Thitena, Munari, 2004

Munari, L., 2004, Beach Flies (Diptera: Tethinidae: Tethininae) From Australia and Papua New Guinea, with Descriptions of Two New Genera and Ten New Species, Records of the Australian Museum 56 (1), pp. 29-56 : 50-51

Thitena n.gen.

Type species. Thitena cadaverina n.sp. ( Fig. 29).

Diagnosis. Robust, yellowish brown flies with legs bearing strong setae and long and thick villosity which is particularly developed in male; head roundish; face depressed, bearing shining, foldlike tubercle above vibrissal angle; cephalic chaetotaxy typical of subfamily; frons without discernible golden patch on both sides of ocellar triangle, only with slight infuscation; arista microscopically pubescent; eye roundish, with few, sparse interfacetal setulae; longest diameter of eye over 3.5× as long as genal height. Thorax very slightly flattened dorsally, with chaetotaxy typical of subfamily; disc of scutellum pubescent ( Fig. 30); all thoracic setae distinctly thinner than those in all other Tethininae . Legs very robust, strongly villose, particularly forelegs in male (an apomorphic character state with respect to the ground plan of the Tethinidae ); tarsi of male stumpy, with tarsomeres noticeably short (in particular basitarsomeres), setulose, and flattened; true ctenidium absent; tibiae with rows of strong setae. Wing typical of subfamily; halter pale yellow. Abdomen rather robust, with tergites and sternites well sclerotized; male terminalia ( Figs. 31–32) with very long and slender anterior surstylus, and large posterior surstylus externally covered with dense microtrichia; both surstyli subequal in length and reciprocally parallel. Spermathecae of female spherical, smooth.

Remarks. For some morphological and chaetotactic traits as well as for the general habitus, the new genus would seem to be related to Pseudorhicnoessa , differing from it particularly for the following characters besides those given in the key: larger size; body and legs distinctly more robust and setulose; frons with numerous additional setulae; thoracic setae distinctly thinner; true ctenidium of fore femur absent; fore tibia with row of strong setae; mid and hind tibiae with different chaetotactic pattern; tarsi of male stumpy, with tarsomeres noticeably short (in particular basitarsomeres), setulose, and flattened; crossvein dm-cu longer, about as long as half of last section of CuA 1; abdomen with sternites well sclerotized; male terminalia with anterior and posterior surstyli subequal in length and reciprocally parallel.

Etymology. The generic epithet derives from an anagram of the generic name Tethina . Gender feminine.