Scolebythus bekilyensis, Brazidec, 2024

Brazidec, Manuel, 2024, Sixty-one years later: a second species of Scolebythus Evans (Hymenoptera: Scolebythidae) from southern Madagascar, Zootaxa 5514 (6), pp. 550-558 : 551-554

Scolebythus bekilyensis sp. nov.

urn:lsid:zoobank.org:act:1D9587D2-9957-4C37-90A8-2A48F5DC2F2A

( Figs 1 , 2 )

Etymology. The specific epithet is a reference to the locality where the type specimen was collected.

Type material. Holotype ♀, Madagascar, Androy Region, Bekily : “MADAGASCAR\Bekily\Rég. sud de l’île; MUSÉUM PARIS\ IV.37 \A. SEYRIC; Scolebythus n. sp. \ A. Polaszek, 1995\on loan from Paris; MNHN, Paris\ EY35892 ” ( MNHN) . Holotype condition: specimen almost complete and well preserved, lacking right pedicel and flagellum, right legs, left hind leg.

Diagnosis. Anterior clypeal margin straight in frontal view ( Fig. 2b ); vertex evenly rounded as seen is frontal view ( Figs 1b , 2b ); mesoscutum with even punctures ( Fig. 2c ); forewing with narrow antero-posterior dark band at 1M cell position and wide antero-posterior dark band from apex of 1R1 cell to apex of 2R1 cell ( Fig. 1a ); forewing with 2R1 cell 3.3 × longer than wide ( Fig. 1a ); distal margin of pterostigma evenly rounded and not much protruding in 2R1 cell ( Fig. 1a ); 1M cell more than 2.5 × longer than wide ( Fig. 1a ); posterior metasomal sterna with regularly spaced long setae ( Fig. 1a ).

Differential diagnosis. The new species differs from S. madecassus by the shape of the clypeus, incurved in S. madecassus ( Figs 3c–d : a/a’), the general contour of the vertex, subquadrate with blunt angulation posterodorsally of eyes in S. madecassus ( Figs 3c–d : b/b’), the mesoscutum sculpture, sparse and irregular punctures in S. madecassus ( Figs 3e–f ), the forewing color and pattern, uniformly yellowish in S. madecassus ( Figs 3g –j ), the length of the 2R1 and 1M cells, 4.4 × longer than wide and 2 × longer than wide, respectively, in S. madecassus ( Figs 3g –j : a–b/a’–b’), the shape of the pterostigma, angulate and protruding in marginal 2R1 cell by 1.1 × maximum pterostigmal width in S. madecassus ( Figs 3g –j : c/c’), the metasomal pubescence, posterior metasomal terga with dense patches of setae in S. madecassus ( Figs 3a–b : a–a’).

Description. Female. Color. Head, scape, pedicel and flagellomeres 1–4 light reddish brown; flagellomeres 5–11 brown; palpi yellowish; frons with three dark brown spots around ocelli; mandible reddish brown except dark brown teeth. Mesosoma brown. Metasoma brown, except light brown posterior segments and sting. Forewing with antero-posterior dark band at 1M cell position and antero-posterior dark band from apex of 1R1 cell to apex of 2R1, hyaline in medial area of 1R1 cell, R cell and distally to 2R1 cell. Hind wing hyaline. Legs yellowish. Body pubescence pale yellow to white; wing setae pale yellowish.

Pubescence. Sparse overall. Clypeus, frons and mandible with short decumbent setae; palpi and antennomeres with tiny erect setae, setae shorter than flagellomere width. Gena with long erect setae, setae as long as gena. Dorsum of mesosoma and metasoma with short erect setae; ventrum of mesosoma and metasoma with long erect setae. Wing setae regularly spaced, setae as long as veins diameter.

Measurements. Approximate body length 6.72 mm; head length 1.09 mm; head width 1.09 mm; frons width 0.76 mm; mesosoma length 2.21 mm; metasoma length 3.42 mm; ovipositor length 0.51 mm; forewing length 3.98 mm; hind wing length 2.83 mm.

Structure. Head. Head as long as wide. Mandible length about 2 × proximal mandibular width; quadridentate, teeth decreasing in size ventrodorsally. Clypeus transverse, without defined medial and lateral lobes; anterior margin straight. Malar space very short, length 0.4 × proximal mandibular width. Frons weakly convex, punctate, distance between punctuations about 0.5–0.8 × diameter of anterior ocellus; frons not sculpted otherwise. Compound eye oval, following general contours of head, glabrous, inner margin of eye outcurved; length of eye 0.55 × length of head; supra-ocular line located at level with posterior margin of anterior ocellus. Ocellar triangle compact; distance between posterior ocelli 1.8 × distance between anterior and posterior ocelli; distance between anterior and posterior ocelli equal to diameter of anterior ocellus; distance between compound eye and posterior ocellus 2.1 × distance between posterior ocelli; distance between posterior ocellus and occipital carina 1.9 × distance between posterior ocelli. Gena about as long as width of eye. Vertex evenly rounded. Occipital carina present, complete, extending from top of head and fading near hypostoma. Oral cavity deeply emarginated, forming broad obtuse triangle, length 1.2 × proximal mandibular width; distance between hypostoma and occiput shorter than proximal mandibular width. Palpal formula 6:4; maxillary palpi short, not reaching propleuron. Antennal foramina separated from each other by about their diameter; portion of frons between antennal foramina not elevated. Antenna short, barely reaching posterior margin of pronotum; scape flattened, 2.6 × longer than wide; pedicel longer than wide; flagellomeres longer than wide; flagellomere 1 shorter than flagellomere 2; flagellomere 2–10 subequal in length; flagellomere 11 longest, tapering at apex.

Mesosoma. Pronotum rugose, with collar reduced, transition between dorsal and anterior surfaces of pronotum marked but without carina or sulcus. Propleuron dorsally exposed. Prosternum large, diamond-shaped, anteriorly broadly separating propleura, with distinct longitudinal sulcus, extending on about one third of prosternum length. Mesoscutum evenly punctate, distance between punctures about 2 × diameter of punctures; notauli ill-defined, only present as complete straight shallow darkened line, parallel, posteriorly separated by width of anterior sulcus of mesoscutellum; parapsidal signa ill-defined, only present as complete straight shallow line, anteriorly divergent and posteriorly parallel. Mesoscutellum rugose, anteriorly with narrow straight mesoscuto-scutellar sulcus. Metanotum rugose, much obscured by mesoscutellum, medial region shorter than lateral region. Metapostnotum finely rugose, well defined, forming broad obtuse triangle, slightly expanding into propodeum; slightly depressed in relation to propodeum; medial portion distinctly longer than lateral region. Metapectal-propodeal complex evenly declivitous posteriorly, transition between dorsal and posterior surfaces without carina or sulcus; dorsal and posterior surfaces rugose, with continuous ill-defined median sulcus; propodeal spiracle positioned on lateral surface, distant from metapleuron by about 2 × its diameter.Dorsal proportion of medial lengths of pronotum:mesoscutum:mesoscutellum: metanotum: metapectal-propodeal complex 1.3:6.8:5.9:1:2.5:2.9.

Legs. Protrochanter inserted baso-laterally on procoxa. Tibial spur formula 1:2:?. Tarsal claws simple, edentate.

Forewing. C, Sc+R, M+Cu, A, 1Rs&1M, 1cu-a, Rs+M, 1Cu, 1m-cu, 2M, 2rs-m, 2r-rs&Rs and R1 tubular; intersection of 1Rs&1M anterior, 1Rs shorter than 1M; 1Rs&1M angled at junction with Rs+M; 1Rs intersecting anterior margin almost at right angle. C, R, 1Cu, 1M, 1R1 and 2R1 cells closed; 1M cell rectangular, length 2.5 × maximum width; 1R1 cell length 1.9 × maximum width; 2R1 cell length 3.3 × maximum width. Distal margin of pterostigma evenly rounded; pterostigma protruding within 2R1 cell by about 0.85 × maximum pterostigmal width.

Hind wing. Venation extremely reduced; A vein about 0.5 × length of clavus; costal margin with one straight proximal hamuli and four hook-like distal hamuli; clavus about 0.4 × length of hind wing.

Metasoma. Metasoma elongate and fusiform, longer than head + mesosoma. First metasomal tergum with longitudinal sulcus on anterior surface, transition between anterior and dorsal surface angled; dorsal surface length about 2 × maximum width; posterior margin outcurved. Fifth metasomal tergum simple, without setae or declivity.

Male. Unknown.

Host record. Unknown.

Figures

FIGURE 1. Scolebythus bekilyensis sp. nov., holotype female. a. habitus in lateral view; b. habitus in dorsal view (scale bars = 1 mm).

FIGURE 2. Scolebythus bekilyensis sp. nov., holotype female. a. head in ventral view; b. head in frontal view; c. mesosoma in dorsal view; d. mesosoma in lateral view (scale bars: c, d = 1 mm; a, b = 0.5 mm.

FIGURE 3. Comparison between holotype of Scolebythus bekilyensis sp. nov. (a, c, e, g, i) and holotype of Scolebythus madecassus (b, d, f, h, j). a, b. habitus in lateral view; c, d. line drawing of head in frontal view; e, f. mesosoma in dorsal view; g, h. forewing; i, j. line drawing of forewing (scale bars: a, b, e–j = 1 mm; c, d = 0.5 mm). Images of S. madecassus: Museum of Comparative Zoology, Harvard University; ©President and Fellows of Harvard College.