Laccobius (Glyptolaccobius) shorti, Gentili, 2006

Gentili, Elio, 2006, Revisional notes on the genus Laccobius. I. Subgenus Glyptolaccobius (Coleoptera: Hydrophilidae), Acta Entomologica Musei Nationalis Pragae 46, pp. 57-76 : 71-72

Laccobius (Glyptolaccobius) shorti sp. nov.

( Figs. 36-38 )

Type locality. Thailand, Kanchanaburi Prov., Amphur Tong Pha Phum, 500 m a.s.l.

Type material. HOLOTYPE: J, 1.7 × 1.1 mm ( NMNH): ‘ THAILAND, Kanchanaburi Prov. / Amphur Tong Pha Phum; small / waterfall 6.3 km W of Border Police / Stn. at Ban Padsadoo Klang , 500 m / 14°32′N 98°32′E; 10 April 2003 / UMC & CMU teams; L-463 // [red label] HOLOTYPUS J / Lacc. shorti m. / E. Gentili 2006’. PARATYPES: 7 JJ 11 ♀♀ 3 spec.: same locality as holotype ; ‘ Chiang Mai Prov., Doi Inthanon N. Park, 1060 m, Huai Sai Lueung WF, 18°31′N 98°27′E ; R.W. Sites 20.03.2002 ’, 1 J ; ‘ Chiang Mai Prov., Doi Inthanon N. Park, 1379 m Pha Dum Waterfall , rock face 18°36′N 98°31′E ; 3.5.2003 UMC-CMU teams coll.’, 2 JJ 3 ♀♀; ‘ Chiang Mai Prov., Doi Inthanon N. Park, Siritharn Waterfall, 18°32′N 98°34′E 829 m ; 2.5.2003; l-497; colls. UMC & CMU teams’, 2 ♀♀; ‘ Chiang Mai Prov., Doi Suthep-Pui Natl. Pk. Namtok Monthathan 700 m L-489 18°49′N 98°55′E 29.4.2003 AV, Thamasenanupap, Ferro’, 3 JJ 7 ♀♀ ; ‘ Chiang Mai Prov., Doi Suthep-Pui Natl. Pk., Huai Kaew at Monthanatharn 18°49′N 98°55′E, 17.5.2001 G.W. Courtney’, 1 ♀ (all these paratypes in ASCI, MSNV) .

Description. Total length 1.7-2.0 mm, total width 1.1-1.3 mm (holotype 1.7 × 1.1 mm). Body wide oval, feebly convex, widest in anterior third.

Head. Coloration entirely black, impunctate or with rare and faint punctures, without any trace of frontoclypeal suture and without microsculpture. Labrum black, anterior margin straight, slightly notched medially. Periocular groove and ‘systematic punctures’ indistinct. Eyes oblong, oblique, closest to each other anteriorly, not protruding; postocular portion of tempora small; maximum eye diameter nearly equal to interocular space in frontal view. Prementum with long black setae. Mentum trapezoid, microgranulate, nearly in one plane. Submentum and gula smooth and shining, with sparse large punctures. Gular sutures converging posteriorly. Maxillary palpi yellow-brown; palpomere 1 thin and short, palpomeres 2 and 3 nearly equal in length, dilated at apex, palpomere 4 elongate, nearly twice as long as palpomere 3, asymmetrical, outer margin straight and inner margin convex. Eight antennomeres.

Thorax. Pronotum transverse, 0.42 times as long as wide, black with yellowish-brown lateral margins, the latter wider posteriorly; smooth as head, without microsculpture, except some sparse and faint punctures. Prosternum black, with longitudinal keel. Scutellar shield equilateral, black, without punctures. Mesoventrite with simple longitudinal keel. Elytra ca 0.9 times as long as wide, black with yellowish-brown margins and apex; with 10 longitudinal rows of setiferous, more impressed punctures alternating with 10 rows (interstriae) of more sparse and fainter punctures; parasutural furrow covering nearly posterior two thirds of elytra. Epipleura black, nearly horizontal. Pseudepipleura yellowish, nearly vertical, wider than epipleura. Metaventrite setiferous with median longitudinal glabrous area posteriorly.

Legs. Fore coxae granulate; fore femora granulate and setiferous on basal half, smooth distally, with tibial groove; fore tibiae smooth, without longitudinal grooves. Middle femora with tibial grooves; ventral side of middle tibiae with sulcus between two longitudinal ridges. Hind trochanters smooth and shining; hind femora with scarce punctures and tibial grooves; hind tibiae curved, ventral side with longitudinal sulcus between two ridges.

Abdomen. Ventrites 1-6 smooth, with lateral setae.

Male genitalia. Aedeagus ( Figs. 36-38 ) nearly 0.25 times as long as body; parameres nearly as long as phallobase; apex of median lobe nearly at level of apex of parameres.

Differential diagnosis. Laccobius shorti sp. nov. belongs to the group of species with longitudinal rows of elytral punctures and curved hind tibiae. It differs from L. celsus , L. munus , and L. sharmai by the small size and uniformly dark elytral surface (excluding lateral borders and apex) without longitudinal furrows but with long setae on the punctures of the primary rows. Apical portion of parameres is neither swollen (in contrast to L. celsus ) nor excised medially (in contrast to L. munus ) nor slightly concave externally (in contrast to L. sharmai ). It differs from L. silvester sp. nov. by having a comparatively broader aedeagus with parameres as long as the basal segment (parameres longer than the basal segment in L. silvester sp. nov.).

Etymology. It is a great pleasure to dedicate this new species to Andrew Short, a specialist in the Hydrophilidae .

Distribution. Thailand.

Figures

Figs. 30-38. 30-31 – Laccobius senguptai Gentili, 1979, holotype. 30 – aedeagus, dorsal view; 31 – ditto, lateral view. 32-33 – L. sharmai Gentili, 1995, holotype. 32 – aedeagus, dorsal view; 33 – ditto, lateral view. 34-35 – L. silvester sp. nov., holotype. 34 – aedeagus, dorsal view; 35 – ditto, lateral view. 36-38 – L. shorti sp. nov. 36 – holotype, aedeagus, dorsal view; 37 – paratype from Chiang Mai, aedeagus, lateral view; 38 – holotype, ventral view.