Notiocoenia Mathis

Mathis, Wayne N. & Marinoni, Luciane, 2016, Revision of Ephydrini Zetterstedt (Diptera: Ephydridae) from the Americas south of the United States, Zootaxa 4116 (1), pp. 1-110 : 14-15

Genus Notiocoenia Mathis

Notiocoenia Mathis 1980: 12 [type species: Notiocoenia paniculata Mathis 1980 , original designation].—Lizarralde de Grosso 1989: 59 [fauna of Argentina].— Mathis and Zatwarnicki 1995: 249 –250 [world catalog].

Diagnosis. Specimens of Notiocoenia are similar to those of Coenia Robineau-Desvoidy but are distinguished from the latter and other genera of Ephydrini by the following combination of characters: Small to moderately large shore flies, body length 1.90–4.20 mm; mostly grayish brown to brown, generally appearing dull but subshiny to shiny over much of dorsum.

Head: Wider than high from anterior view; frons mostly flat, wider than long, vestiture more or less uniform, dull, microtomentose, mostly unicolorous brown, margins of mesofrons indicated by shallowly impressed furrow, otherwise undifferentiated from parafrons, lacking large setae, cruciate or otherwise; well-developed, lateroclinate, fronto-orbital setae 2, plus 1 much smaller proclinate seta anterior of larger setae; paravertical seta small, inconspicuous, none 1/2 length of vertical seta; well-developed, ocellar setae 1, slightly divergent; small postocellar setae 2–3 setulae; medial vertical setae well developed, lateral vertical seta either well developed or lacking. Antenna normally developed, dark colored, basal flagellomere considerably longer than high, rounded apically; pedicel bearing several setae, especially on medial and ventral surfaces, bearing 1 large, dorsally erect seta on dorsum; arista longer than combined length of other antennal segments, macropubescent or bearing short hairs dorsally. Face protuberant, broadly transversely arched, setulose to setose; interfoveal hump evident but variously developed; vestiture densely microtomentose. Eye subspherical, slightly higher than wide. Gena short, gena-to-eye ratio 0.20 or less; well-developed, genal seta 1. Mouthparts generally retracted into oral opening, clypeus not exposed; maxillary palpus dark; prementum longer than wide; microtomentose to microtomentose, setose.

Thorax: Vestiture variable, dull to shiny, generally becoming shinier posteriorly; coloration grayish brown to blackish brown. Pleural areas generally becoming paler colored ventrally; humeral callus, part of anepisternum, and katepisternum grayish tan to whitish tan, otherwise pleural areas darker brown; forecoxa gray to silvery gray, contrasting with remainder of pleural areas. Chaetotaxy as follows: Acrostichal setae when present arranged in 2 rows, larger setae mostly anterior of transverse suture; lacking well-developed, prescutellar seta; well-developed, dorsocentral setae 4 (1+3), rarely 5 (2+3), anterior 1–2 setae smaller, several smaller setae anterior of larger setae; interalar setae 2, anterior seta inserted just posterior of transverse suture, posterior seta posterior of level of posteriormost dorsocentral seta; postpronotum either bare or bearing 2–3 setulae, none more than 1/4 length of posterior, notopleural seta; presutural interalar seta 1; interalar setae 2, rarely 3, anterior seta inserted just posterior of transverse suture, posterior seta smaller, inserted just posterior of posteriormost dorsocentral seta; postsutural, supra-alar seta variable; postalar seta well developed; disc of scutellum mostly bare, bearing 2–3 setulae, or bare; lateral scutellar setae 2; notopleural setae 2, inserted near each ventral angle; anepisternal seta 1, inserted near middle of posterior edge, numerous smaller setae, particularly toward dorsal and posterior margins; prosternum bare; katepisternal seta 1, with 1–2 smaller setae around larger seta; midcoxa with 1 larger seta. Wing hyaline to palely infuscate; R stem vein bare dorsally. Halter yellowish to pale brown. Legs variable, femora swollen to slender; coloration rufous to black; pulvilli well developed; tarsal claws short and distinctly curved; pulvilli well developed; tarsal claws short and distinctly curved; hindfemur of male not differing markedly from fore- or midfemur, lacking stout setae as above; hindtibia of male lacking tuft of setulae; hindtarsi of male cylindrical, normal.

Abdomen: Male terminalia as in species-group diagnoses.

Distribution. The composite distribution of this genus extends from 24°–53°S along the east and west slopes of the Andes Mountains.

Discussion. Although the monophyly of Notiocoenia appears to be well established, its relationship within Ephydrini is not as evident. Although we suggest a sister group relationship with Coenia , which we think is correct, the evidence to support this alliance is not altogether convincing.