Eknomia nigra Santos et Aguiar, 2012

Santos, Bernardo F. & Aguiar, Alexandre P., 2012, Phylogeny and description of Eknomia, a morphologically unusual new genus of Neotropical Cryptinae (Hymenoptera, Ichneumonidae), with three new species, Zootaxa 3237 (1), pp. 35-52 : 43-46

Eknomia nigra Santos et Aguiar , sp. nov.

( Figs 1–4 , 13 )

Description. Holotype female. Fore wing 9.4 mm long. HEAD. Globose, in front view about as wide as high, ventrally not much narrower than dorsally. Mandible densely punctate, with moderately dense and long hairs; MLW 1.29, MWW 1.46; dorsal tooth rhombic, weakly subdivided. Malar space narrow, MSM 0.34. CHW 1.86, clypeus somewhat semicircular, CWW 2.41, nearly entirely flattened, centrally very slightly concave. Supraclypeal area medially scabriculous. Antenna with 30 flagellomeres. Supra-antennal area mostly polished, strigulate near anterior ocellus, with distinct median carina, ventrally distinctly concave. Occipital carina only weakly raised, mostly uniformly curved, at dorsolateral portion slightly angled.

THORAX. Pronotum glabrate, mostly impunctate, sparsely punctate at collar, along dorsal margin of collar with oblique striation; epomia entirely absent. Mesoscutum 1.17 × as long as wide, glabrate, very scarcely punctate, near posterior apex of notaulus weakly rugulose; notaulus reaching about 0.72 of mesoscutum length, weakly impressed, weakly convergent; scuto-scutellar distinctly carinate. Mesopleuron densely covered with short hairs, strongly strigulate; epicnemial carina reaching about 0.8 of distance to subalar ridge, strongly sinuate; sternaulus with strong oblique striation; scrobe shallow; mesopleural suture weakly carinate along entire length. Median portion of postpectal carina strong, moderately long, distinctly arched forwards. Propodeal furrow very narrow and moderately deep, distinctly carinate. Metapleuron moderately punctate, its upper division carinate; juxtacoxal carina represented by very short ridges. Hind coxa scarcely punctate.

PROPODEUM. 1.30 × as long as wide, sparsely pilose, entirely strigulate; on anterior portion, each strigulation strongly curved posteriorwards, posteriorly approximately straight ( Fig. 2 ); anterior margin medially straight, laterally with distinct rhombic projections; SWL 2.00; posterior transverse carina entirely absent.

WINGS. Fore wing vein 1-Rs+M distinctly sinuate; limit between crossvein 1m-cu and vein 1-Rs+M more or less apparent; vein 1M+Rs very slightly sinuate; crossvein 1cu-a arising basad 1M+Rs by 0.32 × its own length; vein 2-Cu 0.55 × as long as crossvein 2cu-a, the two veins slightly angled; APH 1.00, cell 1+2Rs pentagonal, slightly wider than long, AWL 1.24; crossvein 3r-m fully spectral; crossveins 2r-m and 3r-m distinctly but weakly convergent, 2r-m slightly longer; vein 3-M slightly longer than 2-M; vein 4-Rs sinuate; vein 4-M mostly nebulous, distinctly arched posteriorwards, distinctly longer than 4-Rs. Hind wing vein M+Cu apically moderately convex; vein 1-Cu much longer than crossvein 1cu-a, HW1C 1.79; vein Cub apical 0.5 nearly straight; vein 2-1A reaching about 0.85 of distance to wing margin.

METASOMA. T1 about 0.40 × as long as T2–8, moderately stout, T1LW 2.38, apex much wider than base, T1WW 2.36, anteriorly approximately cylindrical, posteriorly strongly depressed; glabrate, very scarcely punctate; spiracle at 0.54 of its length, slightly prominent; postpetiole with distinct, elongate dorsal depression, and a more slight lateral depression; dorsolateral carina only faintly suggested near spiracle; ventrolateral carina weak. T2 short, T2LW 0.73, apex moderately wider than base, T2WW 1.68; thyridium slightly wider than long. OST 0.72; ovipositor very stout, densely punctate; dorsal valve with a dorsal flange over nodus, giving ovipositor apex somewhat rounded, blunt aspect; ventral valve with moderate swelling, apically with 13 teeth.

Color ( Figs 1–3 ). Head black; thorax mostly black, propodeum and metapleuron light orange; metasoma mostly black and whitish. Head: black; labrum and dorsal mark at basal portion of mandible, whitish; maxillary palpi basally and apically blackish, medially whitish; labial palpi brownish; pedicel and flagellum dark brown (134,091,055), f5–10, white, f11–12 dorsally white and f4 with small white mark apically. Mesosoma: black; ventral posterior corner of mesopleuron, triangular posterior mark at mesosternum, lateral portion of propodeal furrow, metapleuron and propodeum except small anterior blackish marks, bright orange (207, 126,039); lateral portion of scutellum with median whitish marks; fore coxa and trochanter basally black, apically dark brown; fore femur brownish orange, dorsally dark brown at basal 0.7; fore tibia whitish, with dark brown ventral longitudinal stripe; fore tarsus basally light brown, blackish towards apex; mid and hind coxae bright orange; mid trochanters and femur dark brown, with orangish apical marks; mid tibia ventrally whitish, dorsally light brown; mid tarsus blackish; hind trochanter marked with orange and dark brown; trochantellus, femur and tibia blackish, tibia with basal 0.2 brownish; basal 0.2 of t1 and apical 0.5 of t5, blackish; remainder of hind tarsus white. Metasoma: black; T1 and S1 bright orange, T1 with narrow blackish lines along dorsolateral carina; T2 with whitish ovoid mark near thyridium; T2–8 with lateral and dorsal whitish stripes, dorsal stripes medially very narrow; S2–6 whitish, with lateral blackish marks; ovipositor sheath brown, ovipositor basally dark orange, apically dark brown.

Male. Fore wing 7.5–9.4 mm long. Very similar to female, except for the following: whitish marks at mandible more extensive; clypeus laterally with whitish spots; maxillary and labial palpi entirely whitish; supraclypeal area with small to large ovoid whitish spot near antennal sockets; antenna with 31–33 flagellomeres; f10–12 white, 13 almost entirely white, 14–15 dorsally white; area just ventral to sternaulus at posterior 0.3 bright orange; fore tarsus almost entirely whitish, t5 blackish; mid tibia whitish with ventral brownish stripe; basal 0.3 of mid t1, whitish; fore tibia and tarsus almost entirely whitish, only with ventral brown stripe at tibia and t5 blackish; hind first trochanter mostly bright orange; basal 0.2 of hind tibia ventrally whitish; hind t5 white; S2–3 with very small brownish lateral marks, S4–7 entirely whitish.

Variation. Fore wing 9.4–10.8 mm long. Antenna with 30–33 flagellomeres; f11 sometimes entirely white; orange mark at mesosternum sometimes small and semicircular; upper division of metapleuron variously marked with black, dark brown and bright orange. Paratypes from Santa Teresa and one from Nova Teutônia with more distinctly whitish marks at mandible; propodeum anteriorly with extensive ovoid blackish marks, area between blackish marks dark brown; all femora and tibiae slightly darker, more extensively blackish; depression at postpetiole less distinct; T1 mostly black; S6 with posterior dark brown stripe; and ovipositor distinctly stouter, with apical flange at dorsal valve more evident ( Fig. 4 ).

Comments. Females of E. nigra , sp. nov. can be distinguished from the other two species by the apex of dorsal valve of ovipositor very stout, somewhat rounded ( Figs 1 , 4 – see also comments for the genus). It is generally more similar to E. propodeator , sp. nov., from which it can be further differentiated by having propodeal crests absent (vs. present); head almost entirely black (vs. with extensive yellow or whitish marks); mesopleuron and mesosternum mostly black (vs. mostly orange); tegula and subalar ridge black (vs. whitish); and mid leg apicad trochanter mostly black (vs. mostly orange). Eknomia rubra , sp. nov. is easily differentiated from E. nigra , sp. nov. by its almost entirely orange head and mesosoma and body generally more slender (see comments below).

Etymology. From the Latin nigrum, meaning “black”; in reference to the mostly black body.

Type material. 5 ♀, 4 ♂♂. Holotype ♀ from BRAZIL: Espírito Santo, Cariacica, Reserva Biológica de Duas Bocas , Pau Amarelo, 27–29.X.2005, yellow pans, Pt. 18, APAguiar et al. ( UFES) . Mounted on triangle point. In good condition . Paratypes: 1 ♂, same data as holotype, except 20–28.X.2005, Malaise trap, Pt. 07 ; 1 ♂, same data except 28.X–5.XI.2005, Pt. 05 . 2 ♀ and 2 ♂ from BRAZIL, Espírito Santo, Santa Teresa, Estação Biológica de Santa Lúcia, trilha principal próxima a riacho [main trail near creek], 10–12.XI.2009, yellow pans, BFSantos ; 1 ♀, same data except trilha principal próxima ao rio [main trail near river], 7–9.XI.2009, MTTavares & BFSantos ( UFES) . 1 ♀ from BRAZIL, Santa Catarina, Nova Teutônia , 27°11’ S, 52°23’ W, 300–500 m, Malaise trap, XII.1967, Fritz Plaumann ( DZUP) ; 1 ♀, same data except XI.1968 ( CNCI)

Distribution record. Atlantic Forest, Brazil, ES ( Fig. 13 ).

Figures

FIGURE 1. Eknomia nigra, sp. nov., holotype, habitus.

FIGURES 2–4. Eknomia nigra, sp. nov. 2, Holotype, dorsal view. 3, Paratype, head, front view. 4, Paratype, ovipositor tip, lateral view.

FIGURE 13. Map with distribution records for Eknomia nigra, sp. nov. (circle), E. rubra, sp. nov. (square) and E. propodeator, sp. nov. (triangle).