Lagaroceras tulense, Nartshuk, E. P., 2013

Nartshuk, E. P., 2013, Grassflies of the subfamily Chloropinae (Diptera: Chloropidae) from Vietnam and Thailand, with descriptions of two new species, Zootaxa 3702 (6), pp. 534-544 : 539

Genus Lagaroceras Becker, 1903

The genus is distributed in the Afrotropical, Oriental and southern part of Palaearctic Regions, and in Australia. Up to now 18 species were described, and a species is added in this paper. According to Deeming (2011) the larvae develop in grass shoots. Lagaroceras tenuicorne Malloch was reared from larvae boring in shoots of Chloris barbata Sw. ( Malloch, 1927b) .

Lagaroceras tulense sp. n. ( Fig.9, 11–13 ).

Type material. Holotype male– Vietnam: Pr. Ha Son Binh, Da Bac, Tuly, 21.10.1990 (Nartshuk). Paratypes: 4 ♀from Vietnam with the same label as holotype.

Thailand: Chaiyaphum, Tat Tone NP, Near stream, 15°58.538'N 102°02.153'E, 19.vii.-26.vii.2006, Malaise traps, T. Jaruphan & O. Budsawong (T 225), 1 ♀; Chaiyaphum, Pa Hin Ngam NP, Dry evergreen forest at waterfall, 15°34.802'N 101°25.990'E, 430 m, 14.xi.-15.xi.2006, Pan traps, Katae Sa-nog & Buakaw Adnafai (T 1026), 2 ♀; Chaiyaphum, Pa Hin Ngam NP, Ecotone between mixed deciduous and dry dipterocarp, forest, 15°34.913'N 101°25.658'E, 444 m, 10.xi.-16.xi.2006, Malaise trap, Katae Sa-nog & Buakaw Adnafai (T 1031), 2 ♀.

Holotype and paratypes from Vietnam and two paratypes from Thailand are deposited in the Zoological Institute of Russian Academy of Sciences in St. Petersburg, Russia; other paratypes from Thailand in the Entomological Section of QSBG (Queen Sirikit Botanical garden; PO box 7, Mae Rim Chiang Mai 50180, Thailand).

Diagnosis. New species is similar to the Oriental species L. tenuicorne Malloch, Palaearctic

L. longicorne (Thomson) and Australian L. queenslandicum Spencer sharing a long postpedicel. It differs from L. tenuicorne by smooth not rugose ocellar triangle and yellow palpi, from L. queenslandicum by yellow palpi, brown ocellar triangle, more light colour of body and structure of male genitalia, and from L. longicorne by yellow palpi and legs, and brown ocellar triangle.

Description. Frons yellow, longer than wide. Ocellar triangle smooth, brown shining, its basal part extends to ½ length of frons and narrow part extends to anterior margin of frons. Ocellar tubercle dusted. Ocellar setae and setulae black. Ocellar, outer and inner vertical setae equal, postocellar very short.

Occiput yellow with black central part. Eyes bare. Face and gena yellow. Gena as wide as apex of postpedicel. Postpedicel 3 times longer than its width at base, tapering to apex, yellow with black apex. Arista white with yellow base. Palpi yellow.

Thorax yellow. Scutum mat with black fused stripes, leaving small yellow parts mesad of

postpronotum. Postpronotum yellow with black mark. Scutellum black with long apical and short lateral setae. Pleura yellow shining with black marks. Mark on katepistermum shining. Postnotum black dusted. Abdomen dark brown mat. Wing hyaline, veins brown. Second sector of costal vein 2.5 times longer than third. Veins R4+5 and M 1+2 weakly divergent. Transverse vein r-m beyond the middle of cell dm. Halteres brownish. Legs yellow.

Length of body 2–2.25 mm.

Distribution. Vietnam and Thailand.

Etymology. The species is named for the type locality: Tuly in Vietnam.

Remarks. L. longicorne Thomson has black palpi and infuscate femora, tibia and tarsi according Becker (1910), Sabrosky (1961) and Yang & Yang (1995). L. longicorne is up to now known only from China. Records from India ( Nartshuk, 1984; Yang & Yang, 1995) are mistaken, and based on misidentifications by Lamb (1917). Malloch (1927b) described the specimen from India, which Lamb (1917) called L. longicorne Thomson instead of L. tenuicorne Malloch. Sabrosky (1961) published the key for 3 Oriental species, and Yang & Yang (1995) the key for 5 Oriental and Palaearctic species of the genus. Three other species were later described, a species moved into the genus, and L. sequens Becker was recorded in the Arabian Peninsula. I propose a new key.

Figures

FIGURE 9 – 16. Structures of Lagaroceras spp. 9, 11 – 13, Lagaroceras tulense Nartshuk, sp. n. (orig.): 9, antenna. 11, epandrium, dorsal view; 12, epandrium, lateral view; 13, hypandrium and phallic organs, ventral view. 10, 14 – 16, L. nigrum Yang et Yang (after Yang et Yang, 1995): 10, antenna; 14, epandrium, dorsal view; 15, epandrium, lateral view; 16, hypandrium and phallic organs, ventral view.