A new species of the genus Dexipeus Pascoe, 1885 (Coleoptera, Curculionidae) from the Philippines

Abstract

A new species, Dexipeus krasilnikovi sp. nov. from Luzon (Philippines) is described and
illustrated. This new species is very similar to D. uenoi Morimoto, 1978 but differs in the less coarsely punctate pronotum, with the apical constriction, without middle carina, and the rostrum distinctly longer than the pronotum. A key and distribution map for species of the genus Dexipeus are given. It is the first record of the genus Dexipeus from the Philippines.

Full text

175
Baltic J. Coleopterol. 21(2) 2021
ISSN 1407 - 8619
INTRODUCTION
The tribe Strombocerini is presented by 46 de-
scribed species from 12 genera from the Oriental
Region (Alonso-Zarazaga et al., 2017;
Grebennikov, 2018a, 2018b, 2018c; Legalov, 2019,
2020b, 2021a, 2021b). The genus Dexipeus
Pascoe, 1885 differs from other genera in the lin-
ear eyes narrowly separated ventrally, 6-seg-
mented funicle and obliquely truncate antennal
club (Morimoto, 1978). This genus includes three
described species, D. fumosus Pascoe, 1885 from
Java and D. costatus from Sumatra, Indonesia
(Pascoe, 1885), and D. uenoi Morimoto, 1978 is
from Okinawa, Japan (Morimoto, 1978) and the
new species from the Philippines.
A new species of the genus Dexipeus Pascoe, 1885 (Coleoptera,
Curculionidae) from the Philippines
Andrei A. Legalov
Legalov A.A. 2021. A new species of the genus Dexipeus Pascoe, 1885 (Coleoptera,
Curculionidae) from the Philippines. Baltic J. Coleopterol. 21(2): 175 - 180.
A new species, Dexipeus krasilnikovi sp. nov. from Luzon (Philippines) is described and
illustrated. This new species is very similar to D. uenoi Morimoto, 1978 but differs in the less
coarsely punctate pronotum, with the apical constriction, without middle carina, and the rostrum
distinctly longer than the pronotum. A key and distribution map for species of the genus
Dexipeus are given. It is the first record of the genus Dexipeus from the Philippines.
Key words: Curculionoidea, Dryopththorinae, Strombocerini, Luzon.
Andrei A. Legalov. Institute of Systematics and Ecology of Animals, Siberian Branch, Russian
Academy of Sciences, Frunze street-11, Novosibirsk 630091 Russia; e-mail:
fossilweevils@gmail.com
Altai State University, Lenina-61, Barnaul 656049 Russia.
Tomsk State University, Lenina Prospekt, 36, Tomsk 634050 Russia.
In this paper, the new species of the genus
Dexipeus from Luzon is described.
MATERIAL AND METHODS
Type specimen is kept in the ISEA = Institute of
Systematics and Ecology of Animals (Russia:
Novosibirsk). Descriptions, body measurements,
and photographs, were prepared using the Zeiss
Stemi 2000-C dissecting stereomicroscope. The
terminology of the weevil body structure is ac-
cording to Lawrence et al. (2010). The systemat-
ics of studied taxa are based on the works of
Grebennikov (2018a) and Legalov (2020a).

176
Legalov A.A.
RESULTS
Genus Dexipeus Pascoe, 1885
Dexipeus krasilnikovi sp. nov.
(Fig. 1)
Type material: Holotype. Male (ISEA), North
Luzon, Ifugao, Banaue, X.2016.
Paratypes. Female (ISEA), idem, IV.2016; male
(ISEA), North Luzon, Ifugao, Hungduan, III.2018;
female (ISEA), North Luzon, Mt. Province,
Bontoc, I.2014; male (ISEA), idem, IX.2014; fe-
male (ISEA), idem, I.2015; female (ISEA), idem,
I.2018; female (ISEA), idem, II.2018.
Description. Male. Body black, with matted pu-
bescence. Antennae, apex of tibiae and tarsi red-
brown. Head subconical. Mandibles small. Ros-
trum long, weakly longer than pronotum, about
4.0 times as long as wide at apex and at midlength,
about 3.6 times as long as wide at base, distinctly
curved, densely punctate. Apex of rostrum finely
punctate. Eyes large, linear, not protruding from
contour of head, narrowly separated ventrally.
Forehead flat, about 0.5 times as long as rostrum
base width. Antennal scrobes directed ventrally
to base of rostrum. Antennae inserted near mid-
dle of rostrum. Scape long, 4.6 times as long as
wide in apex, not reaching eye. Funicle 6-seg-
mented. Antennomeres 2 and 3 subconical.
Antennomere 2 about 1.7 times as long as wide
in apex, 0.3 times as long as scape. Antennomere
3 0.9 times as long as wide in apex, 0.5 times as
long as and slightly narrower than antennomere
2. Antennomeres 4-7 wide-conical. Antennomere
4 0.5 times as long as wide in apex, 0.6 times as
long as and 1.1 times as wide as antennomere 3.
Antennomere 5 0.4 times as long as wide, 0.8
times as wide as and slightly wider than
antennomere 4. Antennomere 6 0.3 times as long
as wide, 0.8 times as long as and slightly wider
than antennomere 5. Antennomere 7 0.3 times as
long as wide, equal in length and 1.1 times 1.2
times as wide as antennomere 6. Antennal club
compact, obliquely truncate, about 1.7 times as
long as wide, about 0.8 times as long as
antennomeres 2-7 combined, with tomentose
apex. Pronotum campanulate, with apical con-
striction, 1.5 times as long as wide at apex, about
1.1 times as long as wide at midlength, about 1.2
times as long at pronotal base. Pronotal disk
weakly convex dorsally, coarsely punctate, with-
out carina in middle. Intervals between points
smaller than their diameter. Sides weakly nar-
rowed from apical third towards base. Maximum
width in middle. Base of pronotum slightly nar-
rower than base of elytra. Scutellum small, trian-
gular. Elytra almost subparallel, at base 2.0 times
as long as wide, at midlength about 1.4 times as
long as wide, at apical fourth 2.1-2.2 times as long
as wide, 1.9-2.0 times as long as pronotum. Hu-
meri weakly flattened. Elytral striae distinct, with
large punctation. Stria 9 short, fused with stria 10
at level of metacoxae. Interstriae convex, narrow,
0.5-0.8 times as narrow as striae, pilose. Odd
interstriae with fully matted pubescence.
Prosternum punctate, with weak rostral channel,
without postocular lobes. Precoxal portion of
prosternum slightly longer than procoxal cavity.
Postcoxal portion of prosternum short. Procoxal
cavities contiguous. Mesocoxal cavities narrowly
separated. Metanepisternum absent.
Metaventrite about 2.5 times as long as length of
metacoxa, flattened, punctate. Abdomen weakly
convex ventrally, punctate. Ventrite 1 1.5 times
as long as length of metacoxa. Ventrite 2 about
0.8 times as long as ventrite 1. Ventrite 3 0.5 times
as long as ventrite 2. Ventrite 4 shorter than
ventrite 3. Ventrite 5 about 1.2 times as long as
ventrite 4, densely punctate. Pygidium impressed
in middle. Procoxae subconical. Mesocoxae
spherical, narrowly separated. Metacoxae trans-
verse. Femora slightly thickened, without tooth.
Metafemora not extending beyond apex of ab-
domen. Tibiae weakly curved, with large uncus.
Tarsi long. Tarsomeres 1-3 conical, with erect
setae ventrally. Tarsomere 5 elongate. Tarsal
claws free, divergent. Total body length (with-
out rostrum) 3.4-3.8 mm. Length of rostrum 0.9-
1.0 mm.
Female. Rostrum 3.9-4.0 times as long as wide at
apex, 4.1-4.2 times as long as wide at midlength,
about 3.6 times as long as wide at base. Pronotum
1.2 times as long as wide at apex, about 0.9 times

177
A new species of the genus Dexipeus Pascoe, 1885 (Coleoptera, Curculionidae) from the Philippines
Fig. 1. Dexipeus krasilnikovi sp. nov.: a – holotype, male, habitus, dorsally, b – paratype, female,
habitus, dorsally, c – holotype, aedeagus and tegmen, dorsally, d – holotype, male, habitus, laterally,
e – paratype, female, habitus, laterally. Scale bar for a, b, d, e = 1.0 mm, for c = 0.5 mm.

178
Legalov A.A.
as long as wide at midlength and at pronotal base.
Elytra at base 1.8 times as long as wide, at
midlength about 1.6-1.7 times as long as wide, at
apical fourth about 2.2 times as long as wide,
about 2.7 times as long as pronotum. Andominal
ventrites 1 and 2 more convex. Total body length
(without rostrum) 3.7-4.1 mm. Length of rostrum
1.0-1.1 mm.
Diagnosis. This new species is similar to D. uenoi
from Okinawa but differs in the less coarsely
Fig. 2. Distribution of the genus Dexipeus: star – D. uenoi, rhombus – D. fumosus, octagon – D.
krasilnikovi sp. nov., square – D. costatus.
punctate pronotum, with the apical constriction,
without middle carina, and the rostrum distinctly
longer than the pronotum.
Etymology. The species is named in honor of
Vladislav A. Krasilnikov (Mariinsky Posad, Rus-
sia).
Distribution. Philippines: Luzon (fig. 2).

179
A new species of the genus Dexipeus Pascoe, 1885 (Coleoptera, Curculionidae) from the Philippines
Key to species of the genus Dexipeus
1. Odd elytral interstriae with fully matted pubescence.............................................................................2
- Punctation on all elytral interstriae with white pubescence....................................................................3
2. Pronorum coarsely punctate, subcylindrical, with middle carina. Rostrum subequal to pronotum.
..............................................................................................................................................................D. uenoi
- Pronotum less coarsely punctute, with apical constriction, without middle carina. Rostrum dis-
tinctly longer than pronotum.....................................................................................D. krasilnikovi sp. nov.
3. Pronotum finely punctate, with subparallel sides.................................................................D. costatus
- Pronotum coarsely punctate, with weakly rounded sides........................................................D. fumosus
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Received: 12.10.2021
Accepted: 21.12.2021
Published: 30.12.2021