Calvia explanata sp. n. (Coleoptera: Coccinellidae: Coccinellinae) from the Indian Subcontinent

Abstract Calvia explanata sp. n. (Coleoptera: Coccinellidae), externally similar to and commonly misidentified as Calvia albida Bielawski, is described from India and Nepal.


Introduction
The genus Calvia Mulsant (1846) is distributed throughout the Palaearctic and Oriental regions and contains over 20 species. A single species, C. quatuordecimguttata (L.) occurs widely in the northern half of North America (Booth 1997). Booth (1997) reviewed the species of the genus from the Indian Subcontinent, most of them being endemic to the Himalayas, and provided a key to species along with biological notes. Accounts of some of these species with illustrations are also given by Yu (2010) and Ren et al. (2009). A species of Calvia externally very simillar to C. albida Bielawski (1972) and labelled as the latter was found in collections from northeastern India and Nepal and is described and illustrated here.

Materials and methods
For preparation of male and female genitalia, whole specimens were immersed in warm soapy water for 10 minutes. The abdomen was detached gently with a minuten pin and kept overnight in 10% KOH. The genitalia were dissected in distilled water and transferred to glycerol for studies and imaging. After examination, the genitalia were transferred to microvials and pinned beneath the respective specimens. The following measurements were made using the measurement module of a Leica M205A stereo microscope: total length, from apical margin of clypeus to apex of elytra (TL); total width, across both elytra at their widest point (TW = EW); pronotal length, from the middle of anterior margin to the base of pronotum (PL); pronotal width at its widest (PW); elytral length along suture from apex to base including scutellum (EL). Images of whole specimens and their diagnostic characters were taken using a Leica DFC 420 camera attached to a Leica M205A stereo microscope. Composite images were generated from image stacks using Combine ZP and touched up in Adobe Photoshop Elements 11. The specimens studied are deposited in the following collections: NBAII -National Bureau of Agriculturally Important Insects, Bangalore; NPC -National Pusa Collection, Indian Agricultural Research Institute, New Delhi.

Taxon treatment
Calvia explanata, sp. n.  (Fig. 1a, b, c) broadly oval, dorsum convex, broadest a little before middle of elytra, elytra nearly as wide as long; glabrous except head with silvery white hairs. Dorsum bright lemon yellow to yellowish green except lateral margins of pronotum and elytra transparent, pronotum with an indistinct M-shaped marking. Antennae, mouthparts and ventral side yellowish brown; ventral surface covered with short, silvery white pubescence. Head with clypeal margin truncate between lateral projections; eyes prominent, inner ocular margins anteriorly distinctly divergent. Antenna 11-segmented, elongate, >2× as long as interocular distance, with a moderately long 3-segmented club, terminal antennomere oval, apically flattened.
Female: Externally similar to male. Female genitalia (Fig. 2f) as shown, spermatheca bulky, sperm duct somewhat abruptly thickened a little after basal third; infundibulum present, composed of a pair of apparently lamellate structures.

Diagnosis
This species is externally similar to C. albida, C. flaveola Booth and C. championorum Booth. It is particularly close to C. albida (Fig. 1d) in having a mottled elytral pattern with several smaller spots. Both C. albida and C. explanata share a similar distribution range in India and are found in northeastern India and Nepal. Calvia albida is also distributed in China (Ren et al. 2009;Yu 2010). Calvia explanata differs from C. albida in having a distinctly wider, more circular body outline and explanate elytral margins. The male genitalia are also distinctive with the penis guide narrower and more elongate and the penis with an elongate, membranous apical process. In C. albida, the penis guide is distinctly broader up to a little beyond middle and the posterior half is much less narrowed and the penis has a more robust basal capsule and the apex is different. The male genitalia of C. albida were illustrated by Bielawski (1972) and Ren et al. (2009). The female genitalia in C. albida (Fig. 3) has a distinctly bulkier spermatheca ( Fig. 3b) with a long, more or less uniformly thick sperm duct and the infundibulum is differently structured.

Etymology
The specific epithet is an adjective of Latin origin and refers to the explanate elytral margins.

Biology
This species seems to have an arboreal habitat like many other species of Calvia (Booth 1997) as some of the specimens examined were collected on Alnus sp. (label data).

Taxon discussion
Calvia is not a very well defined genus with some members having aberrant characters. This species is placed in Calvia by the following combination of characters as per the diagnosis given by Gordon (1985): anterolateral angles of clypeus produced forward, lateral margins of pronotum and elytra explanate, middle and hind tibial apices with a pair of spurs each, abdominal postcoxal line incomplete, and tarsal claws appendiculate. Gordon (1985) in his diagnosis of Calvia mentioned that female genitalia lack infundibulum, but female genitalia of many Oriental species of Calvia, including C. explanata, have a distinct infundibulum.