Laccobius (Glyptolaccobius) hanka, Gentili & Fikaček, 2009

Gentili, Elio & Fikaček, Martin, 2009, Taxonomic notes on Laccobius, subgenus Glyptolaccobius, with new records and description of four new species (Coleoptera: Hydrophilidae), Acta Entomologica Musei Nationalis Pragae 49 (2), pp. 607-623 : 612-614

Laccobius (Glyptolaccobius) hanka sp. nov.

( Figs. 2 )

Type locality. India, Arunachal Pradesh, 1 km N of Bhalukpong, 27°01′21″N 92°38′06″E, 240 m a.s.l.

Type material. HOLOTYPE: J ( NMPC): ‘INDIA, Arunachal Pradesh (16a) / 1 km N of Bhalukpong / 7–8.V. 2008, 240 m / 27°01′21″N 92°38′06″E / Fikáček, Podskalská, Šípek lgt. // seepage: wet rock with moos [= moss] / and Nostoc below steep slope / with tropical evergreen forest’ . PARATYPES: INDIA: ARUNACHAL PRADESH: same data as holotype, 26 spec. ( KSEM, MSNV, NMPC).

Description. Total length 1.45–1.85 mm (holotype: 1.60 mm), total width 0.90–1.10 mm (holotype: 1.00 mm). Body widely oval, convex, maximum length / maximum width ratio 1.6; maximum width between anterior elytral third and elytral midlength.

Head. Coloration shining black, with rare and faint punctures, surface smooth without microsculpture; ‘systematic punctures’ indistinct; anterolateral branches of frontoclypeal suture conspicuous at 100×. Labrum black, trapezoid, without specula; anterior margin nearly straight, slightly emarginated medially; lateral margins oblique, posterior margin straight. Eyes oblong, oblique, closest to each other posteriorly, not protruding laterad, separated by distance equal to 2.5× of one eye; postocular portion of tempora short. Mentum flat or slightly convex, smooth without punctures, emarginated anteriorly. Submentum and gula smooth. Maxillary palpi yellowish; palpomere 1 thin and short; palpomeres 2 and 3 nearly equal in length, both dilated at apex; palpomere 4 elongate, nearly twice as long as palpomere 3, symmetrical, inner and outer margin convex, apex truncate. Eight antennomeres; scape longer than antennomeres 2–4 combined; pedicel cone-shaped; intermediate antennomeres (antennomeres 3–4) very short; cupule asymmetrical, oval in ventral view, crescent-shaped and emarginate in dorsal view; antennal club loose, with densely arranged setae, antennomeres 6 and 8 nearly equal in length, antennomere 6 wider, antennomere 7 shorter and narrower.

Thorax. Pronotum transverse, 0.38× as long as wide, widest at posterior margin; blackish with yellowish, posteriorly widened lateral margins, yellow space reaching width of eye; surface smooth, without microsculpture. Prosternum black, with longitudinal keel. Scutellar shield equilateral, dark, impunctate. Mesoventrite with longitudinal keel, tuberculate anteriorly. Elytra combined ca 1.15× as long as wide; brown to black with yellowish lateral margins and apices; each elytron with indistinct pale yellow dot at base; 10 longitudinal rows of larger setiferous punctures alternating with 10 rows (interstriae) of sparser and fainter punctures; all rows less conspicuous in darker specimens. Black parasutural space forming a flat and shining stripe extended over parasutural furrow. Epipleura and pseudoepipleura oblique, nearly vertical. Metaventrite setiferous with three postero-median, posteriorly converging sulci.

Legs. Fore coxae and trochanters granulate, pubescent; fore femora setiferous on basal third, smooth distally, with tibial groove; fore tibiae smooth, each with stiff setae and two apical spurs. Middle femora with tibial grooves; ventral side of each middle tibia with three longitudinal rows of stiff setae and sulcus between two longitudinal ridges. Hind trochanters smooth and shining; hind femora smooth, with setiferous punctures and tibial grooves; hind tibiae curved, ventral side of each tibia with three longitudinal rows of stiff setae and longitudinal sulcus between two ridges.

Abdomen. Ventrite 1 granulated, ventrites 2–4 smooth, ventrites 5–6 granulated with short setae.

Aedeagus ( Fig. 3 ): Total length 0.37–0.49 mm. Parameres nearly as long as phallobase; medial margin of parameres subparallel, apices slightly diverging in dorsal view. Median lobe wide, tongue-shaped, slightly constricted at midlength, barely rounded apically, nearly as long as parameres.

Differential diagnosis. Laccobius hanka sp. nov. belongs to a group of Glyptolaccobius species with curved hind tibiae and pubescent elytra with longitudinal rows of punctures (together with L. silvester , L. shorti and L. sipeki sp. nov.). It differs from all three mentioned species by the pale spot on the elytral base and the wide median lobe.

Etymology. The new species is named after Hanka, a diminutive of the first name of Hana Šípková (her maiden name was H. Podskalská), who collected part of the type series of this species. To be treated as a noun in apposition.

Bionomics. All specimens were collected at a seepage site at a roadside below a steep slope covered with moss and a mat of Nostoc ( Fig. 13 ). The locality is situated at the margin of the Assam Valley where the first highlands of the Himalaya Range begin to rise.

Distribution. India, lowland border regions of Arunachal Pradesh. So far known only from the type locality.

Figures

Figs. 1–3. Aedeagus (a – ventral view, b – dorsal view, c – lateral view). 1 – L. guttalis sp. nov.; 2 – L. hanka sp. nov.; 3 – L. josefi sp. nov. Scale bar: 0.25 mm.

Figs. 11–13. Habitats of Glyptolaccobius species.11 – India, Meghalaya, Laitkynsew env., 460 m a.s.l.: type locality of L. sipeki sp. nov., locality of L. pluvialis and L. eliogentilii (arrow indicates the position of the microhabitat where the specimens were collected); 12 – India, Meghalaya, Laitkynsew env., 810 m a.s.l.: exposed seepages at the side of a road, locality with common occurrence of L. pluvialis; 13 – India, Arunachal Pradesh, 1 km N of Bhalukpong: seepages at the road side, type locality of L. hanka sp. nov. and L. josefi sp. nov. Photos by M. Fikáček.