Taxonomy of the dung beetle genus Ochicanthon Vaz-de-Mello (Coleoptera: Scarabaeidae: Scarabaeinae) of the Indian subcontinent, with notes on distribution patterns and flightlessness
Author
Latha, Mathews
Author
Cuccodoro, Giulio
Author
Sabu, Thomas K.
text
Zootaxa
2011
2745
1
29
journal article
10.5281/zenodo.276621
a6eb9c5a-9b0b-47df-a207-6c5ee54acebd
1175-5326
276621
Ochicanthon laetus
(Arrow)
(
Figs. 26–30
)
Phacosoma laetum
Arrow, 1931
: 356
.
Description.
Body (
Fig. 26
) predominantly black with distinct orange-yellow humeral spot on each elytron. Punctation on dorsal surface of head annular separated by intervals of nearly their diameter. Pronotum in lateral view weakly convex, outline at base almost in line with that of elytral suture; laterobasal paramarginal ridge well marked, extended on slightly more than one third of pronotal length. Pronotal punctation (
Fig. 27
) consisting of annular setiferous punctures separated by interval of approximately their diameter, becoming finer anteromedially; setae almost indistinct, straight and recumbent. Elytra in lateral view weakly convex; suture not raised; striae shallow, wide, consisting of chains of fairly confluent discoidal depressions (
Fig. 27
); interstriae weakly convex, uneven, finely punctate, irregularly; background microsculpture smooth; setae fine, recumbent and straight; lateral ridge posteriorly extended nearly to level of apex of third stria. Mesosternum punctate along the base; mesometasternal line subangulate in middle; metasternum coarsely punctate except the centre which is almost smooth (
Fig. 28
). Pygidium covered with annular setiferous punctures becoming finer ventrally. Protrochanter with outer margin arcuate.
Hind
wings present.
Male lacking obvious secondary sexual characters. Aedeagus as in
Figs. 29–30
.
Measurements
(mm, n=4): TL = 4.1–4.5; BW = 2.5–2.8; PL = 1.1–1.2; PW =2.2– 2.4; EL = 2.1–2.3.
Material examined.
Holotype
(female,
BMNH
): “Nilgiri Hills, H.L. Andrews [printed] / Andrewes Bequest B.M.1922-331 [printed] /
Phacosoma laetum
type
arr. [handwritten by Arrow] /
Phaccosoma laetum
Arrow
[handwritten by Bacchus] M.E. Bacchus det 1975”.
Paratypes
(3,
BMNH
) “Nilgiri Hills H.L. Andrews [printed] / Andrewes Bequest B.M.1922-331 [printed] /
Phacosoma laetum
Arrow
[handwritten by Bacchus] M.E. Bacchus det 1975”,
1 male
; “Nilgiri Hills H.L. Andrews [printed] / H.L. Andrews Nilgiri Hills [printed] / 363 [handwritten] / Andrewes Bequest B.M.1922-331 [printed] /
Phacosoma laetum
co-type Arr. [handwritten by Arrow] /
Phacosoma laetum
Arrow
[handwritten by Bacchus] M.E. Bacchus det 1975”,
1 male
; “Nilgiri Hills H.L. Andrews [printed] / H.L. Andrews Nilgiri Hills [printed] / Andrewes Bequest B.M.1922-331 [printed] /
Phacosoma laetum
co-type Arr. [handwritten by Arrow] /
Phacosoma laetum
Arrow
[handwritten by Bacchus] M.E. Bacchus det 1975”
1 female
.
Additionnal material (
1 male
,
MHNG
): “
India
, Kerala, Palghat Hills, [
10 km
N of] Malampuzha Dam,
150 m
,
27.xi.1972
, leg. Besuchet, Löbl & Mussard, #54” [sifting in
Hevea
plantation].
Distribution and natural history.
South
India
(Nilgiri Hills in the South Western Ghats montane evergreen forests ecoregions; Malampuzha, in the South Western Ghats moist deciduous forests ecoregion). The occurrence of this species in northeast
India
(Balthasar 1963: Bihar, Chota Nagpur) is very doubtful.
Diagnosis.
Ochicanthon laetus
is the only member of the genus to possess spotted elytra bearing elytral striae consisting of chains of fairly confluent discoidal depressions. It can be easily distinguished from
O. mussardi
and
O. nitidus
by its basally punctate mesosternum. See discussion under
O. mussardi
.