Pseudolathra unicolor ( KRAATZ , 1859)

Assing, V., 2012, The Pseudolathra species of the East Palaearctic and the Oriental regions (Coleoptera: Staphylinidae: Paederinae), Beiträge Zur Entomologie = Contributions to Entomology 62, pp. 299-330 : 305-308

Pseudolathra unicolor ( KRAATZ, 1859) ( Figs 1-10 , Map 1 )

Lathrobium unicolor Kraatz, 1859: 117 .

Lathrobium testaceum Motschulsky, 1858: 646 f.; preoccupied.

Lathrobium pallens Gemminger & Harold, 1868: 611 ; replacement name.

Lathrobium chujoi Last, 1966: 5 f.; syn. n.

Type material examined:

L. unicolor : Lectotype ♂ [dissected prior to present study; somewhat damaged], present designation: “ India orient. / Coll. Kraatz / Coll. DEI Eberswalde / Syntypus / Pseudolathra unicolor (Kr.) ♂, V.I. Gusarov det. 1994 / DEI Müncheberg, Col - 02775 / Lectotypus ♂ Lathrobium unicolor Kraatz , desig. V. Assing 2012 / Pseudolathra unicolor (Kraatz) , det. V. Assing 2012” ( SDEI) . Paralectotypes: 2 ♀♀: same data as lectotype ( SDEI) ; 1 ♀: same data, but “ India or., Bacon leg.” ( SDEI) .

L. chujoi : Paratypes: 1 ♂, 2 exs.: “ Manchester Museum Paratype / F8008.5327-29 / Lathrobium chûjôi sp. n., Paratype, H. Last det. / Pseudolathra unicolor ( Kraatz) , det. V. Assing 2012” ( MMUM) .

Comment:

The - extremely short - original description of Lathrobium unicolor is based on an unspecified number of syntypes from “ India orientale, praecipue boreali” collected by “Dom. Bacon” ( Kraatz 1859). Four syntypes, one male and three females, were located in the Kraatz collection at the SDEI. They had lectotype and paralectotype labels by V. Gusarov attached to them, but since a lectotype designation had not been published, these labels were removed to avoid confusion. The male is here designated as the lectotype; its aedeagus is illustrated in Figs 1-2 .

Lathrobium testaceum was described from an unspecified number of syntypes from “Indes orientales” ( Motschulsky 1858). This name is a junior primary homonym and was subsequently replaced with L. pallens by Gemminger & Harold (1868). Lathrobium pallens and L. testaceum have been treated as synonyms of L. unicolor at least since Fauvel (1904).

In the original description of L. chujoi , which is based on a “ Type, ♀ ” [sic] and eleven paratypes from “ Thailand: Nakon Sawan ( Last 1966), there is no reference whatsoever to Pseudolathra unicolor . An examination of three paratypes revealed that they are conspecific with P. unicolor , hence the synonymy proposed above. The aedeagus of a male paratype is illustrated in Figs 5-6 .

Additional material examined:

Nepal: 7 exs., Narayani, Chitwan, Gynganagar , at light, 9.V.2005, leg. Ahrens ( NME, cAss) ; 1 ♀, Chitwan National Park, Sauraha , ca. 200 m, at MV light, 4.VI.1983, leg. Brendell ( BMNH) .

India: 13 exs., Assam, Kaziranga Wildlife, Pan Bari Reserve Forest , 26°45'N, 93°10'E, 100 m, 12-21.XI.1997, leg. Siniaev & Murzin (cSch, cAss) ; 4♀♀, Assam, Bhalukpong , 27°02'N, 92°35'E, 150 m, 26.V.-3.VI.2006, leg. Dembický & Pacholátko ( BMNH, cAss) ; 1 ♂, Assam, Umrongso env., 25°27'N, 92°43'E, 700 m, 3-8.VI.2002, leg. Trýzna & Benda (cSch) ; 1 ♀, West Bengal, Darjeeling distr., Kalimpong, Dumra Busty , 1000 m, 12.VIII.1990, leg. Dangal (cKle) ; 1♀, 2 exs. without abdomen, Calcutta ( BMNH) ; 1 ♀, Calcutta , 26.X.1949, leg. Kapur ( BMNH) ; 1 ♀, Arunachal Pradesh, 8 km S Jamiri, near Sessa , 27°07-09'N, 92°34'E, 350 m, 26.V.-4.VI.2005, leg. Dembický ( BMNH) ; 1♀, Uttar Pradesh, Kheri Forest [25°21'N, 79°17'E], II.1916, leg. Champion ( BMNH) ; 1♀, Bihar, Pusa [25°58'N, 85°40'E], 15.V.1931, leg. Fletcher ( BMNH) .

Myanmar: 5 exs., Pegu, 60 km NW Yangon, 17°19'N, 96°28'E, light trap, 22.XI.2003, leg. Hornburg (cSch, cAss) ; 1♂, 2 ♀♀, Tharrawaddy, leg. Corbett, Andrewes, etc. ( BMNH) ; 1 ♀, locality not specified ( BMNH) .

Bangladesh: 1 ♂, Dhaka [“ Dacca ”] ( BMNH) .

China: 1 ex., Yunnan, Dali Bai Aut. Pref., 5 km SSW Dacang , water reservoir, 25°24'N, 100°12'E, 1780 m, bank of reservoir, 17.IX.2009, leg. Wrase (cAss) .

Thailand: 1 ♀, 25 km NW Lan Sak, X.1989, leg. Thielen (cAss) ; 2 ♀♀, Kanchanaburi, farmland near Kwai river, 400 m, 25.-27.III.1987, leg. Brendell ( BMNH). Locality not identified : 1 ♀, Shuregu [?], leg. Champion ( BMNH) .

Redescription:

Body length 5-6 mm; length of forebody 2.7-3.0 mm. Coloration variable: body either uniformly reddish or partly (head, postero-lateral portion of elytra, abdominal segments III-VI) more or less distinctly infuscate; legs yellowish to reddish-yellow; antennae reddish.

Head approximately as broad as long or weakly transverse; punctation coarse and sparse, in median dorsal portion very sparse or absent; interstices without microsculpture and glossy. Eyes large, but of variable size, usually somewhat longer, rarely shorter than postocular region in dorsal view. Antennae slender, 1.8-2.0 mm long; all antennomeres oblong.

Pronotum of somewhat variable shape, 1.1-1.2 times as long as broad and approximately 1.1 times as broad as head; on either side of the impunctate midline with series of 15-20 punctures, these punctures often accompanied by additional punctures; punctation of lateral portions sparse to moderately dense; interstices without microsculpture.

Elytra approximately as long as pronotum or slightly longer; laterally with fine and almost complete submarginal carina; punctation arranged in more or less pronounced series; interstices without microsculpture. Hind wings fully developed.

Abdomen slightly narrower than elytra; punctation very fine and very dense; interstices with microsculpture; posterior margin of tergite VII with palisade fringe.

♂: protarsomeres I-IV strongly dilated; sternite VII without distinctly modified pubescence and shallow median impression, posterior margin broadly concave ( Fig. 9 ); sternite VIII oblong, posterior excision narrow and deep, not quite reaching middle of sternite ( Fig. 10 ); aedeagus 1.15-1.30 mm long, shaped as in Figs 1-8 .

♀: protarsomeres I-IV distinctly dilated, but slightly less so than in male.

Intraspecific variation:

This species is highly variable, particularly in coloration, density of punctation, eye size, shape of head and pronotum, to some extent also in the size of the aedeagus. In material from India, the body is usually of uniformly reddish coloration, whereas in specimens seen from Myanmar and China the head and the postero-lateral portion of the elytra are often more or less distinctly infuscate; occasionally the head may even be black. In most specimens the eyes are large, bulging, and longer than the postocular region; in the male from China, however, they are less convex and shorter than the postocular region. The variation of the aedeagus is illustrated in Figs 1-8 .

Distribution and natural history:

The species is evidently widespread in the southern East Palaearctic and Oriental regions. Malebased records have been seen from Nepal, North India, Myanmar, Bangladesh, China, and Thailand ( Map 1 ). Owing to possible confusion with externally similar species ( P. himalayana , P. villiersi , etc.), all previous records and all the female-based records listed above should be considered doubtful.

On at least two occasions, P. unicolor was collected at light traps in May and November. In one locality in southern central Nepal, the species was found together with P. himalayana and P. pulchella . One specimen from China was taken on the shore of a reservoir.

Figures

Map 1: Distributions of Pseudolathra unicolor (triangles; open triangles: female-based records), P. tichomirovae (open squares), P. lineata (filled squares), P. cordiformis (filled diamond), and P. brevincisa (open circle), based on revised records.

Figs 1-10: Pseudolathra unicolor; lectotype of P. unicolor (1-2), paratype of P. chujoi (5-6), and males from Assam (3-4) and Yunnan (7-10): aedeagus in lateral and in ventral view (1-8); male sternite VII (9); male sternite VIII (10). Scale bars: 0.5 mm.