Corethrella cabocla Feijó, Belchior, Marialva & Pessoa, 2021

Almeida, Jessica Feijó, Picelli, Amanda Maria, Ramires, Adriane Costa, Belchior, Heliana Christy Matos, Marialva, Eric Fabrício, Lima, Hannah Inêz Monteiro Moreira, Ríos-Velásquez, Claudia María & Pessoa, Felipe Arley Costa, 2021, Description of three new species of frog biting midges (Diptera: Corethrellidae) from the Central Brazilian Amazon, European Journal of Taxonomy 778, pp. 148-166 : 151-155

Corethrella cabocla Feijó, Belchior, Marialva & Pessoa sp. nov.

urn:lsid:zoobank.org:act:A37CF95C-DF0F-452C-A9DC-D71F1DA6CE9D

Figs 3–4

Diagnosis

The species can be distinguished from other species of the genus by the following characters the female adult. Four large setae on frons between ventromedial area of ommatidia; clypeus wide, with one or four setae; antenna with flagellomere one and two darker brown while the others are light brown, flagellomere I with four sensilla coeloconica, flagellomere II with one sensillum coeloconicum, flagellomeres VIII– XIII each with a single sensillum coeloconicum; posterior portion of the dorsocentral row with a group of about six elongate setae; wing with apex of R 2 basal to apex of M 2 and with midlength band; abdomen entirely dark brown.

Etymology

The name ‘ cabocla ’ refers to the local name for native Amazonians, feminine gender, a mixture of Amerindian, European and African origins, resulting in a rich heritage and culture.

Material examined

Holotype BRAZIL • ♀ adult; Amazonas State, Manaus, experimental farm of the Universidade Federal do Amazonas FAEXP-UFAM , BR-174, km 38; 02°38′44″ S, 60°03′13″ W; 4 Apr. 2019; H. Lima and A. Ramires leg.; from tropical forest and collected with light trap; ILMD 0001-45 .

Paratypes BRAZIL • 7 ♀♀; same collection data as holotype; ILMD 0001-46-50 • 2 ♀♀; same collection data as holotype; INPA - DIP - 004619 • 2 ♀♀; same collection data as holotype; CEIOC 81296 • 2 ♀♀; same collection data as holotype; CZPB - DP - 008266 , CZPB - DP - 008267 .

Description

Adult female (n = 10) HABITUS. As shown in Fig. 3a.

HEAD ( Fig. 3b ). Laterally expanded in dorsal view. Coronal suture elongate, reaching the area between ventral margin of eye bridge ( Fig. 3c ). Four large setae on frons between ventromedial area of the ommatidia.

ANTENNA ( Fig. 3b ). Darker to light brown, with flagellomeres I and II darker brown, while others are light brown; flagellomere XIII apically bifurcated; sensilla coeloconica distributed according to Table 1.

CLYPEUS ( Fig. 3d ). Wide, with one to four setae. Mandible with small pointed teeth. Palpus light brown; segment lengths: range; mean; 1.5 SD (in µm): 1 –(9.6–16.5; 11,5; 2.12), 2 –(12.4–26.3; 18.4; 3.82), 3– (28.2–37.4; 36.1; 3.5), 4– (16.2–26.7; 21.7; 3.9), 5 –(38.5–48.6; 43.2; 3.61); average width: range; mean; 1.5 SD (in µm): 3– (10.5–17.4; 15.7; 2.74), 4– (8.8–15.7; 12.9; 2.45), 5 –(7.1–15.1; 11.5; 2.74), third palpal segment slightly expanded at midlength.

THORAX. Dark brown with scutum, scutellum medium brown, pale sclerites around base of wing. Posterior portion of dorsocentral row with group of approximately six elongate setae. Prescutal suture short, not extending to dorsocentral row of setae. Anterior anepisternum medium brown, divided diagonally suture, dorsal portion about equal to ventral portion. Posterior anepisternum dark brown, divided by transversal suture, with ventral portion triangular.

WING ( Fig. 3e ; Table 2 ). Apex of R 2 basal to apex of M 2. Anterior margin with differently and discretely pigmented scales, with midlength band, some with darker more basal scales restricted to veins C, R (except R 4), and M; veins with well-developed scales. Halter light brown, lighter than scutellum.

LEGS ( Fig. 4a ). Dark to light brown with slender setae dark brown. Foreleg with dark brown femur to about 3/10 of total light brown structure in apex region, tibia dark brown, approximately 1/10 of the total light brown structure in the base region, tarsomeres 1 to 5 light brown. Midleg with dark brown femur, approximately 3/10 of total light brown apically, tibia light brown from base to about 5/10of total length, other half dark brown, extending to apex, tarsomeres one to five light brown. Hindleg with dark brown femur from base to about 4/10 of length, apical 6/10 light brown, tibia mostly light brown, about apical 2/10 dark brown, tarsomeres 1 to 5 light brown. Tarsal claws equal, inserted apically; each claw without an inner tooth. Empodia ( Fig. 4b ) with similar thickness to apical setae of last tarsomere, longer than average diameter of last tarsomere, with five or six bifid branches.

ABDOMEN. Uniformly dark brown. One ovoid spermatheca. Cercus, equally dark brown ( Fig. 4c ).

Male

Unknown

Distribution

This species is known only from its type locality in the experimental farm of the Universidade Federal do Amazonas FAEXP-UFAM, Manaus, Amazonas State, Brazil.

Taxonomic comments

In the Neotropical key by Borkent (2008) C. cabocla sp. nov. keys to C. lepida Borkent, 2008 . However, it is distinguished from this species by having the antennal flagellomeres dark brown, whereas in C. lepida the antennal flagellomeres I–IV are light brown. Furthermore, C. cabocla sp. nov. has the first flagellomere with four sensilla coeloconica, whereas in C. lepida , the first flagellomere has been described with two sensilla, and the scutum of C. cabocla sp. nov. is dark brown and the scutellum light brown, distinct from C. lepida , in which the color of the scutum and scutellum ranges from medium to light brown. The posterior portion of the dorsocentral thorax in C. cabocla sp. nov. has a group of six elongate setae, whereas in C. lepida five elongate setae are present. The wing of C. cabocla sp. nov. has the apices of R 2 and M 2 at approximately the same level, whereas in C. lepida R 2 and M 1 are nearly at the same level. In C. lepida , a pale brown band has been described on each of tarsomeres 2–4 of the mid and hind leg; tarsomeres are uniformly pigmented in C. cabocla sp. nov. The abdomen of C. cabocla sp. nov. is entirely dark brown, whereas in C. lepida only segments VIII and IX are dark brown. Corethrella caribbeana Borkent, 2008 shares some characteristics with C. cabocla sp. nov. and C. lepida , but C. caribbeana is distinguished from C. cabocla sp. nov. based on several features. In C. caribbeana the flagellomeres I–III are short, whereas in C. cabocla sp. nov. they are elongate. In addition, Corethrella caribbeana has two sensilla distributed on each of flagellomeres IX–XII, whereas in C. cabocla sp. nov. there is only one on each of flagellomeres VIII–XIII. The clypeus of C. caribbeana is squarish, different from that of C. cabocla sp. nov., which is wide. The abdomen of C. caribbeana is light to dark brown, with sternites I–II slightly darker and segment IX dark brown, whereas in C. cabocla sp. nov. the abdomen is entirely dark brown.

The holotype has a set of characteristics that do not fit within the existing species groups of Corethrella ( Borkent 2008) . The only apparent synapomorphy that C. cabocla sp. nov. shares with the groups fulva, appendiculata , brakeleyi and wirthi is found on the posterior dorsocentral region of the thorax, where a group of more than three elongated setae is present. The lack of knowledge of the immature stages and adult males of C. cabocla sp. nov., makes it difficult to associate the new species with a specific species group as defined by Borkent (2008).

We suggest to incorporate the following emendation to the Corethrella . Key by Borkent (2008) to identify adult females of C. cabocla sp. nov.

46. Abdomen uniformly dark brown; cercus dark brown; flagellomere I with four sensilla coeloconica. ...................................................................... C. cabocla Feijó, Belchior, Marialva & Pessoa sp. nov.

– Abdomen medium to dark brown, with segments VIII and IX dark brown; cercus medium brown; flagellomere I with one to two sensilla coeloconica........................................................................ 47

47. Flagellomere I–III elongate; flagellomeres IX–XIII each with only a single sensillum coeloconicum................................................................................................. C. lepida Borkent, 2008

– Flagellomere I–III short; female flagellomeres IX–XII each with two sensilla coeloconica .............. .............................................................................................................. C. caribbeana Borkent, 2008

Figures

Fig. 3.Microphotography of Corethrella cabocla Feijó, Belchior, Marialva & Pessoa sp. nov. ♀, holotype (ILMD 0001 -45).a. Habitus. b. Head. c. Head with coronal suture elongate. d. Clypeus. e. Wing. Scale bars: a = 1mm; b = 100 μm; c–d = 50 μm; e = 200μm.

Fig. 4. Microphotography of Corethrella cabocla. Feijó, Belchior, Marialva & Pessoa sp. nov. ♀, holotype (ILMD 0001–45). a. Legs. b. Tarsal claw with empodium. c. Abdomen. Scale bars: a = 100 μm; b = 10 μm; c = 100μm.

Tables

Table 2. Wing length measurements of the new female species of Corethrella Coquillet, 1902 in mm.

Species	Number	Wing length	Mean	1.5SD	R 1 / Wing length	Mean	1. 5SD
Corethrella cabocla sp. nov.	10	1.1 – 1.25	1.17	0.050	0.587 – 0.70	0.663	0.038
C. ielemdei sp. nov.	10	1.45 – 1.62	1.5	0.062	0.583 – 0.92	0.648	0.130
C. menini sp. nov.	10	1.05 – 1.15	1. 125	0. 038	0.556 – 0.70	0.667	0. 046