Aphaniosoma soror, Ebejer, Martin J., 2016

Ebejer, Martin J., 2016, The Moroccan species of Chyromyidae (Diptera) with descriptions of five new species of Aphaniosoma Becker, Zootaxa 4208 (3), pp. 221-236 : 229-230

Aphaniosoma soror sp. n.

Figs 9–10

Diagnosis. A grey species with greyish yellow pollinosity and completely yellow legs; head rather flattened; frons with an exceptionally long a pair of setae in front of ocellar triangle; pleural sclerites and abdominal tergites narrowly bordered in yellow.

Description. Male: Head: rather flat and all yellow except for black ocellar triangle; frons distinctly longer than broad, ratio approximately 10:8, markedly narrowed anteriorly, at level of antennae 0.5 width that at level of anterior ocellus; eye quite elliptical lying obliquely; gena narrow in front, deeper behind, in profile, below middle of eye, about 1/3 height of eye, with numerous glistening pale golden yellow setulae; occiput in profile barely visible behind eye, black except for narrow yellow postocular border; postocular setulae irregularly in one row; mouth parts all yellow; 2 vibrissal setulae moderately developed: longest about equal to anterior orbital seta; face short, poorly sclerotized and depressed; median carina short and narrow, only visible just below lunule; antenna yellow, pedicel paler than postpedicel with distinct short seta dorsally; postpedicel with fine but distinct pubescence along anterior margin longer than diameter of basal segment of arista; 1st segment of arista yellow in basal half, distal half and second segment brown, with fine pubescence; chaetotaxy: 2 strong orbitals, with 2 short setulae in front, postverticals short and convergent; 1 medial vertical and 1 lateral vertical, both strong; ocellars long, proclinate and diverging; about 8 short setulae across middle of frons with another pair much longer than these situated in front of ocellar triangle and reaching very close to anterior margin of frons.

Thorax: scutum, scutellum and pleura dark grey and greyish yellow pollinose; metanotum black; pleural sclerites bordered yellow; chaetotaxy: 1 postpronotal, 1 incurved internal post-postpronotal, 1 presutural, 2 notopleural, 0+3 intra-alar, 1 postalar, 3+4 dorsocentral, only one prescutellar seta, strong, 6 acrostichals, distance between their rows about equal to that separating them from dorsocentral rows, with prescutellars not developed, 4 scutellars, 1 anepisternal with 2 setulae below it, 1 katepisternal at upper posterior corner with 4 setulae vertically down middle of sclerite.

Wing: veins all pale brown; distance on costa between R2+3 and R4+5 about 0.4 that between R4+5 and M; distance between cross veins about 1.4 length of posterior cross vein, which sits at right angles to M vein and is about 0.3 length of apical section of vein Cu. Haltere pale yellow.

Legs: yellow, not modified except for slightly thicker femora; numerous pale setulae scattered on all pairs of legs, in addition longer setulae present on fore femur; apico-ventral seta on mid tibia present dark and long; claws black and pulvilli normal; 5th tarsomere of all legs brown; hind trochanter not modified.

Postabdomen Figs 9–10 : epandrium small and subshining dark brown in contrast to pale creamy yellow posterior part of hypandrium and pregonite; surstylus dark, distinct and curved; cerci small and pale; postgonites almost translucent yellow; distiphallus short, more or less simple tubular, mostly membranous.

Female: identical to male except for secondary sexual characters and brown postpedicel.

Body length: male 1 mm, female 1.1 mm, Wing length: male 1.3 mm, female 1.4 mm.

Variation. Unable to comment because of few specimens.

Etymology. The species epithet taken from the Latin soror , meaning sister, refers to the marked similarity of this species to A. subtilis Ebejer, 2006 described from Kyrgizstan.

Material. Holotype: male, eastern High Atlas , Errachidia, 14 km E of Rich, 32°15.242ʹN 04°23.211ʹW, 1278 m, 4.v.2012, MJE (registration number: NHMUK 010579840 ) . Paratypes: 1♂ 1♀, same data and depository.

Similar species. The new species is very similar to A. subtilis from which it differs in the much smaller distiphallus, the shape of sternite 6, and the more acute tip of the posteroventral process of tergite 6. Another similar species is A. serpens Carles-Tolrá , described from Spain. In this species, the frons is broader than long, the scutum is vittate, the acute process of tergite 6 is directed anteriorly and sternite 6 is quite differently shaped.

Figures

FIGURES 9 – 10. Aphaniosoma soror sp. n. 9) postabdomen lateral, 10) sternite 5 ventral. Abbreviations: ph apd = phallapodeme, prg = pregonite, psg = postgonite, tg 6 = tergite 6, ep = epandrium, cerc = cercus, st 6 = sternite 6, hyp = hypandrium, surs = surstylus. Scale bar = 0.15 mm.