Downeshelea casimirensis, Santarém & Borkent & Spinelli & Felippe-Bauer, 2018

Santarém, Maria Clara Alves, Borkent, Art, Spinelli, Gustavo & Felippe-Bauer, Maria Luiza, 2018, New Neotropical species of Downeshelea Wirth and Grogan and redescription of D. multilineata (Lutz) (Diptera: Ceratopogonidae), Journal of Natural History (J. Nat. Hist.) 52 (9 - 10), pp. 509-540 : 517-518

Downeshelea casimirensis sp. nov.

( Figures 2a–d , 8c–e , 10 )

Diagnosis

Male. The only species of Downeshelea in the Americas with the following combination of features: gonostylus 0.81 length of gonocoxite; parameres fused for 0.19 of total length; stem straight, gradually swollen to apex; distal portion strongly curved ( Figure 8e ); aedeagus subtriangular, heavily sclerotised laterally on proximal 2/3, with a pair of submedian, longitudinal sclerotised stripes and oval areas, basal arch V-shaped, extending to 0.56 of total length ( Figure 8d ).

Female. Unknown.

Description

Male. Head. Eyes slightly contiguous in lower area; antennal ratio 0.91 ( Figure 2c ); palpal ratio 2.0 ( Figure 2b ).

Thorax. Brown, without definite pattern in slide-mounted specimens. Wing ( Figure 2a ) with greyish spot over CuA 2 extending into cua 1, anal cell, reaching wing margin; 2 nd radial cell twice longer than 1 st; wing length 0.85 mm; breadth 0.35 mm; costal ratio 0.70. Halter pale brown. Legs ( Figure 2d ) pale brown, hind femur slightly darker subapically. Fore-, hind tarsomere 1 with one basal, one apical spine; midtarsomere 1 with two basal, two apical, four other ventral spines; apical spines of tarsomeres 2–4 of fore-, mid-, hind legs: 1–1–1; 2–2–1; 1–1–1; fore tarsal ratio 2.31, mid tarsal ratio 2.45, hind tarsal ratio 2.14; claws 0.35 length of their respective tarsomere 5.

Abdomen. Dark brown. Terminalia ( Figure 8c ): tergite 9 with quadrate apex, apicolateral process elongate, slender; sternite 9 slightly concave anteriorly, posterior margin with large convex median lobe with blunt tip bearing 3 long setae. Gonocoxite 2.41 times longer than basal width; gonostylus long, 0.81 length of gonocoxite. Parameres ( Figure 8e ) 1.10 times longer than aedeagus, fused for 0.19 of total length; knob flattened; stem straight, gradually swollen to apex; distal portion strongly curved, 0.53 of total length. Aedeagus ( Figure 8d ) subtriangular, heavily sclerotised laterally on proximal 2/3, basal arch V-shaped, extending to 0.56 of total length with pair of submedian, longitudinal sclerotised stripes and oval areas; distal portion with a deep mesal excavation terminating in two short, slender, sclerotised, slightly serrate processes with pointed tip.

Female. Unknown.

Specimens examined

Holotype male adult, labeled ‘ Holotype Downeshelea casimirensis Santarém, Borkent, Spinelli and Felippe-Bauer , BRAZIL, Rio de Janeiro, Casimiro de Abreu, Union Biological Reserve (22° 25′ 35″ S, 42° 2′ 4″ W), 28 April-17 May 2013, Malaise, Biota Diptera Fluminense team cols.’ (CCER).

Distribution and bionomics

This species is restricted to forests in the Brazilian State of Rio de Janeiro (Casimiro de Abreu municipality) ( Figure 10 ).

Etymology

This species is named after the type locality at Casimiro de Abreu , municipality of Rio de Janeiro State .

Figures

Figure 2. Downeshelea casimirensis sp. nov., male. (a) Wing; (b) eye separation, anterior view; (c) head, anterior view; (d) fore, mid, hind legs (top to bottom).

Figure 8. Downeshelea multilineata (Lutz), (a) male terminalia with aedeagus; (b) parameres. Downeshelea casimirensis sp. nov. (c) male terminalia; (d) aedeagus; (e) parameres. Downeshelea costaricensis sp. nov., (f) male terminalia with aedeagus; (g) parameres. Downeshelea eclectica sp. nov., (h) male terminalia with aedeagus; (i) parameres.

Figure 10. Geographic distribution of species in the Downeshelea multilineata species group.