Nealiolus chayohtli Wengrat & Shimbori, 2020

Shimbori, Eduardo M., Wengrat, Ana P. G. S., Savaris, Marcoandre, Galvão, William B., Nanini, Frederico, Garcia, Sarah S. P. & Corrêa, Alberto S., 2020, Two new species of Nealiolus Mason (Hymenoptera, Braconidae, Brachistinae) reared from pest weevils (Coleoptera, Curculionidae), Zootaxa 4729 (1), pp. 116-126 : 119-122

Nealiolus chayohtli Wengrat & Shimbori sp. n.

( Figs 1‒8 , 17 )

Material Examined. Holotype, ♀ “ BRAZIL: São Paulo, Amparo, bairro Boa Vereda , MSWP 09 , 22º44.713’S 46º43.348’W, 789 m, 07 Mar 2018, reared from pupae of Phymatophosus cf. squameus in stems of Sechium edule (Jacq.) Sw. (chuchu), M. Souza-Filho, L. R. F. Louzeiro, J.A. Azevedo-Filho, M. Savaris. ” Point mounted, deposited at DCBU ( DCBU #370877 ) . Paratypes: 6 ♀ s and 1 ♂ same data as holotype ; 5 ♀ s and 4 ♂ s same data as holotype, except date “ 06.XII.2018 ” (one ♀ and one ♂ at DCBU: #370878, #370879; others at ESALQ) .

Description of ♀. Body length 2.7‒3.5 mm; fore wing length 2.7‒3.4 mm; antenna length 2.6‒3.2 mm.

Color ( Figs 1, 2 ). Body black; mandibles yellowish brown; palpi yellowish brown. Antenna dark brown lighter basally, scape darker than pedicel and flagellum. Fore legs yellow except coxa black with portion apical yellowish brown and trochanter and trochantellus dark brown; mid legs coxa black portion apical yellowish brown, trochanter and trochantellus yellowish brown, femur and tibia dark brown with yellowish brown apex, tarsus yellowish brown; hind legs coxa black with portion apical yellow, trochanter and trochantellus and yellowish brown, femur, tibia dark and tarsus (face ventral yellowish brown dark brown. Wings hyaline, veins and stigma dark brown; tegula black; ovipositor and ovipositor sheaths brown.

Head ( Fig. 3 ). Covered with white setae. Transverse in frontal view, face 2.3‒2.7 × wider than high; distance be- tween tentorial pits 1.3‒1.4 × height of clypeus; eye height 0.6‒0.7 × face width; clypeus transverse, about 2.3‒2.5 × wider than high; ventral margin weakly convex and without median tooth but with minute obtuse angulation at level of tentorial pits. Face punctate, clypeus transverse mostly polished with sparse punctation; mid-longitudinal carina extending from between antennal sockets just to reach upper part of face; gena, temples and vertex smooth, vertex, frons smooth and distinctly excavated. Transverse in dorsal view, about 1.8‒2.0 × wider than long; eye 1.2‒1.4 × longer than temple; OOL 3.0‒4.0 × OD, POL 0.6‒0.7 × OOL; ocellar triangle with a deep central pit. Antenna with 29‒31 antennomeres, second flagellomere 0.86‒0.95 × longer than first. Scape as long as wide.

Mesosoma . Covered with white setae. Pronotum crenulate, with some transverse carina anteriorly and a few longitudinal carina posteriorly. Mesonotum mostly smooth with punctation; notauli deeply and strongly foveolate, converging posteriorly in a strongly rugose area; median lobe of mesoscutum distinctly higher than lateral lobes, weakly rugose and bordered by carina just posteriorly; scutellar sulcus with median carina, smooth otherwise and lateral carina only weakly impressed; mesoscutellar trough mostly smooth weakly punctate and few crenulae near scutellum. Mesopleuron smooth glabrous with distinct and crenulate sternaulus. Metanotum mostly smooth, medially with subtriangular fovea with one strong median carina and with carinae lateral and foveolate. Propodeum ( Fig. 4 ) strongly carinate over a rather punctate surface; areola distinct and pentagonal, short middle carina, meeting a diagonal carina at mid-length; areas defined by anterior transverse carinae with rugae and posterior transverse carinae complete cutting the areola, straight and sinuous in the middle of the areola.

Legs. Inner spur of hind tibia about 0.3‒0.4 × longer than basitarsus, inner and outer spurs sub-equal; hind fe- mur 3.7‒4.0 × longer than wide ( Figs 1, 2 ).

Wings. Fore wing ( Fig. 5 ): vein r/2RS = 0.4‒0.5; r/(RS+M)b =0.7‒0.9; stigma length/height = 2.6‒3.1; R1/ stigma length; = 1.1‒1.2; veins 1a and 2a present. Hind wing: M+CU/1M = 2.6‒2.7; 1M/r-m = 0.8‒0.9.

Metasoma ( Fig. 6 ). Covered with white setae, except medial area of T2. T1 distinctly widening apically, apical width 1.5‒1.6 × its length and 1.6‒1.7 × longer than basal width just basal to basal expansions; dorsal carina strong and complete. T1 and T2 mostly longitudinally striate-rugose, except medially on T2; T3 mostly smooth and polished with fine concentric striations basally. Ovipositor length 1.9‒2.4 × longer than metasoma.

Male. Body length 2.4‒3.1 mm; Antenna 2.2‒3.0 mm; fore wing length 2.5‒3.1 mm. Very similar to female, ex- cept: eyes relatively smaller, nearly as long as temple in dorsal view, and ocelli larger (OOL/OD = 1.9‒2.4); petiole narrower, about 1.4 × longer than its apical width; body (head, mesosoma and metasoma) black, except for antenna yellowish brown with apical third darker, and legs brown and yellowish brown, some specimens with T2 dark brown and T3 dark brown with posterior margin light brown.

Diagnosis. The new species is similar to N. auriculatus in having a dark tegula, body black and ovipositor about 2.2 × longer than metasoma. It differs from N. auriculatus in having antenna with 29‒31 antennomeres (27 in N. auriculatus ), scape about as long as wide (2 × longer than wide in N. auriculatus ) and scutellar sulcus with median carina, lateral carina only weakly impressed (with several lateral carina in N. auriculatus ).

Comments. The DNA barcode sequences were compared with public and private records on Barcode of Life Database (BOLD) and GenBank. The two sequences obtained for the new species are identical, and do not match any of the sequences available in the databases ( Fig. 18 ; Table 1 ). GenBank accession numbers: MN178123 ; MN178124 .

Distribution. Neotropical. Known only from Type locality at Amparo, São Paulo, Brazil ( Fig. 17 ).

Natural history. All specimens in the type series are associated with the weevil Phymatophosus squameus Faust, 1896 ( Coleoptera , Curculionidae , Cryptorhynchinae ) in stems of chayote – Sechium edule (Jacq.) Swartz (Cucurbitaceae) . The larvae of P. squameus pupate inside old stems of chayote. We opened stems with signs of infestation by the weevil in the laboratory and observed several pupal chambers, along adults and larvae of the weevil. Many pupal chambers were parasitised by N. chayohtli sp. n. ( Fig. 7 ). The larva of the parasitoid kills the host just after the host larvae finishes the construction of the pupal chamber, and weaving of a silk cocoon within the chamber ( Fig. 8 ), and the adult wasp emerges by chewing an exit hole in the stem.

Etymology. The species name is the Nahuati language (i.e. Aztec) word for chayote, from which the Spanish name derived, meaning ‘prickly squash’.

Figures

FIGURE 17. Distribution map for new species of Nealiolus from Brazil: (★) Type locality of N. chayohtli Wengrat & Shimbori sp. n., Amparo, São Paulo. (■) Type locality N. jaboticaba Shimbori & Wengrat sp. n., Piracicaba, São Paulo.

FIGURE 18. Bayesian phylogenetic tree of COI gene fragment of Nealiolus specimens. Branch lengths are drawn to scale; nodal support values below 0.50 were not recorded in the tree; and nodal support values are given as posterior probabilities above the branches in cases with values higher than 0.90. The scale bar corresponds to the expected number of substitutions per site.

FIGURES 1‒8. Nealiolus chayohtli Wengrat & Shimbori sp. n., ♀: 1‒2, habitus, lateral; 3, head, frontal; 4, propodeum, dorsal; 5, fore wing; 6, metasoma, dorsal; 7‒8, pupal chamber of Phymatophosus squameus in stems of Sechium edule (chayote): 7, after adult parasitoid emergence, through circular exit hole; 8, partially opened chamber showing silk cocoon of the parasitoid and the remains (i.e. cephalic capsule) of the last instar host larva.