Oenopia excellens (Crotch) Crotch, 2005

Poorani, J. & Booth, R. G., 2005, On the identity of Dysis excellens Crotch (Coleoptera: Coccinellidae: Coccinellini), a little known Oriental lady beetle, Zootaxa 875, pp. 1-5 : 2-4

Oenopia excellens (Crotch) , comb. nov. ( Figs. 1–4 )

Dysis excellens Crotch, 1874: 160 (Syntype Ψ, BMNH; Type locality: “ Cochin China ”). Dysis excellens: Korschefsky, 1932: 298 .—Gordon, 1985: 20.

Description. Length: 2.88–3.06 mm, breadth: 2.52 mm. Female: Form ( Fig. 1 A) oval, about 1.2 x as long as broad, convex, head with few long hairs just below clypeal margin and on either side of eyes. Head black, antennae and mouthparts yellowish to pitchy brown. Pronotum black, sides and anterolateral corners white when alive, turning luteous to yellow when dead. Scutellum black. Elytra black with four reddish­orange or yellow spots arranged in two rows, one in either half of elytra, anterior pair large and transverse, posterior pair more or less oval and much smaller. Ventral side with pronotal hypomera and mesosternal epimera whitish to luteous yellow, legs dark brown except femoral apices, tibiae, and tarsi much lighter brown, rest of ventral side more or less completely dark pitchy brown.

Head sparsely punctate, interspaces between punctures with reticulate microsculpture. Pronotum evenly punctate, interspaces between punctures smooth and shiny. Elytra with punctation denser and deeper than that on pronotum, interspaces between punctures with conspicuous, deep microsculpture.

Prosternal intercoxal process with paired carinae, anteriorly slightly divergent. Anterior margin of mesosternum medially shallowly emarginate. Postcoxal line on abdominal sternite I incomplete, without a clearly demarcated associate line. Apical border of fifth abdominal sternite truncate, of sixth evenly arcuate. Spermatheca ( Fig. 2 ) with ramus and cornu together very long and S­shaped, ramus very elongate and gooseneck­shaped, distally swollen and bulbous; infundibulum bell­shaped.

Male: Body outline ( Fig. 1 B) subcircular, more rounded than that of female. Head yellow, pronotum and elytra dark pitchy brown to black, with similar pattern as in female. Ventral side with pronotal hypomera, mesosternal epimera, and anterior inner half of elytral epipleura yellow, legs lighter, uniform yellowish brown. Pronotum with interspaces between punctures clearly microreticulate. Elytral punctation similar to that in female.

Apical border of fifth abdominal sternite deeply and semicircularly emarginate, of sixth briefly and shallowly emarginate. Genitalia ( Figs. 3–4 ) as illustrated.

Specimens examined: Five. Lectotype Ψ (here designated) Type [circular label with red border]/ 25489 [Fry catalogue number]/ Mouhot [?collector’s name]/ Camboja / excellens n. sp. [Crotch’s handwriting]/ Type / Fry coll. 1905­100 (BMNH)/ Lectotype Dysis excellens Crotch des. J. Poorani & R.G. Booth 2005. Lectotype designation. India: Nagaland: Piphema, 1.vii.82, S. Sharma, ICAR, rice, 1Ψ (BMNH); Nagaland: Medziphema, 25.xi.2004, N.S.Rao, resting on Psidium guajava , 1Ψ; 10.iv.2004, H.K. Singh, collected on citrus, 1ɗ; 21.3.2004, H.K. Singh, in netsweeps from rice, 1Ψ (PDBC).

Distribution: Vietnam /? Cambodia (“ Cochin China ”); India (presently known from Nagaland).

Host data: The specimens examined were collected on citrus, guava, and rice.

Remarks: This species is transferred to Oenopia on account of the following characters: (i) short antenna, only slightly longer than frons, (ii) parallel innerocular margins, (iii) shallowly emarginate anterior margin of mesosternum, and (iv) the male and female genitalia, which are more or less characteristic across the genus.

Although Crotch (1874) gave the locality data of this species as Cochin China, nowadays Vietnam, the specimen locality label indicated Camboja (presumably Cambodia). This is the first record of this species from India.

This species is remarkably similar in external appearance and coloration to Oenopia guttata ( Blackburn, 1892) found in Australia, New Guinea, and the Philippines. The specimens examined were slightly smaller in size than the range specified for O. guttata by Pope (1989). The front pair of elytral spots in the lectotype of O. excellens is closer together than in O. guttata and there are very slight differences in the strength of punctation.

However, the male genitalia and female spermatheca are diagnostic and very distinctly different from the illustrations provided by Bielawski (1964) and Pope (1989), in the following ways. The apical emargination of the median lobe of the tegmen is deep and parabolic in O. excellens , but shallower and broadly U­shaped in O. guttata . The parameres appear to be shorter than the median lobe in O. excellens , but are comparatively longer in O. guttata . The ramus of the female spermatheca is very long and gooseneck­shaped in O. excellens , but much shorter and straight in O. guttata . Further, the cornu is semicircular and strongly curved in O. excellens , but much shorter, wider and very shallowly arcuate in O. guttata .

This species belongs to the Gyrocaria group of the genus that are characterized by a more or less convex, circular to oval body outline and other genitalic differences indicated by Vandenberg (1999).

Figures

FIGURES 1 – 4. Oenopia excellens (Crotch): 1 A. Female, dorsal habitus; 1 B. Male, dorsal habitus; 2. Female spermatheca; 3 – 4. Male genitalia: 3. Tegmen, ventral view; 4. Sipho.