Diolcogaster flammeus Salgado-Neto & Fernández-Triana sp., 2018

Salgado-Neto, Geraldo, Fernández-Triana, José L., Tavares, Wagner de Souza & Zanuncio, José Cola, 2018, Diolcogaster flammeus sp. nov. from Brazil, a new Microgastrinae wasp (Hymenoptera: Braconidae) of importance in biological control, Revista Brasileira de Entomologia 62 (3), pp. 232-236 : 233-234

Diolcogaster flammeus Salgado-Neto & Fernández-Triana sp. nov.

Description. Diagnosis. This is the only yellow-orange species of the xanthaspis group recorded in the New World thus far. It is possible that more yellow-orange New World species will be discovered in a near future. Female ( Fig. 2 ). Body color entirely yellow to orange yellow, except for dark brown to black on flagellomeres, parts of the scape, and most of the interocellar area, and most of T2–T4 brown. Fore wing with pterostigma and veins brown. Head mostly with striate sculpture on face, frons, gena and vertex; occiput strongly concave and smooth. Mesosoma with anteromesoscutum and scutellar disk rugose-punctate, scutellar disk posteriorly with a keel; propodeum with strong and complete median carina, and additional transverse rugosity on posterior 0.6 of propodeum. Metasoma with T1 slightly widening toward posterior margin and with strong and deep median sulcus running throughout the entire tergite; T2 subtriangular, with relatively strong sulcus delimiting lateral margins and a central area that is slightly raised and delimited laterally by punctures; T3+ smooth; ovipositor sheaths with a few setae on apical 0.3. Metacoxa relatively large, more than half the length of metasoma. Measurements (all in mm). Body length: 3.50. Fore wing length: 3.4. Metacoxa length: 0.96. Metafemur length/width: 1.12/0.31. Metatibia length: 1.22. Length of inner/outer spurs of metatibia: 0.53/0.30. Length of first segment of metatarsus: 0.70. Ovipositor sheath length: 0.25. T1 length: 0.60; T1 width at anterior margin/maximum width 0.20/0.28. T2 length/width at posterior margin: 0.24/0.50. T3 length: 0.36. Length of flagellomeres: F1/F2/F3/F14/F15/F16: 0.26/0.26/0.26/0.15/0.15/0.16.

Male ( Fig. 3 ). Identical to female.

Remarks. Accounting for the new species from Brazil being described in this study, the fauna of the xanthaspis group in the New World now includes four species ( Table 1 ). A key to all New World species is provided below.

1- Body almost entirely yellow to orange-yellow (except for flagellomeres, part of scape and most of interocellar area black, and most of T2–T4 partially brown)... Diolcogaster flammeus Salgado-Neto & Fernández-Triana sp. nov.

- Body mostly to partially dark brown to black... 2

2(1) Female antenna relatively short, as long as fore wing length, and with apical 8–9 flagellomeres with only one placode rank; metacoxa yellow or white-yellow... Diolcogaster iridescens (Cresson, 1865)

- Female antenna longer than fore wing, most flagellomeres with two ranks of placodes; metacoxa black to dark brown... 3

3(2) Second submarginal cell of fore wing triangular and relatively large in size, without defined vein RS + r − m; tergite 2 0.5 × as long as tergite 3.... Diolcogaster bakeri ( Muesebeck, 1922)

- Second submarginal cell of fore wing relatively small in size, slit-like, with short vein RS + r − m; tergite 2 0.6–0.7 × as long as tergite 3... Diolcogaster xanthaspis ( Ashmead, 1900)

Type material. Holotype. Female, “Museu Regional de Entomologia – UFVll , 20 ◦ 45 l S × 42 ◦ 51 l W, 651 m above sea level, 18.V.2011, Wagner de Souza Tavares & José Cola Zanuncio. Holotype locality: Viçosa, Minas Gerais State, Brazil. Holotype label: WAG01.18.05.2011. Host plants: C. spicatus and C. spiralis var. spiralis . Host caterpillar: A. minuta . Paratypes. Same locality as for holotype, five females and five males (all in “Museu Regional de Entomologia – UFV ”, except one female and one male in Canadian National Collection of Insects, Arachnids, and Nematodes ( CNC), Ottawa, Ontario. Labels: Brazil, Minas Gerais, Viçosa-Minas Gerais, 2012, ex. Agarea minuta , coll. G. Salgado-Neto, voucher codes: CNC649489 , CNC649490 ) .

Etymology. The specific epithet, flammeus , comes from Latin, referring to the species color and means “flame”.

Biology. A solitary parasitoid, reared from A. minuta . The information available suggests that it is extremely efficient as a natural enemy. Last larval instar of the parasitoid emerged from A. minuta caterpillars and pupated at the bottom of the plastic container on filter paper in the laboratory. Parasitoid larvae produced a cocoon made of white colored silk. The silk was wrapped around the leaves causing them to fold and become cone-shaped. Parasitized caterpillars survived only long enough to build an extra protection layer for the parasitoids and then died. Caterpillars of different ages were found in a same sampling which suggests ovipositions at different times and overlapping generations.

Distribution. So far only found in Viçosa, Minas Gerais State, Brazil; the municipality is inland, 300 km north of Rio de Janeiro State and west of the coast by 250 km.

Figures

Fig. 2. (A) Female paratype.(B) Head,ventral view.(C) Head, frontal view.(D) Fore and hind wings.(E) Propodeum and metasomal tergites, dorsal view.(F) Mesosoma,dorsal view. (G) Miasma, lateral view.(H) Metasoma, dorsal view of Diolcogaster flammeus sp. nov.(Hymenoptera: Braconidae).

Fig. 3. (A) Male paratype. (B) Head, frontal view. (C) Habitus, dorsal view. (D) Propodeum and metasomal tergite, dorsal view. (E) Fore wing. (F) Metasoma, dorsal view of Diolcogaster flammeus sp. nov. (Hymenoptera:Braconidae).