Corethrella (Corethrella) pindorama Amaral & Pinho, 2023

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 : 11-12

Corethrella (Corethrella) pindorama Amaral & Pinho sp. nov.

urn:lsid:zoobank.org:act:588B1BA0-A51D-4889-B3C4-76DE9118C8DE

Fig. 4

Diagnosis

Female adult

Only extant species with the following combination of characters: coronal suture elongate, reaching ventral margin of interocular space ( Fig. 4B ); posterior anepisternum undivided, dorsoventrally elongate; mediotergite pale with a dorsal dark spot; plain wings with narrow scales on non-marginal veins ( Fig. 4J ); halter distinctly lighter than scutellum ( Fig. 4G ). Male unknown.

Etymology

The specific epithet – pindorama – is a Tupi-Guarani word regarded as the original name of the Brazilian region.

Material examined

Holotype

BRAZIL – Bahia State • ♀, adult; Lençóis, Trilha Ribeirão do meio ; 12°34ʹ26ʺ S, 41°23ʹ28ʺ W; 395 m a.s.l.; 19 Aug. 2019; A.P. Amaral leg.; frog-call trap ( Bokermannohyla oxente ); MZUSP.

Paratypes

BRAZIL – Santa Catarina State • 2 ♀♀, adults; Santo Amaro da Imperatriz, Plaza Caldas ; 27°44ʹ30ʺ S, 48°48ʹ07ʺ W; 460 m a.s.l.; 31 Jan. 2013; A. Ambrozio-Assis leg.; frog-call trap ( Boana bischoffi ); CE-MHS.

Description

Female adult (n = 3)

HEAD ( Fig. 4A ). Medium brown. Outline nearly circular in anterior view, about 1.3 times as wide as long. Coronal suture complete, reaching ventral margin of interocular space. Clypeus ( Fig. 4B ) wide, 1.27 times as wide as long, 3–6 dorsal setae of equal thickness. Mandibles serrate. Palpus ( Fig. 4C ) of same color as head, third segment clavate, about 1.2 times length of fifth.Antenna uniformly dark brown ( Fig. 4D ), with flagellomeres ( Fig. 4E ) I–III elongate. Flagellomere XIII apically bifurcated. Sensilla coeloconica distribution: 1(X–XIII), 3(I). Sensilla: Ocular row with 1 thick offset seta at ventral part, 11–12 more dorsally, extending posteriorly just beyond vertex. Subocular row with about 14 setae, posteriorly past ocular row. Postgenal row with about 7 slender setae, from posterior end of ocular row to ventromedial portion. With 1 thick ventromedial seta.

THORAX ( Fig. 4F–G ). Medium brown, with following sclerites pale: anterior and posterior anepisterna, dorsal and ventral portions of anepimeron, ventral mediotergite, dorsal portion of metepisternum. Dorsal portions of anterior anepisternum and of mediotergite with dark spots. Prescutal suture elongate, almost reaching dorsocentral row of setae. Anterior anepisternum divided longitudinally by sinuous suture. Posterior anepisternum undivided, dorsoventrally elongate. Sensilla ( Fig. 4H ): Antepronotum with 0–1 intermediate anterolateral seta and 4–5 slender ones along ventrolateral margin. Postpronotum with 1 thick and 3–5 slender dorsal setae. Scutum, prescutal area with 2 thick setae dorsoventrally aligned on posterior portion, 2–3 thick anteroventral setae, and 4–6 intermediate/slender setae scattered between them. Antealar area, anterior portion with 4–6 thick/intermediate setae loosely aligned dorsoventrally; 3–4 thick posterior setae, 20–24 slender setae spread from ventral to dorsal portions. Supraalar area with 3 thick anteroposteriorly aligned setae, 4–5 slender setae surrounding. Dorsocentral row, posterior portion with 2 thick and 1 slender offset setae; 19–27 thick/intermediate and 17–27 slender setae filling row. Scutellum with 8 thick setae. Posterior anepisternum with 3–4 slender setae at dorsal portion. Anepimeron with 1 intermediate and 0–1 slender seta centrally located.

WING ( Fig. 4I–J ). Greyish-brown, without pattern of pigmentation. Non-marginal veins with very narrow scales, resembling thick setae. Apex of R 2 basal to apex of M 1. Halter lightly pigmented, distinctly lighter than scutellum. R 3 /R 1: 0.64 (0.60–0.69); R 2+3 /R 2: 0.43 (0.29–0.56).

LEGS ( Fig. 4F ). Medium brown. Mid-, hind trochanters pale. Apical 0.3 of hind femur, very base of hind tibia more lightly pigmented. Knees of midleg pale. Legs without scales. Midleg tarsomeres 1–3 with thick subapical setae. Tarsal claws of each leg equal to those of others; equal on each leg, simple. Empodium ( Fig. 4K ) thick, of intermediate length, with 7 multifid branches. Ta1/Ta2: 2.91 (2.76–3.08); Ta3/Ta4: 1.16 (1.18–1.20).

ABDOMEN ( Fig. 4L ). Uniformly medium/dark brown.

Male and immatures

Unknown.

Distribution and biology

This species is known from the female holotype, collected at 395 m a.s.l. in Lençóis municipality in Chapada Diamantina National Park, Bahia, and two female paratypes collected in Santa Catarina. The holotype was collected by the margin of a brook, using a frog-call pan trap playing the call of Bokermannohyla oxente Lugli & Haddad, 2006 , a hylid frog endemic to the locality. The specimens from Santa Catarina were also collected via frog-call, playing the call of another hylid, Boana bischoffi (Boulenger, 1887) . The attraction to frog calls and the serrate mandibles suggest this species feeds on frog blood in nature. Attempts to collect immatures at the brook in Bahia were unsuccessful.

Remarks

Corethrella pindorama sp. nov. belongs to the well-supported rotunda group, established by Borkent (2008). The synapomorphies supporting the group shared by this species include the undivided posterior anepisternum, and wings and legs without patterns of dark pigmentation. The apex of wing vein R 2 basal to the apex of M 1, the elongate coronal suture, wing veins without setae, flagellomeres I–IV elongate and an elongate palpus segment III suggest C. pindorama is sister to C. rotunda Borkent, 2008 , or sister to C. rotunda plus the remaining species of the group. Corethrella pindorama can be promptly differentiated from C. rotunda by its elongate coronal suture, patterned thorax, pale halter and the thick, multifid empodium. The empodium is similar to those found in C. xokleng and C. yucuman .

Figures

Fig. 4. Corethrella pindorama sp. nov., female adult, holotype (MZUSP). A. Head in anterior view. B. Cranial setae, anterior and posterior views, and clypeus in anterior view. C. Left palpus, lateral view. D. Flagellomeres, lateral view. E. Flagellomeres and pedicel, lateral view. F. Thorax and legs, lateral view. G. Detail of thorax, lateral view. H. Thoracic setae, lateral view. I. Wing veins. J. Wing. K. Hind leg claw and empodium, lateral view. L. Abdomen, dorsal view. Scale bars: 0.1 mm.