Distictus terrosus Supeleto & Santos & Aguiar 2019, sp. nov.
Creators: name: Supeleto, Fernanda A.
name: Santos, Bernardo F.
name: Aguiar, Alexandre P.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Ichneumonidae
Distictus
Distictus terrosus

description: Distictus terrosus sp. nov.
urn:lsid:zoobank.org:act: 2DDBF7C0-F7BD-49C0-995C-9254C18A37E5
Figs 14, 16F; Table 1
Etymology
From the Latin ‘ terra ’, meaning ‘earth’ or ‘dirt’, in reference to the general colour of the body.
Material examined
Total of 19 specimens, 12 ♀♀ and 7 ♂♂.
Holotype
BRAZIL • ♀ (mounted on triangle point; apical half of left antenna missing; otherwise in good condition); RS, Pelotas; 31°44′39″ S, 52°13′22″ W; alt. 16 m; 5 Dec. 2003; R.F. Krüger leg.; Malaise; UFES, UFES45302 {0}.
Paratypes
ARGENTINA • 1 ♂; Missiones, San Javier; 12 Nov. 1971; C. Porter [label “ Distictus – Gupta 19_”] leg.; FSCA.
BRAZIL – Paraná State • 1 ♀; Ponta Grossa, Pedreira; 6 Jan. 1944; Coleção F. Justus Jr. leg.; DZUP 3848 [handwritten] {1}. – Santa Catarina State • 1 ♀; Nova Teutônia; 14 Nov. 1952; F. Plaumann leg.; USUC • 1 ♂; ibid.; 28 Nov. 1952; USUC • 1 ♂; ibid.; Nov. 1967; DZUP • 1 ♀; ibid.; Dec. 1967; DZUP {9} • 1 ♀; Nova Teutônia; 27°11′ S, 52°23′ W; 19 Mar. 1947; F. Plaumann leg.; USUC {8} • 1 ♀; ibid.; 14 Mar. 1966; Malaise; CNCI {7} • 1 ♀; ibid.; Jan. 1966; CNCI {2} • 1 ♂; Nova Teutônia; 27°11′ S, 52°23′ W; alt. 300–500 m; 16 Sep. 1937; F. Plaumann leg.; BMNH • 1 ♂; ibid.; 14 Nov. 1958; CNCI • 1 ♀; ibid.; Mar. 1965; CNCI {6} • 3 ♀♀; ibid.; Dec. 1968; CNCI {3, 4, 5} • 1 ♂; ibid.; Dec. 1968; UFES. – São Paulo State • 1 ♀; São Paulo; 1912; Barbiellini leg.; DZUP 18.714 {10}. – Rio Grande do Sul State • 1 ♂; Pelotas; 31°44′39″ S, 52°13′22″ W; alt. 16 m; 5 Dec. 2003; R.F. Krüger leg.; Malaise; UFES, UFES45297.
Description
Female (holotype)
SIZE. Fore wing 13.45 mm long.
HEAD. Clypeus basally moderately convex, at midlength distinctly emarginated, CHW 0.38; median tubercle small, pointed, placed entirely on apical area; apical area moderately long. Mandible densely pilose, MLW 1.23, MWW 0.50. MSM 0.63. Supra-clypeal area moderately pilose, minutely coriarious. Antenna with 30 flagellomeres. Supra-antennal area minutely, faintly coriarious, medially with some rugae, ventrally distinctly concave, with distinct median line.
MESOSOMA. Pronotum sparsely pilose, weakly striate along posterior margin and collar, elsewhere sparsely punctate; epomia moderately stout, distinct and approximately straight only after diverging from pronotal collar, short, ending far from dorsal margin of pronotum. Mesoscutum densely covered with short hairs, densely punctate, mesoscutum 1.20 × as long as wide; notauli medially distinctly convergent, notaulus 0.55 × as long as mesoscutum; scuto-scutellar groove moderately deep, distinctly carinulate. Mesopleuron anteriorly coriarious, posteriorly distinctly lineate; subalar ridge moderately wide, not keeled; epicnemial carina irregular, reaching about 0.85 of distance to subalar ridge; sternaulus moderately deep, posterior 0.4 almost indistinct, with distinct vertical wrinkles; sulcus between sternaulus and scrobe almost indistinct; mesopleural fovea a small pit, otherwise shallow; mesopleural suture distinctly carinulate inside. Metapleuron lineate, densely pilose; juxtacoxal carina vestigial. Hind coxa densely punctate.
PROPODEUM. Sparsely pilose; anterior margin medially very slightly concave; spiracle elongate, SWL 1.69; anterior area anteriorly coriarious-punctate, posteriorly minutely rugulose; posterior area strigate; anterior transverse carina laterally approximately straight, medially distinctly arched forwards; posterior transverse carina represented by slight but distinct sublateral crests.
WINGS. Fore wing vein 1M+Rs anteriorly straight, posteriorly curved; crossvein 1cu-a weakly convex, arising slightly basad of 1M+Rs; crossvein 1m-cu more or less uniformly curved, continuous with 1-Rs+M; vein 1-Rs+M with bulla placed near basal 0.4; vein 2Cua 1.24 × as long as crossvein 2cu-a; 3r-m nebulous, about as long as 2r-m; vein 3-M about as long as 2-M; AWH 1.02, AAW 0.53; areolet not observed (wings folded at 2m-cu); APH 1.25; vein 4-M tubular, approximately straight. Hind wing with 10 hamuli, vein M+Cu apically moderately convex; vein M forming straight angle with vein Cua; HW1C 1.56; vein Cub distinctly convex at apical half, forming straight angle with Cua; vein 2-Rs apically nebulous.
METASOMA. T1LW 1.21, T1WW 3.00; spiracle not prominent, at 0.53 of T1 length; median depression very shallow; lateral depression very shallow; dorsolateral carina represented by blunt and incomplete ridge; ventrolateral carina sharp, complete. T2LW 0.77, T2WW 1.65; thyridium about as wide as long. Tergites 2–8 coriarious-punctate; pilosity progressively denser on posterior tergites and laterally denser than dorsally. Ovipositor slightly downcurved; OST 0.59; dorsal valve moderately punctate; ventral valve distinctly overlapping dorsal valve, its apex with 7 teeth.
COLOUR. Head, mesosoma and metasoma reddish-brown and yellow. Head mostly pale yellow; mandible except small basal mark, large spot on malar space and clypeal borders, supra-clypeal area near toruli and ventral portion of supra-antennal area reddish-brown. Dorsal portion of supra-antennal area, vertex, dorsal 0.25 of gena and occiput black. Orbital band covering almost entire width of gena on its ventral 0.7. Flagellum mostly black; f7–9 entirely black, f6 and 10 mostly black, f11 with small basal white mark; f12–30 ventrally dark brown. Mesosoma reddish-brown; small marks on dorsal and ventral portions of collar, dorsal margin of pronotum, central spot on mesoscutum, tegula, scutellum, postscutellum, subalar ridge, large central mark on mesopleuron, anterior portion of hypoepimeron, dorsal division of metapleuron, dorsal mark covering 0.6 of metapleuron and elongate sublateral marks extending from anterior area of propodeum to its posterior apex pale yellow. Median portion of collar and posterior mark on mesoscutum blackish. Fore and mid tibiae mesally reddish, laterally yellow; fore and mid first trochanter dorsally blackish, fore one ventrally yellow; mid one ventrally orange; fore and mid second trochanters and base of femora orange, remainder of femora dorsally blackish, ventrally yellow; all tibiae and hind tarsus pale yellow; fore and mid tarsi basally pale yellow, blackish towards apex. Hind coxa, trochanters and femur reddish-brown, coxa with dorso-basal yellow spot. Wings hyaline. Metasoma reddish-brown, lighter towards posterior segments, T7–8 deep orange; T1 with small marks just dorsad of spiracle, posteriorly with wide yellow stripe. Sternites lighter than tergites.
VARIATION. Morphometric ranges are shown in Table 1. All examined specimens quite similar to each other, except by the following, slight variations: yellow mark on hypoepimeron sometimes connected to main mesopleural mark, sometimes briefly separated; areolet sometimes distinctly higher than wide, sometimes about as wide as high; one specimen with wrinkling at pronotum and mesopleuron slightly weaker; pronotum sometimes distinctly striate along posterior margin and collar; elongate sublateral yellow marks of propodeum sometimes extending only from posterior margin to anterior tranverse carina; sometimes vein 3-M distinctly shorter than 2-M, rarely longer; sometimes crossvein 1cu-a arising distinctly basad of 1M+Rs; specimen from Ponta Grossa with lateral yellow marks on mesoscutum; two specimens from Nova Teutônia with weak yellow stripe on T1 and with dark marks on tergites; small yellow maks just dorsad of spiracle on T 1 in some cases absent or connected with posterior yellow stripe.
Male
Same overall structure and colour pattern as female, but with the following differences. Smaller, fore wing 8.5–11.5 mm long. Antenna with 32 flagellomeres. Supra-clypeal area entirely yellow, without oblique reddish-brown marks; elongate sublateral yellow marks of propodeum extending from posterior margin to anterior tranverse carina; labial and maxillary palpus pale yellow, brownish towards apex; spiracle of T1 prominent; collar entirely yellow, without interruptions; anterior tranverse carina of propodeum slightly arched forwards, in two cases practically straight; small yellow marks just dorsad of spiracle on T1 absent.
VARIATION.As with the female, males show relatively stable structure and colour patterns. Small variations which might be of some interest are as follows: T1LW 2.62–2.94; T1WW 1.80–2.03. Specimen from Pelotas (RS) with areolet distinctly higher than wide; posterior yellow stripe on T1 sometimes almost indistinct; tergites sometimes with blackish marks; smaller specimen with pronotum polished smooth.
Comments
The new species differs from all other species in the genus by having the mesosoma reddish-brown with yellow marks (Fig. 14C, E) (vs mesosoma black with yellow marks, Figs 9C, 15G). It is also the only species of Distictus with the orbital band interrupted on the temple (Fig. 14E).
Although very different in colour, D. terrosus sp. nov. is most similar in structure to D. mexicanus, from which it differs in 49 features, of which the most important are as follows: fore wing crossvein 1m-cu continuous with vein 1-Rs+M (vs limit between these two veins clearly traceable); fore wing crossvein 1m-cu more or less uniformly curved (vs irregular); anterior transverse carina of propodeum laterally approximately straight, medially distinctly arched forwards (vs slightly arched forwards, medially more distinctly curved); mesopleuron posteriorly distinctly lineate (vs on dorsal posterior corner distinctly lineate); epicnemial carina reaching about 0.85 of distance to subalar ridge (vs almost reaching subalar ridge); fore wing vein 3r-m about as long as 2r-m (vs distinctly shorter than 2r-m); anterior margin of propodeum medially very slightly concave (vs concave); supra-antennal area ventrally distinctly concave (vs ventrally very slightly concave); apical area of clypeus moderately wide (vs narrow); median depression of T1 very shallow (vs absent); sulcus between sternaulus and scrobe almost indistinct (vs distinct); mandible densely pilose (vs sparsely pilose); metapleuron densely pilose (vs moderately pilose).
Distribution records
Brazil (SP, PR, SC, RS), Argentina.
description: Published as part of Supeleto, Fernanda A., Santos, Bernardo F. & Aguiar, Alexandre P., 2019, Revision of Distictus Townes, 1966 (Hymenoptera, Ichneumonidae, Cryptinae), with descriptions of ten new species, pp. 1-64 in European Journal of Taxonomy 542 on pages 47-50, DOI: 10.5852/ejt.2019.542, http://zenodo.org/record/3378752