) of undetermined sex, and two juvenile
females (MNKR 3506, 3727), exhibited banded
pattern, consisting of black body bands 17–29
and white body bands 16–21, black tail bands
6–11 and white tail bands 7–10); in one specimen,
MNKR 3544, black color does not extend onto
venter anteriorly; white bands 1-4 scales wide
dorsally, wider on venter; separated by black
bands of 4–17 scales; head black dorsally, with a
broad and complete red or yellow nuchal collar
in juveniles; one juvenile female (MNKR 3506,
537 mm total body length) is almost fully black,
with a yellow gular region, and white body bands
visible on the last body third and tail, dorsally
and ventrally; the other juvenile female (MNKR
3727, 565 mm TTL) is completely black, with a
yellow gular region.
Some small adult individuals (e.g. CBGR
0061, 1032 mm total body length) conserve
red incomplete bands, although indistinct or
vestigial, turning white on alcohol; an adult
male (MNKR 1506, 450 mm) has a uniform black
dorsum, and a dark yellow venter; all other
adult individuals present uniform black dorsum
and venter, with a pale yellow gular region;
supralabials are black, and infralabials are pale
yellow, as in the gular area; iris coloration red. In
preservative, yellow turns white.
Geographic distribution and natural history
The new species is known only from humid
rainforests, from 1.200–1.800 m above sea level. It
is known from 11 localities, all in humid rainforests
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 8 | 14
of Yungas and Tucumano-Bolivian ecorregions,
and is currently endemic to Bolivia (Fig. 5).
Most specimens were collected during
rainy season (June to February, 14 specimens),
in March (2 specimens) and May (1 specimen).
Three juvenile males were collected in May,
November, and December. An adult female
(MNKR 2058) collected in December contained
nine eggs in its oviduct, while another (CBGR
0061) collected in November contained six eggs.
A rodent (Muridae) was in the stomach content
of a specimen (MNKR 2551, adult female). One
juvenile specimen (MNKR 4336) has a second
head, slightly malformed on the right side of the
neck, slightly smaller than the normal head and
seemingly non-functional.
The description of Oxyrhopus emberti sp. n.
raises the number of valid Oxyrhopus species to
15. The genus Oxyrhopus presents an intricate
taxonomic history and systematic relationships,
being considered as polyphyletic (Zaher 1994,
Sheehy et al. 2012, Figueroa et al. 2016). Although
fitting the morphological diagnosis of Oxyrhopus
(Peters & Orejas-Miranda 1970, Zaher 1999), an
integrated taxonomic revision of Oxyrhopus is
needed; noteworthy examples are O. marcapatae,
that presents a strikingly different morphological
characterization, differing from other Oxyrhopus
species by presenting 15 dorsal rows, 7
supralabials, and 8 infralabials (vs. more than
15 dorsal rows with or without reduction, except
for O. leucomelas, 8 or more supralabials except
for O. leucomelas, 9 or more supralabials except
for O. leucomelas), and O. leucomelas, which
presents unique morphological characters (7 or
8 supralabials and infralabials, 17/17/15 dorsal
rows) and shares hemipenial similarities and a
similar coloration pattern with Siphlophis species
(Zaher 1999, Lynch 2009, Sheehy et al. 2012).
The new species appears to be most
morphologically similar to O. erdisii, which
is currently known to its type locality, in the
lowland Amazon Rainforests of the Macchu
Picchu mountain range, Cusco department,
southern Peru (Zaher & Caramaschi 2000).
Both species share several similarities in
hemipenial morphology (hemipenis elongated,
strongly bilobed, bicalyculate, bicapitate, lobes
ornamented with papillate calyces and spinules
Figure 4. Hemipenial
morphology of Oxyrhopus
emberti sp. n (MNKR 1223).
Asulcate side (Left) and
sulcate side (Right).
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 9 | 14
over the border of the capitulum, with poorly
developed nude areas at the tip of lobes)
and juvenile coloration pattern (both present
monadal pattern and nuchal collars); we have
also examined specimens of O. erdisii (Appendix
1) from the lowland Amazon Rainforests of
Sandia, Puno department, southeastern Peru
close to the Bolivia border, and unvouchered
live specimen, tentatively assigned as Oxyrhopus
cf. erdisii from the Yungas of Chulumani, La
Paz department, in Bolivia, approximately 360
km S from the southernmost record (Fig. 7b,
d). Likewise, O. formosus also shares with O.
emberti and O. erdisii elongated and strongly
bilobed hemipenis, with poorly developed nude
areas at the tip of lobes. Other two species
that present similarities with O. emberti are O.
clathratus (occurs in Montane Atlantic Rainforest
of Argentina and Brazil, share similar scale
counts in dorsal scale rows, supralabials and
infralabials, and a monadal band pattern, with
melanistic adult individuals), and O. petolarius
(widely distributed in South America, share
similar adult and juvenile coloration). However,
O. clathratus and O. petolarius present white
ventral coloration, even in melanistic specimens.
Melanistic individuals have been widely
reported for O. clathratus and O. petolarius
(Bernardo et al. 2012); as both O. emberti and
O. clathratus occur in montane areas, the
melanistic coloration may reflect an adaptation
to increase thermoregulatory capacity, as there
is a debate whether darker colors and its
reflectance difference may influence a rate in
which solar radiation is converted into body
heat (see Forsman 1995, Bernardo et al. 2012).
The new species inhabits humid
rainforests of Yungas and Tucumano-Bolivian
ecorregions, and is currently endemic to Bolivia.
Considering its restricted range, we suggest
that O. emberti should be considered as a
candidate for a threatened species status, and
further assessments on its conservation and
populational trends are warranted. In agreement
with other authors (e.g. Zaher 1999, Zaher et al.
2009, 2019), we also highlight the need for a
genus-wide systematic and taxonomic revision
based on integrative data sets, to elucidate the
phylogenetic relationships of this new species,
and other exquisite congeners.
Figure 5. Geographic
distribution of some
Central Andes Oxyrhopus:
Oxyrhopus emberti sp. n
(Star), Oxyrhopus cf. erdisii
(Square), Oxyrhopus erdisii
(Circles). Type locality of
O. emberti (Red star), type
locality of O. erdisii (Red
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 10 | 14
Dichotomous key for Oxyrhopus on the central
Andes Mountains
1a. Dorsal rows 15, supralabials 7, with
3rd and 4th in contact with orbit…………O.
1b. Not as above ..................................................2
2a. Dorsal pattern with alternating, diads,
or triads of black bands………………………………3
2b. Not as above...................................................6
3a. Background body coloration red with
black reticules, red nuchal collar, disperse
black triads O. melanogenys
3b. Not as above..................................................4
4a. Body with complete black bands in
diads or triads, black head, yellow nuchal
collar, orange or yellow body bandsO.
4b. Not as above .................................................5
5a. Body with groups of complete black
bands in diads or triads, separated by
red rings, usually visible on the venterO.
Figure 6. Coloration of Oxyrhopus
emberti in life. a: Adult specimen
(MNKR 2551, holotype) from Santa
Rosa de Lima, Provincia Florida,
Departamento Santa Cruz, Bolivia;
b: Juvenile specimen (MNKR
4825); c: Unvouchered adult from
Departamento Santa Cruz, Bolivia;
d: Head close of same individual;
e: Dorsal view of same individual;
f: Unvouchered juvenile from
Muyupampa-Ipati, Departamento
Santa Cruz, Bolivia; g: Same previous
individual, ventral view. Photo
credits: Daniel Alarcón (c, e), Oscar
Johnson (f, g).
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 11 | 14
5b. Body with vestigial or
conspicuous alternating black ban
6a. Adults light brown with irregular
and scattered light blotches, head pale
orange, 19 dorsal rows………………….....O.
6b. Not as above ...............................................7
7a. Head mostly black dorsally in adults....8
7b. Head light brown, usually incomplete
white nuchal collar…………………………O. erdisii
8. Fully black adult individuals, 19/19/17
dorsal scales with two apical pits, juveniles
with monadal pattern, preocular not in
contact with frontal………… O. emberti sp. n.
8b. Not as above....................................................9
9a. Dorsum with triangular or semicircular
black blotches, with red and yellow
background coloration…………………………O.
9b. Black and red monadal bands on
dorsum, white venter…………………………O.
10a. Head coloration white, yellow or
red, cream snout coloration, vestigial
or conspicuous transverse black body
bands……………………………................O. formosus
10b. Head coloration black, orange
nuchal collar, alternating black and
white crossbands with a orange vertebral
stripe………………………………..........O. leucomelas
Figure 7. Comparison of Oxyrhopus cf. erdisii and Oxyrhopus emberti. a: Juvenile specimen of O. emberti (MNKR
4369) from Departamento Santa Cruz, Bolivia; b: Unvouchered juvenile O. cf. erdisii from La Paz, Bolivia (note its
narrower black bands); c: Unvouchered adult O. cf. erdisii from La Paz, Bolivia; d: Adult female O. cf. erdisii from La
Paz, Bolivia (MNKR, voucher unavailable). Photo credits: Mauricio Pacheco (d).
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 12 | 14
We would like to thank the staff of Museu de Historia
Natural Noel Kempff Mercado for assisting in the analysis
of the specimens under their care. We are deeply
indebted to A. Resetar (FMNH), C. J. Franklin (UTA), J.
Campbell (UTA), D. Rivera (CBGR), D. Loebmann (CHFURG),
G. M. F. Pontes (MCP), J. Martinez (MCZ), J.Rosado (MCZ), J.
Aparicio (CBF) and R. Aguayo (CBGR), who kindly provided
access, data, and photographs on the specimens under
their care. We are also grateful to R. D. MacCulloch and
two anonymous reviewers, for their contributions and
constructive criticism to our manuscript. A. Tiutenko
(Arthur Tiutenko Nature Images) kindly provided a fine-
art illustration our holotype. M. Pacheco, O. Johnson,
and D. Alarcón provided photographs for our study. The
community of Pampagranda municipality and Florida
province, in special for the missing Fray Andrés Langer
(†), significantly contributed for enriching biological
collections, and were very helpful for our study.
ALENCAR LR, GAIARSA MP & MARTINS M. 2013. The evolution
of diet and microhabitat use in Pseudoboine snakes. S
Am J Herpetol 8(1): 60-67.
BAILEY JR. 1970. Oxyrhopus. In: Peters JA and Orejas-
Miranda B (Eds), Catalogue of the Neotropical Squamata:
Part 1, Snakes. U.S. National Museum 297, Washington,
p. 229-235.
BARBOUR T. 1913. Reptiles collected by the Yale Peruvian
expedition of 1912. P Acad Nat Sci Phila: 505-507.
Redescription and Morphological Variation of Oxyrhopus
clathratus Duméril, Bibron and Duméril, 1854 (Serpentes:
Dipsadidae: Xenodontinae). S Am J Herpetol 7: 134-148.
CEI JM. 1993. Reptiles del noroeste, nordeste y este de
la Argentina. Herpetofauna de las Selvas subtropicales,
Puna y Pampas. Museo Regionale di Scientia Naturale
Torino, Monografia 14, 949 p. (Unpublished data).
DA CUNHA OR & NASCIMENTO FP. 1983. Ofidios da Amazonia
XIX: As espécies de Oxyrhopus Wagler, com uma
subespécie nova, e Pseudoboa Schneider, na Amazonia
oriental e Maranhão. (Ophidia: Colubridae). Bol Mus Para
Emílio Goeldi Zool 122: 49 p.
EMBERT D. 2007. Distribution, Diversity and Conservation
Status of Bolivian Reptiles. Unpublished PhD Thesis.
Rheinische Friedrich Wilhelms University, Bonn,
Germany, 430 p.
2016. A species-level phylogeny of extant snakes with
description of a new colubrid subfamily and genus. PloS
ONE 11(9): e0161070.
FORSMAN A. 1995. Heating rates and body temperature
variation in melanistic and zigzag Vipera berus: does
colour make a difference? Ann Zool 32: 365-374.
FREITAS MA. 2003. Serpentes Brasileiras. Malha-de-Sapo
Publicações e Consultoria Ambiental, Lauro de Freitas,
160 p.
FUGLER CM, DE LA RIVA I & CABOT J. 1995. Herpetología
Boliviana Una lista comentada de las serpientes de
Bolivia con datos sobre su distribución. Ecol Boliv 24:
GAIARSA MP. 2013. Natural history of Pseudoboine snakes.
Pap Avulsos de Zool 53(19): 261-283.
MA, ZHANG YP & BONATTO SL. 2012. Molecular phylogeny of
the new world Dipsadidae (Serpentes: Colubroidea): a
reappraisal. Cladistics 28(5): 437-459.
HOGE AR & ROMANO SARWDL. 1977. Description of a new
subspecies of Oxyrhopus Wagler (Serpentes, Colubridae).
Mem Inst Butantan 40/41: 55-62.
LYNCH JD. 2009. Snakes of the genus Oxyrhopus
(Colubridae: Squamata) in Colombia: taxonomy and
geographic variation. Pap Avulsos de Zool 49(25): 319-337.
M. 2009. The genus Oxyrhopus (Serpentes: Dipsadidae:
Xenodontinae) in Guyana: morphology, distributions
and comments on taxonomy. Pap Avulsos de Zool 49(36):
NOGUEIRA CC ET AL. 2019. Atlas of Brazilian snakes: verified
point-locality maps to mitigate the Wallacean shortfall
in a megadiverse snake fauna. S Am J Herpetol 14: 1-274.
PETERS JA. 1964. Dictionary of Herpetology. Hafner
Publishing Company, New York, New York, USA, 392 p.
PETERS JA & OREJAS-MIRANDA B. 1970. Catalogue of the
Neotropical Squamata. Part I. Snakes. Bull Am Mus Nat
Hist 297: 1-347.
PIZZATTO L & MARQUES OAV. 2002. Reproductive Biology of
the false coral snake Oxyrhopus guibei (Colubridae) in
southeastern Brazil. Amphibia-Reptilia 23: 495-504.
SAVAGE JM & SLOWINSKI JB. 1992. The colouration of the
venomous coral snakes (family Elapidae) and their
mimics (families Aniliidae and Colubridae). Biol J Linn
Soc Lond 45(3): 235-254.
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 13 | 14
A new species of Siphlophis (Serpentes: Dipsadidae:
Xenodontinae) from the eastern Andean slopes of
Ecuador. S Am J Herpetol 9(1): 30-46.
SILVA JR NJ. 1993. The snakes from Samuel hydroelectric
power plant and vicinity, Rondônia, Brazil. Herp Nat Hist
1(1): 37-86.
UETZ P & HOŠEK J. 2019. The Reptile Database. Available
from [Accessed in 16
November 2019].
WAGLER J. 1830. Natürliches System der Amphibien, mit
vorangehender Classification der Säugthiere und Vögel.
München. J. G. Cotta., 354 p.
ZAHER H. 1994. Phylogénie des Pseudoboini et évolution
des Xenodontinae sud-américains (Serpentes,
Colubridae). (Ph.D. Dissertation). Mus Hist Nat Paris.
ZAHER H. 1999. Hemipenial Morphology of the South
American Xenodontine Snakes, with a proposal for
a monophyletic Xenodontinae and a reappraisal of
Colubrid hemipenis. Bull Am Mus Nat Hist 240: 1-168.
ZAHER H & CARAMASCHI U. 1992. Sur Le Statut Taxinomique
d‘Oxyrhopus trigeminus et O. guibei (Serpentes,
Colubridae). Bull Mus Natl Hist Nat 4: 805-827.
ZAHER H & CARAMASCHI U. 2000. Synonymisation of
Oxyrhopus venezuelanus Shreve, 1947, with Oxyrhopus
doliatus Dumeril, Bibron & Dumeril, 1854, and
revalidation of Oxyrhopus erdisii (Barbour, 1913)
(Serpentes, Colubridae). Dumerilia 4(2): 113-122.
ZAHER H ET AL. 2019. Large-scale molecular phylogeny,
morphology, divergence-time estimation, and the fossil
record of advanced caenophidian snakes (Squamata:
Serpentes). Plos ONE 14: e0216148.
JC & BONATTO SL. 2009. Molecular phylogeny of advanced
snakes (Serpentes, Caenophidia) with an emphasis on
South American Xenodontines, A revised classification
and descriptions of new taxa. Pap Avulsos de Zool 49:
Additional material examined:
Oxyrhopus clathratus (n = 1): BRAZIL: RIO GRANDE
DO SUL: Bento Gonçalves (MCP 5117).
Oxyrhopus erdisii (n = 7): PERU: Unknown locality
(FMNH 40068), CUSCO: Macchu Picchu (MCZ
8829, holotype), Macchu Picchu Arqueological
Site (Unvouchered), URUBAMBA: Chachabamba
(UTA R-51469), Chachabamba-Winaywayna (UTA
R-51470), PUNO: Sandia: Sandia (UTA R-59045),
Santo Domingo (FMNH 39370).
Oxyrhopus cf. erdisii (n = 1): BOLIVIA: LA PAZ:
Chulumani (MNKR, without voucher).
Oxyrhopus doliatus (n = 1): VENEZUELA: FALCON:
Distrito Acosta: Pauji (MCZ 49031, Holotype of O.
Oxyrhopus guibei (n = 1): BRAZIL: BAHIA:
Correntina (CHUNB 03655).
Oxyrhopus marcapatae (n = 2): PERU: CUSCO:
Macchu Picchu (MCZ 8831, holotype of
Drepanodon eatonii, BMNH 1946.1.8.72, holotype
of Oxyrhopus marcapatae).
Oxyrhopus melanogenys (n = 1): BRAZIL:
AMAZONAS: Estação Ecológica Juami-Japurá
(MCP 19495).
Oxyrhopus vanidicus (n = 5): BRAZIL: AMAPÁ:
Macapá (CHFURG 5699). PERU: HUANUCO:
Cayumba Valley (FMNH 5589), LORETO: Upper
Amazon (FMNH 11194, 11195, 11196).
Oxyrhopus melanogenys orientalis (n = 1):
BRAZIL: CEARÁ: Ubajara (IBSP 77061).
Oxyrhopus petolarius (n = 6): BRAZIL: BAHIA:
Elísio Medrado (MZUSP w/n), Santa Maria da
Vitória (Photographic voucher), MATO GROSSO:
U.H.E. Guaporé, São Domingos (MCP 14021,
14022), RIO DE JANEIRO: Sítio 13, Taquara, Duque
de Caxias (CHFURG 4873, 4874).
Oxyrhopus rhombifer (n = 1): BRAZIL: RIO GRANDE
DO SUL: Rio Grande (CHFURG 5966).
Oxyrhopus trigeminus (n = 1): BRAZIL: BAHIA:
Cocos (CHFURG 51118).
How to cite
of Oxyrhopus Wagler, 1830 (Serpentes: Dipsadidae) from the
Bolivian Andes. An Acad Bras Cienc 92: e20191428. DOI 10.1590/0001-
An Acad Bras Cienc (2020) 92(Suppl. 2) e20191428 14 | 14
Manuscript received on December 9, 2019;
accepted for publication on September 7, 2020
1Museo Historia Natural Noel Kempff Mercado,
Avenida Irala, 556, Santa Cruz, Bolivia
2Universidade Federal do Rio Grande, Instituto de Ciências
Biológicas, Laboratório de Vertebrados, Avenida Itália,
km 8, Vila Carreiros, 96203-900 Rio Grande, RS, Brazil
Correspondence to: Omar Machado Entiauspe-Neto
Author contributions
LG and SR collected specimens in field and wrote manuscript
draft, OME-N wrote manuscript draft.
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