Palpilongus, Couri, Marcia Souto & Carvalho, Claudio Jose Barros de, 2013

Couri, Marcia Souto & Carvalho, Claudio Jose Barros de, 2013, A new genus and species of Coenosiini from Costa Rica (Diptera, Muscidae, Coenosiinae), ZooKeys 321, pp. 25-34 : 26-28

Genus Palpilongus gen. n.

Type-species.

Palpilongus bifurcus sp. n., by present designation

Diagnosis.

(Fig. 1) Male dichoptic; eye bare, separated by about 1/3 of head width in both sexes; palpus flattened, very long with length equal to that of the prementum (Fig. 2); proepimeral seta oriented downwards; notum and pleurae with very few setu lae; presutural acrostichal setae developed; dorsocentral setae 1 + 3; katepisternals 1 + 1 + 1 forming an equilateral triangle; upper calypter truncate and very short; wing veins bare; male hind tibia with many rows of fine and long anterodorsal, dorsal and posterodorsal setae; sternite 1 bare; setae on sternite 5 bifurcated; hypandrium tubular in male; ovipositor long in female.

Etymology.

Derived from the Latin words palpus and longus, the genus name refers to the long palpus.

Discussion.

In the current classification of Muscidae , the new genus falls in the tribe Coenosiini of the Coenosiinae . In both keys to muscid genera identification of de Carvalho and Couri (2002) for the Neotropical region and Savage and Vockeroth (2010) for Central America, the new genus approaches Neodexiopsis and can be separated by the following couplet:

The new genus was added to the cladistic analysis of the world Coenosiini ( Couri and Pont 2000). The analysis positioned Palpilongus in the same clade of Cordiluroides + Neodexiopsis + Haroldopsis Albuquerque (synonymyzed with Neodexiopsis in the referred cladistic analysis), based on one synapomorphy - presence of three preapical setae on mid femur. The new genus was supported by the following synapomorphies: hairs on arista at most equal to basal width of arista; fronto-orbital plate with no setulae; colour of thorax and abdomen shinning undusted; notum almost bare, with very few ground setulae; lateral seta on scutellum present and hind tibia with a preapical posterodorsal seta at apical fourth.

Neodexiopsis and Cordiluroides are differently represented in the Neotropical region. Neodexiopsis is a speciose muscid genus, with about hundred described species found throughout the region, while Cordiluroides have a more restricted geographic distribution (Mexico, Costa Rica and Brazil) and is known by 6 species.

Most of the Neodexiopsis species have light brown to dark brown bodies, grey pollinose, and yellow to brown legs. Adults are small to medium sized predatory flies that inhabit forests or open habitats. Similarly to other genera of the Coenosiini tribe, the characteristic chaetotaxy of the hind tibia can distinguish one from each other. Neodexiopsis species can be recognized by the presence of one anterodorsal, one posterodorsal and one anteroventral setae in hind tibia, all near middle, the last one shorter and can be absent in some species. Besides this, the palpus is short and filiform, the upper calypter is glossiform and not reduced and the setae on sternite 5 are not bifurcated, as in Palpilongus gen. n.

Cordiluroides species can be recognized by the very high insertion of the antenna (very above the mid level of the eye), palpus short and slender, presence of only one pair of postsutural intra-alar seta, upper calypter transverse, hind tibia with one median anterodorsal, one posterior submedian and one posterodorsal supramedian setae and setae on sternite 5 not bifurcated. The genus was recently recorded from Costa Rica, on the base of three species ( Couri et al. 2006).