Pseudochetoneura otongensis, Ševčík, 2012

Ševčík, Jan, 2012, Pseudochetoneura gen. nov., a peculiar new genus from Ecuador, with notes on Chetoneura (Diptera: Keroplatidae), Acta Entomologica Musei Nationalis Pragae 52 (1), pp. 281-288 : 283-284

Pseudochetoneura otongensis sp. nov.

( Figs. 1–5 )

Type material. HOLOTYPE: J, ECUADOR: COTOPAXI: San Francisco de Las Pampas, Otonga Reserve , 17.v.1997, Malaise trap, G. Onore leg. ( SMOC) . PARATYPES: 11 JJ 2 ♀♀, the same data as holotype ( BMNH, JSOC, SMOC).

Description. Coloration. The entire body is dark brown, except antennae and legs, which are slightly lighter.

Male. Body length 3.2 mm. Wing length 3.1 mm. Ratio of wing length to width 2.2.

Head. Two ocelli, the distance between them about their diameter. Compound eyes relatively narrow, twice as high as broad in lateral view. Vertex covered with setae, frons bare. Frons anteriorly narrowing, apically blunt, with a sagittal furrow reaching behind ocelli. Face and clypeus small and narrow, rhomboid, covered with dark setae. Mouthparts strongly reduced. Labellum and labrum rudimentary, in the form of only one small setose oval sclerite, which may represent either labrum or fused labella. Maxillary palpus with a single palpomere of about the same size as the proximal sclerite. Lacinia absent. Palpus with a circular sensilla at the anterodorsal side.

Antenna about 3 times as long as the width of head, with 14 flagellomeres. Flagellomeres relatively short ( Fig. 1 ), cylindrical, laterally only slightly flattened, all covered by fine setae at most as long as the diameter of flagellum. F1 and F14 about as long as wide, F2–F5 and F8–F13 slightly wider than long, F6 and F7 almost twice as wide as long. Flagellomere 14 simple, without any apical process. Scape and pedicel slightly shorter than wide.

Thorax. Scutum with two rows of dorsocentral setae, one row of acrostichals and laterally with numerous prealar and postalar setae. Scutellum rather small, almost as long as wide, dorsally covered with short setae, without long apical bristles. Mediotergite bare, posteriorly slightly protruding, with a narrow indistinct subscutellar membranous area. Laterotergite bare. Antepronotum and proepisternum setose. Anterior spiracle and membranous area around it brownish yellowish, without setae. Anepisternum and the other lateral sclerites bare. Haltere yellowish brown, slightly longer than the first abdominal tergite.

Wing ( Fig. 3 ) hyaline, unmarked but slightly darkened, membrane covered only with microtrichia, without macrotrichia. Radial veins and CuA 2 dark and strong, the other veins lighter. Costa, R 1 and R 5 covered with setae. C produced beyond R 5 to about half the distance between the tips of R 5 and M 1. Vein Sc ending free, apically obsolete, reaching to the level of Rs. R-M fusion short but distinct. Crossvein Rs relatively short and almost vertical. M-Cu connection and basal part of M indistinct. The stem of M-fork long, 4/5 as long as M 1. Cufork distinct, with point of furcation at the base of wing, CuA 1 weaker, CuA 2 strong, distinctly downcurved towards the tip. CuP relatively long and strong, A1 shorter, distally weak.

Legs mostly yellowish brown, covered with dark trichia. Coxae dark brown. Femora laterally flattened, evenly clothed with fine trichia, not longer than maximum width of femur. All tibiae with trichia about as long as tibial diameter, not forming distinct rows, without strong bristles. The apex of fore tibia without distinct tibial organ. Fore tibia with one apical spur, as long as maximum tibial diameter. Two spurs present on both mid and hind tibia, the posteroventral spurs twice as long as anteroventral ones. Relative lengths of femur, tibia and tarsus for particular legs: fore leg – 1: 1.1: 1.7; mid leg – 1.3: 1.6: 2; hind leg – 1.4: 1.8: 2. Tarsal claws simple, almost straight. Empodium filiform.

Abdomen mostly dark brown, distinctly bent downwards. Tergite 1 with a small posterior medial projection. Segment 2 slightly longer than the others. Terminalia ( Figs. 4–5 ). Tergite 9 short, transverse, three times as broad as long ( Fig. 5 ). Cercus 5/6 as long as tergite 9, placed caudally to tergite 9 and partly hidden behind it. Gonocoxites fused only basally by a membranous connection, forming a deep posteroventral excavation ( Fig. 4 ). Gonostylus relatively large (almost as long as gonocoxite), about as long as wide, with rounded apical projection, which is rather broad in lateral view. Aedeagal complex very large and distinct, with long associated apodemes laterally and with a small medial incision at its posterior margin. Its proximal, laterally compressed plate with anterior part circular in lateral view, extending into segment VII.

Female. Similar to male in most respects. Antenna distinctly shorter, only about twice as long as the width of head ( Fig. 2 ). Terminalia with one-segmented cercus, which is circular in lateral view. Sternite VIII divided medially, forming two subtriangular parts in ventral view. Two globular and well sclerotized spermathecae. Spermathecal ducts distinct.

Etymology. The species name refers to the type locality.

Distribution. Neotropical Region ( Ecuador).

Figures

Figs. 1–5. Pseudochetoneura otongensis gen. & sp