Trichocera (Saltrichocera) sardiniensis, Petrašiūnas, Andrius, 2009

Petrašiūnas, Andrius, 2009, A new species of Trichocera Meigen (Diptera: Trichoceridae) from Sardinia, Zootaxa 2108, pp. 62-64 : 62-64

Trichocera (Saltrichocera) sardiniensis sp. nov.

( Figs. 1–9 )

Etymology. The species is named after the type locality – Sardinia Island, Italy.

Material examined. Holotype male, labeled „I – Sardegna (Cagliari)/ Iglesias Marganai, 700m / Plot Conecofor SAR1/ UTM 32S 462853 4355582/ 12.XII.2003 – 8.I.2004, Malaise trap/ G.Chessa legit./ Conecofor programme - CNBF “, in alcohol ( MZVU). Paratypes (5 males, 11 females): 1 male, 2 females with same data (British Museum (Natural History), London - BMNH); 1 male, 2 females with same data except „ 8–21.I.2004 “( ISEZ); 1 male, 1 female with same data except „ 21.I–16.II.2004 “; 1 female with same data except „ 15–30.VI.2004 “; 1 female with same data except „ 22.XI–17.XII.2004 “; 3 females with the same data except „ 1.III–29.IV.2005 “ (all in alcohol); 1 female in glycerol, with same data except „ 17.XII.2004 – 04.I.2005 “; 1 male in glycerol, with same data except „ 18.I–01.III.2005 “; 1 male, in glycerol, labeled „I - Sardegna (Carbonia-Iglesias)/ Iglesias, Conca Margiani, radura 725m / UTM-WGS 84 32S 0 464970 4357011/ 15.XI.2006, retino da sfalcio/ G. Nardi leg./ Progetto Sardegna - CNBF “ (all in Museum of Zoology of Vilnius university, Vilnius, Lithuania – MZVU, if not noted otherwise).

The drawings were made by tracing the photographs.

Diagnosis. A comparatively small species. Body color brown to dark brown. Plaurae bare. First flagellomere of male antenna long-oval, slightly broader than the following ones, that of female antenna fused with the second one, producing large compound formation. R2+3+4 shorter or sub-equal to R2+3. Male IX sternite not incised medially, set with bristles all along distal margin. Male terminalia with bridge very low and broad, gonostylus parallel-sided, with very distinct tubercle at inner base. Female with slender, weakly bent ovipositor, sub-equal to 1.1 times longer than the genital segment; setulose area narrow, clearly delimited. Body length 5–6 mm, wing length 5–7 mm.

Description. Relatively small species, male body and wing size around 5 mm, female body size around 6 mm, wing size 6–7 mm. Body color brown to dark brown. Pleurae bare.

Male antenna ( Fig. 1 ) short, nearly reaching the abdomen. First flagellomere slightly broader than following ones; f1 1.5–1.8 times longer than f2 and 2.1–2.7 times longer than pedicel. Flagellomeres decrease in length from the 1st to the 4th one and increase in length distally starting from the 5th one. Verticils three to four times as long as pubescence. First flagellomere has some flattened setulae (better expressed in females) near the base, visible only under high magnifications (e.g. x40).

Female antenna ( Fig. 2 ) rather distinct, with f1 and f2 fused. The compound formation about 2.4 times as long and 2 times as broad as the third flagellomere. The latter and following segments cylindrical, increasing in length distally, with verticils two to three times as long as pubescence. Female fused element is covered with peg-like and flattened setulae ( Fig. 2 ), this feature being similar to that reported in T.(S.) antennata Starý and several other species ( Starý, 1999).

Wing tinged with brownish, veins brown. Sc covered with setae all along its length both dorsally and ventrally. R2+3+4 shorter or sub equal to R2+3. Rs with numerous setae both dorsally and ventrally. Discal cell narrow, triangular in shape ( Fig. 3 ), 2.4–2.6 times as long as wide. Vein bM1+2 almost half of mM1+2. A2 dorsally covered with macrotrichia up to the bend, and is situated close and parallel to the wing margin.

Legs. Tarsal claws ( Fig. 4 ) in male short and weakly curved, less than 1/3 of t5. Bases of trochanters light brown, gradually darkening distally. Further parts of legs uniformly dark brown.

Hypopygium ( Fig. 5 ) with sternite IX with slight medial incurvation and about 8 setae along posterior margin. Gonocoxal bridge very low, broad, wide in ventral view. Gonostylus slightly longer (~ 1.3 times) than gonocoxite, parallel-sided, tip rounded, with very distinct basal tubercle. Complex of aedeagus ( Fig. 6 ) with parameres of moderate length, parallel in ventral view, narrow in basal part. Lateral apodemes rounded. Basal apodemes broad, parallel in ventral view. Aedeagal apodeme finger-like, rather long, ~1/4 of aedeagus.

Female ovipositor ( Fig. 7 ) sub-equal to slightly (~ 1.1 times) longer than genital segment, slender, almost straight. Setulose area narrow, clearly delimited, covering more than 1/3 the length of ovipositor. Genital plate quadrangular, with conspicuous medial incision, fork of the genital plate semicircular ( Fig. 8 ). Supragenital plate with acute tip and two (sometimes three) bristles. Sclerotized parts of the spermathecal ducts slightly shorter than spermathecal diameter ( Fig. 9 ).

Remarks. The correspondence of males to females was established by general body coloration, triangular d-cell and similar shape of tarsal claws. Moreover, only specimens of T. (S.) annulata Meigen , T. (S.) rufescens Edwards and T. (S.) saltator (Harris) were present in the studied material from Sardinia and all of these species are clearly distinct from T.(S.) sardiniensis sp. nov.

The new species resembles T. (S.) antennata most of all by short peg-like setulae on fused and enlarged female flagellomeres and general shape of the ovipositor. First flagellomere is also quite similar in males of both species by the form and peg-like setulae. On the other hand, T.(S.) sardiniensis sp. nov. differs from T. (S.) antennata by the form of female genital fork and by having only two bristles on supragenital plate. It also differs by males having distinct projection at inner base of gonostyles, almost straight IX sternite, different aedeagal complex and comparatively short, less curved tarsal claws. Finally, both males and females of T. (S.) sardiniensis sp. nov. have no setae on pleurons contrary to the state in T. (S.) antennata .

The newly described species is also very similar to recently redescribed ( Dahl & Krzeminska, 2008) T. (S.) borealis Lackschewitz by the general view of male and female terminalia. Males of both species have distinct basal tubercle at inner base of gonostylus, straight margin of IX sternite with setae all along it, but the gonocoxal bridge in T.(S.) sardiniensis sp. nov. is low and broad compared to the high and narrow bridge in T. (S.) borealis . The base of parameres in T. (S.) borealis is wider, while basal apodemes narrower than those in T. (S.) sardiniensis sp. nov. Male tarsal claws exceed half of fifth tarsomere in T. (S.) borealis whilst they reach only 1/3 of the tarsomere in T. (S.) sardiniensis sp. nov. The shape of the ovipositor is rather similar in females of both species. Females of T. (S.) borealis and T. (S.) sardiniensis sp. nov. are also similar by having two setae on supravaginal plate, but vaginal apodeme in T. (S.) borealis has very short lateral portions compared to longer and parallel lateral portions in T. (S.) sardiniensis sp. nov.

Figures

FIGURES 1 – 9. Trichocera (Saltrichocera) sardiniensis sp. nov.: 1) male antenna, proximal segments (paratype, Iglesias Marganai, 18. I- 01. III. 2005); 2) female antenna, proximal segments (paratype, Iglesias Marganai, 17. XII. 2004 - 04. I. 2005); 3) discall cell; 4) male tarsal claw (both paratype, Iglesias Marganai, 18. I- 01. III. 2005); 5) general view of male terminalia, latero-ventrally; 6) male terminalia, aedeagal complex, lateral (both paratype, Iglesias Marganai, 18. I- 01. III. 2005); 7) shape of ovipositor, lateral view; 8) genital plate; 9) spermathecae (all three paratype, Iglesias Marganai, 17. XII. 2004 - 04. I. 2005). Scales = 0.25 mm.