Corethrella (Corethrella) aurita Borkent, 2008

Amaral, André P., Mariano, Rodolfo & Pinho, Luiz Carlos, 2023, Description of five new species of frog-biting midges (Diptera, Corethrellidae) from Brazil and examination of new morphological characters with utility for taxonomic and phylogenetic studies, European Journal of Taxonomy 874 (1), pp. 1-120 : 59-61

Corethrella (Corethrella) aurita Borkent, 2008

Fig. 28 ; Appendix 1

Material examined

BRAZIL – Bahia State • 2 ♀♀, adults; Rio de Contas, RPPN Volta do Rio , stream; 13°32ʹ07ʺ S, 41°54ʹ44ʺ W; 1318 m a.s.l.; 1 Dec. 2019; A.P. Amaral leg.; frog-call trap ( Boana faber ); CE-MHS • 2 ♀♀, adults; Rio de Contas, Parque Natural Serra das Almas , “ brejo do junco ” [reed marsh]; 13°32ʹ19ʺ S, 41°52ʹ36ʺ W; 1202 m a.s.l.; 2 Dec. 2019; A.P. Amaral leg.; frog-call trap (chorus); CE-MHS • 1 ♀, adult; same collection data as for preceding, except 3 Dec. 2019; CE-MHS .

Description

Female adult (n = 5)

HEAD. Sensilla ( Fig. 28A ): Ocular row with 2 thick offset setae at ventral part, 1 more dorsal, and 16–18 setae extending to mid-posterior portion of head. Subocular row not well-defined anteriorly, with 3 setae shortly extending posteriorly; interocular space and vertex with multiple slender setae. Postgenal row with 9 intermediate and 7 slender setae, located at mid-posterior portion. With 2 thick ventromedial setae.

THORAX. Sensilla ( Fig. 28B ): Antepronotum with 3–6 slender anterodorsal setae; 3–4 thick and 4–9 slender setae along ventrolateral margin. Postpronotum with 2 thick dorsal setae and 3–5 slender posterior ones. Scutum, prescutal area with 3 thick setae near prescutal suture, 5–9 dorsal slender setae, reaching dorsocentral row; group of 8–12 intermediate and 6–15 slender setae more anteriorly, merging with anterior portion of dorsocentral row. Antealar area with 4–6 thick/intermediate setae vertically aligned on anterior portion; 6–9 thick and 12–15 slender setae ventrally located; 16–30 slender setae more dorsally, reaching dorsocentral row. Supraalar area with 4–5 thick setae surrounded by 12–20 slender setae. Dorsocentral row, posterior part with cluster of 4–5 thick setae; 19–24 thick/intermediate and 41–55 slender setae filling row. Scutellum with 11–12 thick setae. Posterior anepisternum bare. Anepimeron with 15–20 slender setae.

WING. R 3 /R 1: 0.49 (0.47–0.53); R 2+3 /R 2: 0.71 (0.62–0.76).

LEGS. Empodium ( Fig. 28C ) of intermediate length and thickness, with 6 branches. Ta1/Ta2: 2.63 (2.59– 2.72); Ta3/Ta4: 1.05 (1.00–1.09).

Distribution and biology

This is the first record of Corethrella aurita in Brazil. Specimens were collected with frog-call pan traps in Rio de Contas, Bahia, playing the calls of Boana faber , Physalaemus cuvieri and P. nanus near a large marsh area and a small stream. The sampled areas are part of the Espinhaço mountain range, in xeric shrubland (caatinga biome). Altitudes range from 1202 to 1318 m a.s.l.

This species was previously known only from the type locality in Panama, at an altitude of 27 m a.s.l. ( Borkent 2008).

Remarks

Even though the specimens closely match the species description ( Borkent 2008: 122), the extension of its distribution and altitudinal range is remarkable, as Corethrella aurita was previously known only from Panama at an altitude of 27 m a.s.l.

In fresh specimens a darkly pigmented heart-shaped spot on the posterior portion of the scutum was observed, and it is not known whether that pattern is present on the type specimens. The description mentions a patterned scutum, which might be the case.

Figures

Fig. 28. Corethrella aurita Borkent, 2008, female adult. A. Cranial setae, anterior and posterior views, and clypeus in anterior view. B. Thoracic setae, lateral view. C. Hind leg claw and empodium, lateral view.