Culicoides carbonelli Spinelli & Martinez, 2021

Spinelli, Gustavo R., Ronderos, Maria M. & Díaz, Florentina, 2021, Two new species and new records of Neotropical Culicoides Latreille (Diptera: Ceratopogonidae), Zootaxa 4915 (3), pp. 401-410 : 402-404

Culicoides carbonelli Spinelli & Martinez n. sp.

( Figs. 1–6 )

Diagnosis. The only Neotropical species of the eublepharus species group with the following combination of characters: antennal ratio 1.19; sensilla coeloconica on flagellomeres 1, 8–10; two separated poststigmatic pale spots in cell r 3; cell m 2 with faint pale spot posterior to medial fork and rounded pale spot narrowly separated from wing margin in apex of cell, without pale spot anterior to cubital fork; anal cell with one distal pale spot; macrotrichia present on distal half of wing and in anal cell, absent in base of m 2; two ovoid spermathecae. Male unknown.

Female.

Head ( Fig. 1 ) dark brown. Eyes bare, separated by distance equal to the length of one ommatidia. Flagellum brown; flagellomeres 2–8 vasiform, 9 bottle-shaped, 10–13 elongate, 13 longest; AR 1.19; sensilla coeloconica on flagellomeres 1, 8–10. Palpus ( Fig. 2 ) brown, segment 3 slightly swollen on midportion, with deep subapical pit; PR 2.20; P/H ratio 0.84. Mandible with 11 teeth.

Thorax ( Fig. 3 ). Scutum uniformly dark brown; scutellum slightly paler, damaged, apparently with 3 large, 3 small setae. Legs dark brown; forefemur with subapical pale ring (distal portion of midfemur missing); fore-, hind tibiae with subbasal pale rings (midtibia missing), broad apex of hind tibia pale; hind tibial comb with four spines, first from spur longest. Wing ( Fig. 4 ) length 0.97 mm; width 0.46 mm; CR 0.58; second radial cell, distal third of first radial cell in dark spot; pale spot over r-m crossvein narrowly abutting wing margin; two separated poststigmatic pale spots in r 3, posterior one slightly larger and proximad of anterior one; distal pale spot in r 3 rounded, not abutting anterior wing margin; m 1 with two oval pale spots, distal one separated from wing margin; m 2 with faint pale spot posterior to medial fork, rounded pale spot narrowly separated from wing margin in apex of cell, without pale spot anterior to cubital fork; cua 1 with rounded pale spot abutting wing margin; anal cell with one distal pale spot. Macrotrichia moderately dense on distal half of wing, present also in anal cell, absent in base of m 2. Halter brown.

Abdomen ( Fig. 5 ). Dark brown. Two ovoid, lightly sclerotized, subequal spermathecae with long, slender necks ( Fig. 6 ), measuring 44 by 36 μm, necks 16 μm; rudimentary third, ring present.

Male. Unknown.

Type data and depository. “ Holotype female, Uruguay, Rocha, Bañado Potrero Grande , 10 km N Laguna Negra, 34°65’00’’S, 53º55’00’’W, 16-III-1995, M. E. Martínez ” ( MLPA) .

Distribution. Uruguay, known only from the type-locality, a coastal pond located in southeastern Uruguay. The pond presents fluctuations, with periods flooded with a maximum depth of 1.30 m, and periods when it dries completely. The PH is slightly acidic to neutral (5.0–7.0). The topography of the area is flat, with soils that are difficult to drain; the natural grassland nuanced with palm groves and grasslands is the predominant vegetation, also highlighting extensive areas of native forest ( Verdi 2000).

Etymology. This species is named in memory of the Uruguayan entomologist Carlos Carbonell, who recently died, in recognition of his outstanding contribution to the knowledge of the entomofauna of Uruguay and particularly that of Orthoptera.

Taxonomic discussion. This species belongs to the eublepharus species group. The females of this group includes medium-sized brownish species, and they can be recognized by the sensilla coeloconica present on flagellomeres 1, (6), (7), (8), 9–12, and by the five distal flagellomeres much elongated; wing with second radial cell included in a very dark spot, the cell r 3 with 3 small pale spots, the 2 poststigmatic pale spots sometimes fused, the subapical pale spot in cell r 3 usually transverse, not attaining wing margin, the cell m 2 usually with only one pale spot distal to level of cubital fork; one or 2 pale spots in apex of anal cell, apices of veins dark; and one or two functional spermathecae present.

The antennal sensillar pattern 1, 8–10 exhibited by C. carbonelli is unique within the species included in the eublepharus species group. Within the species included in this group that have two spermathecae, this new species has a wing pattern very similar to that of C. guarani Ronderos & Spinelli, 1994 from northwestern Argentina, particularly for the absence of a pale spot in front of the cubital fork. However, the latter species clearly shows a pale spot in cell m 2 between the cubital fork and the distal spot at wing margin, two distal pale spots in the anal cell, and the macrotrichia extending to the base of cell m 2. The antenna of this new species exhibits the most important extraalar differences in comparison with C. guarani . In the latter species the distal flagellomeres are distinctly smaller (antennal ratio 0.78) and the sensilla coeloconica are present in the flagellomeres 1, 9–12.

Figures

FIGURES 1–6. Culicoides carbonelli n. sp. Holotype female, 1–6. 1 head. 2 palpus. 3 legs. 4 wing. 5 abdomen. 6 detail of spermathecae. Scale bars = 0.05 mm.