Limnellia Malloch

Costa, Daniel N. R., Savaris, Marcoandre, Marinoni, Luciane & Mathis, Wayne N., 2016, Two new, brachypterous Limnellia species from the Venezuelan Andes (Diptera: Ephydridae), Zootaxa 4144 (3), pp. 301-315 : 304

Genus Limnellia Malloch

Limnellia Malloch 1925: 331 (feminine). Type species: Limnellia maculipennis Malloch 1925 , original designation.─ Andersson 1971: 53 –59 [review, European species].─ Mathis 1978: 250 –293 [revision of Nearctic species].─ Mathis 1980 [review, Neotropical fauna].─ Zhang and Yang 2009: 558 –64 [review, Chinese fauna].─ Krivosheina 2012: 1 –7 [review, Russian species].─ Mathis et al. 2014: 563 –564 [review, Brazilian species].

Eustigoptera Cresson 1930: 126 (feminine). Type species: Notiphila quadrata Fallén 1813 , original designation.─ Cresson 1935: 362 [synonymy].

Stictoscatella Collin 1930: 133 (feminine). Type species: Notiphila quadrata Fallén 1813 , original designation.─ Cresson 1935: 362 [synonymy].

Stranditella Duda 1942: 30 (as a subgenus of Lamproscatella ; feminine). Type species: Notiphila quadrata Fallén 1813 , original designation.─ Dahl 1959: 126 [synonymy].

Diagnosis. Limnellia is distinguished from other genera of the tribe Scatellini by the following characters: Small to moderately small shore flies, body length 1.00– 2.50 mm; mostly dark brown to black, microtomentose to bare, shiny, frequently with cinereous guttate and vittate maculae; wing maculate, generally dark with white spots. Head: Mesofrons distinct from duller parafrons, sometimes subshiny; lateroclinate fronto-orbital seta 1 (rarely 2); inner and outer vertical setae both well developed; paravertical setae either reduced or absent; ocelli arranged in isosceles or equilateral triangle or absent. Arista at most macropubescent. Face with shallow antennal grooves; interfoveal carina not projected or creased dorsally; facial setae mostly small, hair-like. Eye nearly round. Gena relatively short, bearing 1 well-developed seta. Thorax: Acrostichal setae uniform in size, small, arranged in 2 rows that extend to base of scutellum; dorsocentral setae 2 (0+2); supra-alar seta either reduced or lacking; disc of scutellum bare; lateral scutellar setae usually 2, sometimes 1 or lacking. Wing maculate, mostly dark brown with white, generally guttate markings. Abdomen: Tergites black, becoming shiny and polished posteriorly. Male terminalia: Epandrium a closed plate around cercal cavity, bearing articulated surstyli on anterior margin; gonites elongate with broad base, bearing setae on ventral portion; phallapodeme in lateral view nearly straight or deflected medially; dorsal aedeagal opening with a fold along ventral margin; aedeagus without distiphallus; ejaculatory apodeme usually present, small.

Discussion. With description of the two new species below, Limnellia now includes 24 species worldwide ( Mathis and Zatwarnicki 1995 and electronic updates) that occur in most temperate regions or at higher elevations in subtropical and tropical zones. Only two species were known previously from Neotropical Region , L. huachuca Mathis ( Colombia, Jamaica, Mexico, and Porto Rico ) and L. itatiaia Mathis ( Brazil) ( Mathis 1980, Mathis et al. 2014). Two species in the genus exhibit brachyptery of two different types: L. helmuti Hollmann-Schirrmacher and Zatwarnicki has a short and broad wing, and L. abbreviata , has a narrow wing. Both species are incapable of flight.

The two new species described herein are closely related (see “Remarks” sections below) and form a lineage within Limnellia that seems to have arisen and diversified due to evolutionary pressures within the Paramo or during the development of this ecosystem.