Coridius insperatus Boyane, Ghate & Priyadarsanan, 2024

Boyane, Swapnil S., Sen, Sandeep, Priyadarsanan, Dharma Rajan, Thunga, Pavan Kumar, Joshi, Nikhil U. & Ghate, Hemant V., 2024, Integrative taxonomy of the genus Coridius Illiger, 1807 (Hemiptera: Heteroptera: Dinidoridae) reveals hidden diversity and three new species from North-East India, PLoS ONE (e 0298176) 1807 (7), pp. 1-46 : 11-15

Coridius insperatus Boyane, Ghate & Priyadarsanan , sp. nov. urn:lsid:zoobank.org: act:69C0D1FA-D2E0-4CD6-A1B3 9CAEE189EA15 ( Figs 5A, 6A, 9A, 10A, 11A and 12A).

Etymology. The species name is the Latin adjective insperatus (meaning ‘unexpected’ in Latin) because it is an unexpected member of the genus Coridius with four segmented antennae.

Material examined: Holotype male. INDIA: Arunachal Pradesh, Nirjuli , leg. Anil Talang, 1. i.2019, 27.128˚N, 93.742˚E, 139 m.

Paratypes. Same collecting data as holotype: 1 F. — INDIA: Arunachal Pradesh, Tippi , leg. Thejavikho Chase, 30.xi.2020, 27.026˚N, 92.610˚E, 179 m: 1 F. — INDIA: Arunachal Pradesh, Tutting , leg. Gumnya Ete, 13.xii.2019, 28.982˚N, 94.905˚E, 485 m: 1 F.— INDIA Arunachal Pradesh, Yingkiong , leg. Gumnya Ete, 12.xii.2019, 28.635˚N, 95.024˚E, 275 m: 1M.

Diagnosis. Overall colour yellowish brown. Pronotum ventrally pale yellowish brown, lateral margins black. Legs yellowish brown, femora slightly darker. Antennae with first segment basally ochraceous, distally dark brown, second and third black, fourth ochraceous except a minute region at base and apex which are black. Pronotum with a levigate pale line from posterior region of calli to posterior pronotal margin ( Fig 5A). Spiracles black, encircled by a pale ring.

Description. Overall structure, Body finely punctate; pronotum with a few transverse rugae in posterior two thirds; region around calli smooth, shining, with sparse punctures. Scutellum rugulose punctate in basal two third, apical region granulated. Prosternum with a distinct elevated smooth region on either side of median groove, laterally rugulose and coarsely punctate. Meso- and meta-sterna smooth medially, rugulose and coarsely punctate in pleural regions. Body nearly smooth medially on abdominal sternites, very finely punctate laterally. Legs laterally compressed; tibiae distinctly sulcate and spinose dorsally and ventrally, more compressed than femora; femora with ventral spines; first segment of tarsus densely setose, second and third with very sparse, long setae; claws widely separated, dark brown to black in distal half; pulvilli distinct, well developed ( Figs 5A and 6A).

Head transverse, two times wider than longer at eyes, mandibular plates much longer than clypeus, parallel sided, rounded anteriorly and reaching in front of clypeus ( Fig 9A). Dorsal surface of mandibular plates with irregular folds and scattered punctures. Vertex coarsely punctate medially, with longitudinal rugae and grooves near eyes. Eyes large, globular and pedunculate. Ocelli well developed, slightly elevated. Interocellar distance 1.51 times distance between eyes and ocelli. Antennae four segmented, first segment cylindrical with few setae, surpassing apex of head, second and third distinctly laterally compressed, second segment with many setae and longitudinal grooves in basal one fourth with fine spine like setae on the sides, third segment finely rugulose, with spine-like setae on both sides, slightly dilated in basal half while fourth segment rounded, gradually tapering, finely punctate and covered with numerous small and sparse, long setae.

Labium four segmented, reaching middle of meso-sternum; first and second segments sub-equal, third (0.81 mm) and fourth (0.64 mm) smaller. Bucculae prominent, raised above the level of labium.

Pronotum rugulose punctate, calli less punctate, somewhat shining. Anterior margin of pronotum concave behind head, slightly truncate medially behind eyes. width at anterior angles of pronotum only slightly wider than width at eyes. Lateral margins straight, slightly raised. Humeral angles rounded, posterior margin straight. Prosternum deeply sulcate in middle, its sides distinctly raised. Posterior margin of pro-sternum slightly sinuate in lateral parts. Pro-coxal area distinctly raised, pleural area coarsely punctate and rugulose, closer to coxae. Mesosternum smooth medially with shallow groove in anterior three fourth and slightly deeper groove in distal one fourth, especially near meso coxae. Pleural area coarsely punctate and rugulose. Metasternum very narrow between coxae, metasternum not covering spiracle of first visible abdominal segment posteriorly, leaving it partly exposed.

Scutellum triangular, median region elevated, lateral margins distinctly sinuate in the middle, apical region broadly rounded. Apical area finely punctate and rugulose, with coarse punctures. Median levigate line in basal half continuing pronotal levigate line.

Hemelytra. Clavus narrow, short, corium very broad, very finely and closely punctate and rugulose, punctures at margins slightly coarse. Membrane long and broad with numerous longitudinal veins and three basal cells. Hemelytra longer than abdomen. Extreme basal region of corium upturned forming shallow groove, its margin black, similar to that of pronotum, remaining margin of corium flat.

Abdomen broad, with sinuate intersegmental sutures sinuate, seventh sternum longest. Spiracles situated closer to anterior margin than to lateral margin of segment. Trichobothria distinct, a pair situated posteriorly to pseudosuture, which is posterior to spiracle.

Male genitalia. Pygophore 0.91 times wider than long, somewhat rectangular, and sclerotized. Basally convex, flat in distal half, ventral surface rugulose and ventral margin with fine black denticulation, with sparse setae. Ventral rim with rugae and numerous long ochraceous setae ( Fig 10A), ventrally convex and smooth ( Fig 11A). Parameres sclerotized, short, medially rounded and apically narrowing, apical tip with rugae and setae ( Fig 12A).

Geographical distribution. Presently known only from Arunachal Pradesh, India.

Remarks. Coridius insperatus sp. nov., is a very distinct species compared to other congeneric species. It can be easily distinguished by its four segmented antennae and cupreous dorsal colouration, while all other species in the genus are dark brown, yellow to black dorsally, and have five segmented antennae. In the family Dinidoridae , the genus Amberiana Distant, 1911 , has one species with four segmented antennae ( A. major Schouteden, 1912 ), while other species ( A. montana Distant, 1911 ) have five segmented antennae [ 23, 24].

This species is edible and consumed by the Nyishi and Adi tribes of Arunachal Pradesh. In addition, we found that this species is sold in the Nirjuli local market (Dist. Itanagar, Arunachal Pradesh) during the winter season (October–January).