Description of Dichelacera ( Dichelacera ) matogrossensis sp . nov . ( Diptera , Tabanidae ) of Brazilian Midwestern

Dichelacera matogrossensis sp. nov. is described based on females from the Chapada dos Guimarães, state of Mato Grosso, Brazil. Diagnosis, discussion and illustrations are provided.

This material examined here was obtained by recent systematic sampling conducted as part of a large project that aims is improvement the knowledge of Diptera in the Brazilian states of Mato Grosso, Mato Grosso do Sul and Rondônia.A new species of Tabanidae is described here.
All specimens were fixed in alcohol first, the thorax and abdomen are somewhat crumpled and the pilosity are partly missing.

Dichelacera matogrossensis sp. nov.
(Figs 1-9) Diagnosis.Frons with parallel sides.Face including frontoclypeal pits pruinose.Wing apex at most fumose contrasting with fascia brown, step-like.Posterior half of basal posterior and extreme base of discal cell brown infuscated.Interalar dark band of thorax wider than pale prescutellar band.Antennal spine not reaching second flagellomere.Flagellum subequal than distal segment of palpus.
Scutum pale brown with yellowish gray pruinosity and yellow pilosity, a large dark brown interalar band and narrow yellowish pale prescutellar band.Scutellum brown with short brown hairs.Notopleural lobe yellowish gray with predominant yellowish hairs; pleura and sternum yellowish gray with yellowish hairs.Wing as figured (Fig. 5), inferior calyptra brown, halter pale yellow.All coxae pale yellow.Femora dark yellow.Fore tibiae bicolored, white with white hairs on proximal 2/3 and brown with black hairs on apical 1/3.Mid tibiae white with pale hairs except for apical 1/4 pale brown with dark hairs.Hind tibiae and all tarsi brown with black hairs.Tergites 1-5 brownish yellow with posterior whitish margins.Tergites 6-7 brown.Sternites pale brownish yellow with yellow hairs.9).Tergites IX and X, cercus and hypoproct as in Fig. 6.Tergite IX divided (not fused), partially destroyed but apparently subequal to tergite X. Tergite X divided into two pieces, subrectangular.Cercus longer than large, with apex slightly acuminated.Hypoproct with apex acuminated, exceeding the half of the cercus length.Hypogynium + hypogynial valve (Fig. 7).Hypogynium with lateral margins slightly rounded, anterior and posterior margins little narrowed.Genital fork (Fig. 8) with reduced arms without distal expansions; tuft of setae on distal extremities of arms; anterior margin slightly excavated; sperm pump sclerotized with circular ridge expansions, shorter than genital fork.Spermathecal capsule slender, apex slightly acuminate and esclerotized, brown pigmented (Fig. 9).
Variations.Length: 9.9 -10.Etymology.The specific name refers to the state of Brazil where the specimens was recorded, Mato Grosso.

DISCUSSION
Dichelacera matogrossensis sp.nov. is easily differentiated from other species of the Dichelacera (Dichelacera) by the darkening of the posterior half of the posterior basal cell and the base of the discal cell; this character is exclusive for this species in the subgenus.Fairchild & Philip (1960:7) at characterization of the genus commented: "The second basal cell and base of the discal cell are almost always hyaline, even those cases where the wing is extensively infuscated".