Brachycyrtus amazonensis, Nascimento & Fernandes, 2024

Nascimento, Alexsandra C. & Fernandes, Daniell R. R., 2024, Synopsis of Brachycyrtus Kriechbaumer, 1880 (Hymenoptera: Ichneumonidae: Brachycyrtinae) from Brazil, with description of two new species, Zootaxa 5430 (1), pp. 1-62 : 17-21

Brachycyrtus amazonensis sp. n.

( Figs. 26 , 27 )

Type material. 6 ♀ ♀ and 2 ♂ ♂. Holotype. BRAZIL, AM [Amazonas]: Rio Preto da Eva / Aprisco Pasárgada / 2°40’10.97” S- 59°39’24.87”W / Suspensa – 80 Plantio / 27.ii.2014 / B. G. Oliveira leg. [collector] (1 ♀, INPA).

Paratypes. AM [Amazonas]: Rio Preto da Eva / Aprisco Pasárgada / 2°42’28.91”S- 59°42’55.82”W / Suspensa – 40 Plantio / 13.ii.2014 (1 ♀, INPA) ; same, except 2°42’21.59”S- 59°42’55.00”W / Suspensa – 60 Plantio / 9.i.2014 (1 ♀, INPA) ; same, except 2°42’21.59”S 59°42’55.00”W / Suspensa – 60 Plantio, 29.xi.2013 / (1 ♀, INPA) ; same, except Suspensa – Borda / 8.i.2014 (1 ♀, INPA) ; same, except Aprisco Pasárgada 2°42’21.59”S- 59°42’55.00”W / Suspensa – 60 Plantio / 13.xi.2013 / B. G. Oliveira leg. [collector] (1 ♂, INPA) ; same, Aprisco Pasárgada / 2º40’10.97”S- 59°39’24.87”W / 14.iii.2014 / B. G. Oliveira leg. [collector] (1 ♂, INPA) .

Non-type material. 1?. BRAZIL. AM [Amazonas]: Rio Preto da Eva / Santa Terezinha / 2°40’16.53” S-59 °39’20.50”W / Suspensa – 60 Plantio / 13.xi.2013 / B. G. Oliveira leg. [collector] (1?, INPA) .

Diagnosis. Brachycyrtus amazonensis sp. n. can be differentiated from other Neotropical Brachycyrtus by the combination of the following characters: propodeum polished, punctate with sparse fine setae and without punctures centrally, area superomedia and area petiolaris confluent, area basalis septate and not laterally delineated, area externa and area spiracularis confluent, anterior transverse carina complete to pleural carina, posterior transverse carina absent, area posteroexterna not anteriorly delineated, lateral longitudinal carina delineated only posteriorly ( Figs. 26D, 26G ; 27E–F ); apex of ovipositor truncated, without teeth and without nodus ( Fig. 26F ).

Description. Holotype female ( Fig. 26 ). Body length 4.25 mm. Head. Antenna length 4.73 mm; 30 flagellomeres clavate slightly, with short and dense setae. Head polished, Occipital carina extending directly to the base of the mandible. Dorsal view ( Fig. 26C ), oblique temple weakly convex; ocelli forming an equilateral triangle; ocellus diameter 0.25 mm; distance between the anterior and posterior ocellus 0.03 mm; shortest distance between the posterior ocellus and the compound eye 0.11 mm; distance between the posterior ocellus 0.07 mm. Front view ( Fig. 26B ), eye height 0.61 mm; eye with a shallow impression opposite antennal insertion. Frons width 0.43 mm, smooth, polished, convex and with fine setae. Face width 0.33 mm, polished, punctate with sparse fine setae and convex. Malar space 0.05 mm. Clypeus 2 times as wide as it is long, truncated apically. Basal mandible width 0.11 mm, bidentate; slender with upper tooth wider than lower, molded apically. Mesosoma. Dorsal view ( Fig. 28E ), mesoscutum polished and punctate with sparse fine setae; notaulus absents; scuto-scutellar groove broad and shallow, smooth and, not anteriorly delineated by a carina. Scutellum punctate with sparse fine setae, as wide as it is long, moderately convex. Propodeum polished, punctate with sparse fine setae, without punctures centrally; area superomedia and area petiolaris confluent; area basalis septate and not laterally delineated; area externa and area spiracularis confluent, anterior transverse carina complete to pleural carina, posterior transverse carina absent, area posteroexterna not anteriorly delineated, lateral longitudinal carina delineated only posteriorly ( Figs. 28D, 28G ). Lateral view ( Fig. 26A ), propleuron polished with sparse fine setae. Pronotum polished, smooth with sparse setae anteriorly; epomia absent. Mesopleuron polished and smooth; epicnemial carina ascending about middle from the anterior margin of the mesopleuron and ventrally approaching the posterior carina of the sternum; sternaulus absent. Metapleuron polished and smooth with sparse fine setae. Mesosternal region short. Fore, mid, and hind legs, coxae with sparse setae and polished; trochanters with sparse setae and polished; trochantelli with sparse setae and polished; femorae with dense setae and polished; tibiae with dense setae, denticles, and apical fringe; tarsi with dense setae and denticles; simple tarsal claw. Fore leg with an apical tibial spur. Mid leg with two asymmetrical apical tibial spurs. Hind leg with two symmetrical apical tibial spurs. Wings. Fore wing length 3.30 mm; pubescent; region 1cu-a distal to base of M& RS; 2m-cu with two bullae. Hind wing length 1.99 mm; abscissa CU spectral.

Metasoma. Polished, punctate with fine setae. Tergite 1 punctate with sparse setae posteriorly. Tergite 2 without thyridium. Length tergite 1 0.68 mm; basal width tergite 1 0.15 mm; apical width tergite 2 0.21 mm. Length tergite 2 0.53 mm; basal width tergite 2 0.21 mm; apical width tergite 2 0.42 mm. Length tergite 3 0.48 mm; basal width tergite 3 0.43 mm; apical width tergite 3 0.46 mm ( Fig. 28E ). Length ovipositor 0.97 mm; apex of ovipositor truncated, without teeth and without nodus ( Fig. 28F ).

Coloration. Head. Whitish-yellow with area interocellar black, extending over the frons in a central spot in the shape of an equilateral triangle and posteriorly continuous with reddish-yellow occipital spot; flagellum reddish-yellow and apically with 7 flagellomeres dark brown. Mesosoma. Predominantly whitish-yellow with mesoscutum containing three longitudinal bands, dark brown lateral bands, reddish-yellow central band and posteriorly with reddish-yellow scuto-scutellar groove; scutellum centrally dark brown and metanotum centrally reddish-yellow; tegula light-brown; mesopleuron with a light-brown diagonal central band, epicnemium and region external without band; propodeum whitish-yellow, reddish-yellow anterolateral spots near the spiracles; metapleuron whitish-yellow. Fore and mid legs whitish-yellow with extensive infuscated spots on the femurs, tibias and tarsi; hind legs whitish-yellow with reddish-yellow spots on coxa, trochanter, femur, and tibia basally and apically; tibial spur apically reddish-yellow; tarsus with tarsomeres apically reddish-yellow. Wings. Iridescent hyaline; with weakly darkened apices; pterostigma brown. Metasoma. Reddish-yellow, tergite 1 posteriorly whitish-yellow, tergites 2+ with a narrow whitish-yellow band posteriorly.

Male. ( Fig. 29 ). Similar to female, except epomia on pronotum present.

Variation (n=7). Body length 4.1–4.2 mm. Antenna length 4.0– 4.7 mm; 29–30 flagellomeres. Ocellus diameter 0.21–0.25 mm. Front view, eye height 0.50–0.62 mm. Frons width 0.43–0.45. Face width 0.33–0.39 mm. Malar space 0.05–0.06 mm. Basal mandible width 0.08–0.11 mm. Pronotum with epomia present only in males. Fore wing length 3.09–3.30 mm; Hind wing length 1.68–1.99 mm. Length tergite 1 0.65–0.73 mm; basal width tergite 1 0.14–0.15 mm; apical width tergite 1 0.19–0.24 mm. Length tergite 2 0.52–0.59 mm; basal width tergite 2 0.21– 0.24 mm; apical width tergite 2 0.42–0.55 mm. Length tergite 3 0.44–0.49 mm; basal width tergite 3 0.41–0.49 mm; apical width tergite 3 0.46–0.53 mm. Length ovipositor 0.97–1.30 mm. Antenna apically from 5–7 dark-brown flagellomeres. The interocellar area spot can be black. The three longitudinal bands on the mesoscutum can be dark-brown or black; scuto-scutellar groove can be light-brown or reddish-brown; the scutellum can be centrally light-brown and metanotum centrally reddish-yellow or brown; tegula can be whitish-yellow or reddish-yellow. The anterolateral propodeum spots can be brown or dark-brown near the spiracles. Hind legs can have light-brown or brown spots on the coxa and trochanter; light-brown or blackened apical tibial spur. Tergites can be black anterodorsally and with a narrow whitish-yellow band posteriorly and whitish-yellow ventrally. Tergite 1 may have a dorsocentral brown spot and tergites 2 and 3 with a dorsolateral brown spot.

Geographical records. Brazil (Amazonas) ( Fig. 28 ).

Biological note. The host of this species is so far unknown. Specimens of B. amazonensis sp. n. were collected in Citrus orchards using malaise trap.

Etymology. Species name dedicated to the state of Amazonas, where the type material was collected.

Holotype condition. Specimen glued to entomological pin on the lateral part of the mesosoma. With the left hind leg detached.

Discussion. Brachycyrtus amazonensis sp. n. is morphologically similar to B. obelix for having the ocelli forming an equilateral triangle, propodeum polished, area externa and area spiracularis confluent, area basalis septate and not laterally delineated, anterior transverse carina complete to pleural carina, area superomedia confluent with area petiolaris. In B. obelix propodeum coarsely punctate and sparse setae anterolaterally, posterior transverse carina present lateromedially so that the area dentipara is separated from the area posteroexterna, but the area lateralis is confluent with the area coxalis, lateral longitudinal carina anteriorly incomplete extending forward from the area posteroexterna ( Figs. 38D, 38G ). In contrast, in B. amazonensis sp. n. propodeum punctate with sparse fine setae, without punctures centrally, posterior transverse carina absent, area posteroexterna not anteriorly delineated, lateral longitudinal carina delineated only posteriorly ( Figs. 26D, 26G ; 27E, 27F ).

Figures

FIGURE 26A–G. Brachycyrtus amazonensis sp. n., holotype female. (A) habitus; (B) head, frontal view; (C) head, dorsal view; (D) propodeum; dorsal view; (E) body, dorsal view; (F) ovipositor; (G) SEM of propodeum; dorsal view.

FIGURE 27A–F. Brachycyrtus amazonensis sp. n., holotype male. (A) habitus; (B) body, dorsal view; (C) head, frontal view; (D) head, dorsal view; (E) propodeum; dorsal view; (F) SEM of propodeum; dorsal view.

FIGURE 28. Map of geographical records of Brachycyrtus amazonensis sp. n. (Legend: the Brazilian state of Amazonas where the species occurs is highlighted in gray. Blue circle for record and yellow star for type locality).

FIGURE 29A–D. Brachycyrtus convergens Cushman, 1936, holotype female. (A) habitus; (B) head, frontal view; (C) tags. Photos: (A, B, C) Bekah Rogers, (D) Bekah Young.

FIGURE 38A–G. Brachycyrtus obelix Gauld & Ward, 2000, female. (A) Lateral habitus. (B) Head, Frontal view. (C) Head, dorsal view. (D) Propodeum, dorsal view. (E) Body, dorsal view. (F) Ovipositor, lateral view. (G) SEM of propodeum, dorsal view.