Nilothauma jaraguaense, Mendes, Humberto Fonseca & Andersen, Trond, 2009

Mendes, Humberto Fonseca & Andersen, Trond, 2009, Neotropical Nilothauma Kieffer, 1921, with the description of thirteen new species (Diptera: Chironomidae), Zootaxa 2063, pp. 1-45 : 25-26

Nilothauma jaraguaense sp. n.

( Figs 33–36 )

Type material. Holotype male, BRAZIL: São Paulo: Parque Estadual do Jaraguá, 23°27'59''S, 46°45'58''W, 16.xii.2000, F. O. Roque ( MZUSP).

Diagnostic characters. The two dorsal, setose lobes on tergite IX combined with a broadly lanceolate anal point, inferior volsella and gonostylus with apically split setae, and gonostylus nearly parallel-sided will separate the male of N. jaraguaense from all other Nilothauma species.

Etymology. Named after Parque Estadual do Jaraguá.

Male (n = 1). Total length 2.38 mm. Wing length 1.83 mm. Total length / wing length 2.17. Wing length / length of profemur 2.12.

Coloration. Pale with vittae and posterior part of postnotum pale brown; legs and antenna pale yellow.

Head. AR 0.18. Thirteenth flagellomere 91 µm long. Temporal setae 7 in single row including 3 inner verticals, 1 outer vertical, and 2 postorbitals. Frontal tubercles minute. Clypeus with 15 setae. Tentorium and stipes not measurable. Palp segment lengths (in µm): 16, 20, 41, 57, 82. Third palpomere with 2 sensilla clavata subapically, longest 9 µm long. Fifth palpomere / third palpomere 1.44.

Thorax. Dorsocentrals 8 in single row, acrostichals 4, prealars 2. Scutellum with 2 setae.

Wing. VR 1.38. Brachiolum with 1 seta, R with 9 setae, R1 with 6 setae, R4+5 with 13 setae, remaining veins bare.

Legs. Spur of foretibia 50 µm long including 16 µm long scale. Midtibia with 1 spur, 25 µm long; hind tibia with 2 spurs, 23 µm and 34 µm long. Combs of midtibia 14 µm long, of hind tibia 14 µm long. Width at apex of foretibia 35 µm, of midtibia 35 µm, of hind tibia 35 µm. Lengths and proportions of legs as in Table 7.

Abdomen. Tergites with few setae. Segment VIII long, subrectangular, tapering anteriorly.

Hypopygium ( Figs 33–34 ). Tergite IX with subrectangular posterior margin, with 1 submarginal setae to each side of base of anal point; with pair of dorsal lobes submedially, each with about 12 strong setae. Anal point broadly lanceolate, 20 µm long, 16 µm wide. Laterosternite IX with 2 setae. Phalapodeme 45 µm long; transverse sternapodeme lacking. Gonocoxite 68 µm long. Inferior volsella 52 µm long, 7 µm wide subapically, curved with rounded apex, with microtrichia and 7 setae of which all but 1 are split apically. Superior volsella ( Fig. 35 ) 32 µm long, 11 µm wide medially, curved with broadly rounded apex, with microtrichia. Median volsella ( Fig. 36 ) 32 µm long, curved, tapering, with microtrichia and 2 basal and 7 apical to subapical strong setae. Gonostylus 91 µm long, nearly parallel-sided, with 4 apically split setae along inner margin subapically. HR 0.75, HV 2.61.

Female and immatures. Unknown.

Distribution. Known only from the type locality in São Paulo, Brazil.

fe ti ta1 ta2 ta3 ta4 ta5 LR BV SV BR p1 516 332 497 221 203 147 74 1.50 2.08 1.70 2.6 p2 433 322 175 120 64 46 37 0.54 3.48 4.32 4.3 p3 525 461 267 138 120 83 46 0.58 3.24 3.69 4.1

Figures

FIGURES 33 – 36. Nilothauma jaraguaense sp. n., male. 33 — dorsal aspect of hypopygium. 34 — hypopygium with tergite IX and anal point removed, dorsal view left, ventral view right. 35 — superior volsella, dorsal view. 36 — median volsella, dorsal view.