Revision of the mainland species of the Neotropical genus Aegidium Westwood (Coleoptera: Scarabaeidae: Orphninae)
Author
Frolov, Andrey V.
Author
Akhmetova, Lilia A.
Author
Vaz-de-Mello, Fernando Z.
text
Journal of Natural History
2017
2017-05-17
51
19 - 20
1035
1090
http://dx.doi.org/10.1080/00222933.2017.1319519
journal article
10.1080/00222933.2017.1319519
7dd54e06-5524-476c-8ef1-eefc5c571da3
1464-5262
4746652
Aegidium colombianum
Westwood, 1845
(
Figures 2
(a–g) and 3(a–c))
Aegidium colombianum
Westwood 1845: 174
Aegidium colombianum
Westwood
:
Lacordaire 1856: 131
;
Gemminger and Harold 1869: 1073
;
Preudhomme de Borre 1886: 24
;
Bates, 1887: 105
;
Arrow, 1903: 515
,
1904: 738
,
1912: 31
;
Heyne and Taschenberg 1907: 72
;
Schmidt, 1913: 70
;
Paulian 1984
:
Aegidium elongatum
Paulian, 1984
,
syn. nov.
Type
locality
Colombia
.
Type
material examined
Aegidium columbianum
:
lectotype
,
here designated
(
Figure 2
(a,d,e)): male at
OUMNH
labeled ‘
Aegidium Columbianum
Westw. Trans. Ent. Soc.
4. P.174. Pl 12
Figures 7–8
Columbia/TYPE COL: 486
Aegidium columbianum
Westw. HOPE DEPT.OXFORD
/Co-TYPE WESTWOOD Trans. Ent. Soc. 4. 1864. P.174. T
12 f.
7–8/W’.
Aegidium elongatum
:
holotype
(
Figure 3
(a–c)): male at
BMNH
labeled ‘Colombia 75–36/Columb./3922/Holotype/
Aegidium elongatum
n.s. R.Paulian/HOLOTYPE’; paratype: female at MNHN labelled ‘
Aegidium columbianum
West. Caracas/
Aegidium elongatum
n
. sp. R.Paulian det./ALLOTYPE/MUSEUM PARIS’.
Additional material examined
COLOMBIA
: without precise locality,
two males
at
BMNH
,
one male
at
IRSNB
,
two males
at
MHNG
,
nine males
and
three females
at
MNHN
,
one male
and
one female
at
OUMNH
,
two males
and
one female
at
RMNHL
,
two males
at
ZIN
,
four males
and
one female
at
ZMUKK
.
VENEZUELA
.
Distrito Capital
:
Caracas
,
one male
at
BMNH
,
one male
and
one female
at
CNCI
,
three males
at
MNHN
,
one female
at
OUMNH
,
one male
at
ZIN
,
three males
and
three females
at
ZMUKK
;
without precise locality,
seven males
and
four females
at
BMNH
,
one female
at
IRSNB
,
one male
and
one female
at
MHNG
,
one male
and
one female
at
NHMB
and
one female
at
ZIN
.
BRAZIL
: without precise locality,
one male
at
ZIN
,
one male
at
IRSNB
.
NO LOCALITY:
one male
at
BMNH
,
14 males
at
MNHN
and
one male
at
OUMNH
.
CHILI
: without precise locality,
one male
at
BMNH
(doubtful record)
.
Diagnosis
Aegidium columbianum
can be separated from other
Aegidium
species
by the shape of the parameres (
Figures 2
(d,e) and 3(b,c)) and endophallic armature consisting of two strongly sclerotised hook-shaped sclerites and one asymmetrical y-shaped sclerite (
Figure 2
(b)).
Description
Male (
Figures 2
(a) and 3(a)). Body length 11.5–20.0 mm. Colour uniformly blackish brown.
Anterior margin of frontoclypeus slightly convex in middle, slightly sinuate each side of medial convexity, rounded laterally, without distinct border. Frontoclypeus punctate with rounded punctures separated by 1–2 puncture diameters.
Eyes relatively large: width about 1/7 distance between eyes in dorsal view.
Pronotum with widely rounded lateral margins, wider than elytra, 1.6 times wider than length, 0.55 times length of elytra. Posterior angles widely rounded, indistinct. Anterior margin bordered, border interrupted medially and not reaching anterior angles. Base of pronotum without furrow, punctate with a row of large, rounded, punctures separated by about 1 puncture diameter. Pronotal disc deeply excavated, with flattened area mediobasally. Lateral pronotal processes long, horn-shaped in lateral view, protruding past lateral margin outline of pronotum in dorsal view. Pronotum almost smooth: lateral processes almost impunctate, medial excavation punctate with sparse rounded punctures.
Scutellum narrow subtriangular, about 1/12 length of elytra.
Elytra 1.2 times longer than wide, with humeral and apical umbones. Elytra widest in basal 1/3, tapering apically in dorsal view. Elytral carinae weak, indistinct. Elytra covered with relatively sparse, rounded punctures separated by 2–3 puncture diameters at sides and somewhat denser, elongate punctures on disc.
Macropterous.
Mesotibiae without tuft of setae ventroapically. Inner apical spur of mesotibia shorter than basal mesotarsomere and not curved downwards.
Aedeagus with relatively long (0.66 times length of phallobase) parameres. Apices of parameres widened in dorsal view and curved downwards (
Figures 2
(d) and 3(b)). Parameres wider than apical part of phallobase in dorsal view. Ventrobasal transverse plate of parameres distinct. Lateral teeth of parameres large, strongly protruding past paramere outline in dorsal view (
Figures 2
(e) and 3(c)). Endophallus with 2 symmetrical, hook-shaped sclerites and 1 asymmetrical y-shaped sclerite (
Figure 2
(b)). Cranial part of spiculum gastrale relatively wide, slightly tapering, rounded to truncate apically (
Figure 2
(f)).
Female (
Figure 2
(c)) differs from male in having protibial spur, relatively smaller pronotum without armature, and in absence of inner protibial tooth. Body length 11.0–15.0 mm.
Variation
In addition to body size variability, males vary in the shape of the pronotum and its armature. In the material examined, there are specimens with a shallow excavation on pronotum medially and a small rounded anteromedial tubercle, and intermediate forms between it and specimens with fully developed pronotal armature.
Distribution
The distribution range of this species needs clarification. The specimens with exact locality data originated from Caracas,
Venezuela
. Most of the specimens, however, bear the label ‘Colombia’ or no locality label (
Figure 2
(g)). The record from
Chile
is doubtful.
Remarks
Paulian (1984)
described
Ae.
elongatum
based on the punctation of the mesepimera and elytra but he did not dissect the genitalia of the
holotype
. The characters of the punctation of the underside of the body vary and are largely not diagnostic. We dissected the aedeagus of the
holotype
and found that it has the characteristic shape of the parameres and endophallic hooks as in
Ae.
columbianum
(
Figures 2
(a,b,d–f) and 3 (a–c)). The other characters also agree with the latter species, and we therefore propose the new synonymy.
Almost all the material of
Ae.
columbianum
available to us was apparently collected in the nineteenth century. Only a few specimens were collected in the beginning of the twentieth century, and no recent records of this species are available.