Curtonotum impunctatum Hendel, 1913

Klymko, John & Marshall, Stephen A., 2011, Systematics of New World Curtonotum Macquart (Diptera: Curtonotidae) 3079, Zootaxa 3079 (1), pp. 1-110 : 58-61

Curtonotum impunctatum Hendel

Figures 13 , 90–98 , and 211

Curtonotum impunctatum Hendel, 1913: 625 .— Wirth, 1975: 78.2 [Neotropical catalogue].

Diagnosis. No New World Curtonotum species , besides those in the C. anus species group and C. curtispinum , have a frons with lateral microtomentose vittae extending to the proclinate setae and a thorax without punctate markings. Curtonotum impunctatum is distinguished from C. curtispinum by the conspicuously spinose costa and more boldly marked wing; and from the C. anus species group by the very dark pigmentation (ground colour is yellow-beige in C. anus species group) and infuscate wings (wings are nearly hyaline in C. anus species group).

Description. Length: 5.1–6.6 mm.

Head: Frons dark brown, slightly paler medially, with green-blue iridescence (visible only from oblique angle), moderate bulge at ventrally and scattered setulae (these pale medially, dark laterally), width 0.9–1.1 times height, slightly wider ventrally, lateral margin narrowly silver microtomentose ventrally (in some specimens this microtomentum extending posterior to major reclinate seta). Ocellar triangle and narrow lateral strip brown-grey microtomentose, microtomentum of ocellar triangle not extending anterior of anterior ocellus, lateral microtomentose strip extending from median occipital sclerite to slightly anterior of proclinate seta. Proclinate seta at ca. one-third sagittal distance between anterior ocellus and ventral margin of frons, anterior to and slightly lateral of major reclinate seta; minor reclinate seta anterior to and medial of major reclinate seta. Face silver microtomentose with dark brown ground colour; vibrissa ca. 2–3 times longer than adjacent subvibrissals. Parafacial and gena moderately broad, former densely silver microtomentose, latter moderately so, ground colour tan and dark brown, respectively, eye height 8.9–13.3 times gena height. Clypeus, palpus, and prementum with medium brown, dark brown and yellow-brown ground colours, respectively, clypeus and prementum silver microtomentose, palpus silver microtrichose. Scape and pedicel with orange-brown ground colour and silver microtomentum, first flagellomere densely silver microtrichose, with orange-brown ground colour on proximal ca. third to half, otherwise medium brown.

Thorax: Grey microtomentose dorsally, silver microtomentose laterally; ground colour dark brown, paler around postpronotal lobe, anterior spiracle and base of wing. Scutum moderately arched, its microtomentum without vittae. Postpronotal lobe with 2 setae, anterior setae ca. 0.6 times length of posterior setae, sometimes third small seta present posterior to these 2 setae; notopleuron without setulae; notopleuron without setulae; scutellum with 2 pairs of marginal setae. Anepisternum with 2 large and 2–3 smaller setae on posterior half; katepisternum with single prominent lateral seta (some specimens with much smaller second setae anterior and dorsal to prominent lateral seta); linear tuft of setulae under fore coxa dark brown. Area below and behind posterior spiracle bare (without fringe of setulae); meron bare.

Legs: Ground colour of coxae and fore and mid femora medium to dark brown, hind femora medium brown, darker apically, tibiae and tarsomeres 1 and 2 tan with dark apices, tarsomeres 3–5 medium to dark brown. Coxae densely silver microtomentose, legs otherwise lightly so. Chaetotaxy black, except for very dense, regularly-spaced transverse rows of setulae anteroventrally on apical half of fore tibia and similar setulae on fore tarsomere 1, these dark brown. Fore femur with 4 posterodorsal setae; ctendial setae 7–8, relatively short and stout; mid femur with 6– 8 anterior setae; hind femur with single subapical dorsal seta. Mid tibia with 2 strong, 1 moderate, and several weak apical ventral setae, moderate setae between 2 strong setae. Row of cuneiform setae completely absent to present along entire anteroventral margin of mid tarsomere 5, completely absent to present on proximal half of anteroventral margin of hind tarsomere 5.

Wing: Alula relatively narrow. Apical half of r 1 and anterior half of adjacent portion of r 2+3 dark brown infuscate, wing otherwise grey infuscate with apical ca. quarter slightly darker.

Abdomen: Dark brown microtomentose, ground colour dark brown. Silver microtomentose lateral maculae covering proximal ca. third, quarter, third, and half of tergites 2–5 respectively, these separate by broad medial vitta.

Male terminalia: Sternite 5 with oval projection basally, apical margin truncate, with invaginate area of desclerotization free of setulae; tergite 6 strongly sclerotized, setulose dorsally; tergite 7 setulose dorsally, relatively long, dorsal length 0.8 times epandrial dorsal length; sternite 6 and 7 bent over and broken along protandrial ridge, sternite 6 well sclerotized left of and weakly sclerotized right of hypandrial ridge, sternite 7 well sclerotized, right portion 7 relatively long, as long as adjacent portion of sternite 6. Epandrium relatively large, setulose, setulae longest dorsally and posteroventrally; surstylus articulating with epandrium, broadly rounded laterally, concave medially, with scattered minute setulae ventrally and dorsally and small obtuse medial projection. Cercus stout, ventral margin flat, posterior margin rounded, longest cercal setulae shorter than longest epandrial setulae. Hypandrium with short, narrow dorsobasal projection, posterior bridge posteriorly and ventrally produced, hypandrial arm distally with large ventrally oriented lobe, lobe with several medially oriented setulae, fused with opposite hypandrial arm distally; postgonite small, rounded, medially oriented, largely obscured by surstylus in posterior profile. Phallapodeme with large posteriorly bulging “fan”, margin opposite fan concave, right and left margin with 2 large, symetrical basal spinose projections; basiphallus well sclerotized basally, stout, distal portion membranous ventrally; distiphallus base relatively short, fused dorsally with basiphallus, apex bent ventrally, laterally flattened, composed of 2 marginally toothed valves, these opening ventrally. Ejaculatory apodeme outside of basiphallus, elongate, with small pores, broadening basally.

Female terminalia: Sternite 5 length 1.1–1.3 times width, sternite 6 length 1.1–1.3 times width. Ovipositor relatively stout. Tergite 7 well sclerotized throughout. Sternite 8 heavily sclerotized apically, apex with slightly concave surface, rounded on profile, with narrow marginal area free of microtrichea. Tergite 8 and sternite 8 weakly sclerotized proximally. Sternite 10 heavily sclerotized and with antrorse spinules medially, proximal margin with slight dorsal bend, profile narrow on proximal half, broader on distal half. Spermatheca elongate, surface rugose/ papillose, apex translucent. Ventral receptacle with slightly bent neck, base of neck very heavily sclerotized and wrinkled, head donut-shaped, duct narrow, with minute transverse wrinkles, inserted into concavity at base of ventral receptacle.

Type material. Hendel’s (1913) type series included 2 syntypes from Peru. Hendel made no indication of a holotype in his publication. One male specimen, labeled typus by Hendel, from this type series has been examined. This specimen is here designated the lectotype. A lectotype has been designated to avoid any confusion surrounding the definition of C. trypetipenne should the original type series prove to be made of more than one species .

Lectotype here designated: ♂: PERU. Huánuco: “Pachitea-M.”, 4.xii.1903 ( SMTD).

Other material examined. ECUADOR. Orellana: ♂, Reserva Etnica Waorani, 1 km S. Onkone Gare Camp, Transect Ent. 0˚39’25.7”S 76˚27’10.8”W, 216.3 m, Trans. 10, Sta. 3, Fogging in terra firme forest, Lot #1753, 4.x. 1996, T.L. Irwin et al., same data except ♂, 2♀, Trans. 1, Sta. 9, Lot # 1669, 30.ix.1996, same data except ♂, ♀, Trans. 1, Sta. 10, Lot # 1670, 30.ix.1996, same data except ♂, 0˚39’26”S 76˚27’11”W, 220 m, Trans. 1, Sta. 4, Lot # 1664, 30.ix.1996, same data except ♂, Trans. 9, Sta. 7, Lot # 1607, 23.vi.1996, same data except ♂, Trans. 9, Sta. 1, Lot # 1601, 23.vi.1996, same data except ♂, Trans. 8, Sta. 1, Lot # 1731, 3.x.1996 (all USNM) ; 2♂, Rio Tiputini , 0˚38.2’S, 76˚8.9’W, 12–26.viii.1999, W.N. Mathis, A. Baptista, M. Kotrba ( USNM) ; ♂, ♀, Yasuni National Park, Yasuni Research Station , 0˚40’50”S 76˚24’2”W, 250 m, 28.iv–8.v.2009, S.A. Marshall , ♂, 28.iv–8.v.2009, M.D. Jackson (all DEBU) . PERU. Pasco: ♀, Upper Rio Pachitea , 21.vii.1920, Cornell University Expedition ( USNM) .

Figures

FIGURES 12–13. 12. Undescribed species in Curtonotum vulpinum species complex on unidentified piece of decomposing material. Yasuni National Park, Orellano, Ecuador. 13. Curtonotum impunctatum Hendel. Yasuni National Park, Orellano, Ecuador.

FIGURES 90–93. Curtonotum impunctatum Hendel. 90. Male terminalia, left lateral. 91. Distiphallus, dorsal. 92. Male sternite 5, ventral. 93. Male terminalia, posterior.

FIGURES 94–98. Curtonotum impunctatum Hendel. 94. Ovipositor, left lateral. 95. Female sternite 8, ventral. 96. Female sternite 10, ventral. 97. Ventral receptacle. 98. Spermatheca.