Silba tenuipennis, Introduction & Fallén & Morge, 2007

Introduction, Iain, Fallén, Lonchaea & Morge, Setisquamalonchaea, 2007, New pecies of Lonchaeidae (Diptera: Schizophora) from Asia, Zootaxa 1631, pp. 1-32 : 28-30

Silba tenuipennis sp. nov.

Description: Holotype male: Head: Eyes bare. Frons about one half eye width, parallel sided centrally, entirelly deep matt black, with short frontal and interfrontal setulae at most one fifth length of orbital setae, longer setulae present along anterior margin of frons. Orbital plate shining black and without setulae. Lunule with six setulae, ground colour brown but covered in silver dusting as are the parafacials and dorsal parts of the face. Anterior genal setulae in a single row of four to five anteriorly, none of these exceptionally strong. Antennal flagellomere entirelly black, two times as long as deep, not reaching mouth margin. Arista entirelly black, plumosity long, at its greatest extent just longer than depth of antennal flagellomere.

Thorax: Disc shining black, with some prescutellar dusting, bearing setulae one third length of orbital setae. Anepisternum with two strong anterior setae and three posterior. Katepisternum with only one setae, with anterior to it, a few long thin setulae. One propleural and one stigmatical setae. Prothorax bearing setulae. Scutellum with disc shining grey metallic, on margin two short setulae between lateral and apical setae and two between apical setae. Squamae pale with pale margins and fringes. Wings lightly fumose. Wing length 3.7 mm. Legs, entirelly black.

Male terminalia; Figs. 63–65. In lateral view epandrium two times as high as wide, rounded posteriorly with a rather square, short process apically, a row of short setulae present along most of ventral margin. Surstyli only extending beyond the shell of epandrium posteriorly as a small, rounded process. Cerci small, only extending slightly past the posterior margin of the epandrium, sclerotised on apical part which bear a row of moderately long setulae along the ventral and dorsal margins. In ventral view surstyli on inner margin with a row of seven small, blunt, black teeth, one spine-like setulae present on each side at the base of the cerci. Aedeagus a relatively simple J-shape, with a small process on inner margin basally, apical half very thin and straight.

Female: unknown

Differential diagnosis: this appears to be quite a unique Silba species having only one strong setae on the katepisternum, a characteristic which is present on all the specimens examined. It also possesses a very characteristic aedeagus with a long, thin apical portion. With a relatively simple J-shaped aedeagus this species shows some affinities with the common S. perplexa but it is easily separated by the features outlined above.

TYPE MATERIAL: Holotype male. THAILAND: Nan Prov. Mae Charim waterfall, No.25, over and along rivulet, 7–8.xi.2004, leg. Papp & Földvári.

Paratypes: Trang Prov., Khao Chong Botanic Garden , along forest path, 20.xi.2004, No. 41, leg M. Földvári, 1 male . Nan Prov. Mae Charim waterfall, No. 25, over and along rivulet, 7–8.xi.2004, leg. Papp & Földvári, 2 males Nan Prov. Ban Na Lae nr. Pua , 05.xi.2004, over a rocky forest brook, No. 19, leg. Papp & Földvári, 1 male Fang, Mae Fang N. P. Headquarters, No. 7, 19.xi.2003, leg Peregovtis et. Al., 1 male .

Holotype and paratypes listed above in the HNHM .

Chiang Rai Prov., Mae sai Distr., nr. Phayanak cave , 460m, 20°22’N / 99° 52’E, 16–18.xii.2003, P. Schwendinger leg., secondary forest, 1 male .

Phuket Prov., Siray isl. , E . Phuket city, 22–26.vii.2002, 7°53’N / 98°26’E, P. Schwendinger leg., secondary forest, 1 male .

Trat prov., Ko Chang , 12°03’N / 102°18’E, (no further data on pin), 1 male .

Paratypes listed above in the MHNG .

Etymology. The specific epithet refers to the attenuated apex to the male aedeagus.