Nilothauma werekena sp. nov. Figures 14A-C, 16D

Type material.

Holotype male, slide-mounted: Brazil, Amazonas, Barcelos, Rio Aracá, Foz do Igarapé Cuieiras, #11, 00°19'15"N, 63°16'15"W, 35 m a.s.l., 30.vii-01.viii.2009, light trap, N. Hamada et al. leg. (UFSC). Paratypes: 4 males, slide-mounted, same data as holotype (INPA). 2 males, slide-mounted, same data as previous, except: #9, 00°24'39"N, 63°23'12"W, 69 m a.s.l., 28.vii-06.viii.2009, light trap #3, N. Hamada et al. leg (MZSP).

Etymology.

The specific epithet honours the Werekena indigenous people from the Rio Negro Basin in the Amazon. The name is to be regarded as a noun in apposition.

Diagnostic characters.

The male can be distinguished from its congeners by the combination of: tergite IX with one low, but wide median dorsal protruberance with about 30 strong setae; anal point spatulate; superior volsella covered with microtrichia, fused to median volsella; laterosternite IX with thorn.

Description.

Male imago (n = 5-7, unless otherwise stated). Total length 1.89-2.26, 2.11 mm. Wing length 0.98-1.11, 1.05 mm. Total length/wing length 1.90-2.15, 1.99. Wing length/length of profemur 2.21-2.53, 2.37.

Colouration. Head, thorax, legs and abdomen uniformly brown. Wing membrane without dark markings.

Antenna. AR = 0.32-0.39, 0.35. Thirteenth flagellomere 230-274, 260 µm long.

Head. Temporal setae 7-8, 7 in single row. Clypeus with 10-14, 12 setae. Tentorium 47-75, 65 µm long, maximum width 12-20, 17 µm . Stipes 80-117, 100 (4) µm long. Palp segment lengths (in µm): 20-32, 27; 22-27, 25; 65-85, 72; 95-125, 110; 87-132, 115. Third palpomere with 2-5, 4 sensilla clavata subapically, longest 12-15, 14 µm long. Fifth palpomere/third palpomere 1.21-1.75, 1.54.

Thorax. Dorsocentrals 6-8, 7 in single row, acrostichals 10-14, 12, prealars 2. Scutellum with 2 setae.

Wing. VR = 1.21-1.32, 1.27. Brachiolum with 1 seta, R with 11-12, 11 setae, R1 with 5-8, 7 setae, R4+5 with 11-17, 15 setae, remaining veins bare.

Legs. Spur of fore tibia 39-44, 42 µm long including 15-20, 17 µm long scale. Mid-tibia with 1 spur, 20-25, 22 µm long; hind tibia with 2 spurs, 20-25, 23 and 28-31, 30 µm long. Combs of mid-tibia 17-19, 18 µm long, of hind tibia 18-21, 19 µm long. Width at apex of fore tibia 29-39, 34 µm, of mid-tibia 34-39, 37 µm, of hind tibia 34-44, 39 µm . Lengths and proportions of legs as in Table 12.

Hypopygium (Fig. 14A-C). Tergite IX without dorsal lobe(s), with low, but wide median dorsal protruberance with 29-32, 31 strong, clustered median setae; posterior margin rounded to subrectangular, with 8-11, 9 weak setae to each side of base of anal point. Anal point spatulate, 37-47, 40 µm long, maximum width 5-10, 7 µm . Tergite bands not continuous. Laterosternite IX with 1-2, 1 seta; with anterolateral thorn. Phallapodeme 40-50, 45 µm long; transverse sternapodeme 15-25, 20 µm long. Gonocoxite 62-82, 72 µm long. Inferior volsella strongly curved, 22-30, 27 µm long, 5-8, 6 µm wide medially, with microtrichia and 3 strong, simple setae apically. Superior volsella tongue-shaped to slightly pediform, 32-40, 37 µm long, 15-25, 20 µm wide at base, densely covered with microtrichia. Median volsella fused to superior volsella, consisting of 2-3, 2 small tubercles, each bearing single, long seta. Gonostylus 70-100, 90 µm long, basal half curved, distal half straight. HR = 0.63-0.96, 0.83. HV = 2.26-2.70, 2.34.

Female adult and immatures.

Unknown.

Distribution

(Fig. 16D). Known from Barcelos (Amazonas State), in the Brazilian Amazon.