Zethus (Zethus) flaviventris Hermes

Hermes, Marcel G., 2012, Two new species of eumenine wasps in the genus Zethus Fabricius (Hymenoptera, Vespidae, Eumeninae) from the New World, Zootaxa 3401, pp. 43-48 : 46-47

Zethus (Zethus) flaviventris Hermes , sp. nov.

( Figs 9–15 )

Comments and diagnosis. Zethus flaviventris lacks the ventrolateral crest on T1, and runs into couplet 5 in the Z. heydeni species group identification key ( Bohart & Stange 1965). It is dubious at this couplet whether Z. flaviventris matches one or the other alternatives, since the character combination described therein does not match the specimen in hand. Moreover, the color pattern of this species is unique among the members of this group, with the ventral portion of the body extensively yellow ( Figs 9–15 ). Z. cerceroides also shows a great deal of yellow markings on the body, but still far less than Z. flaviventris , and both species are also distinguishable by structural characters such as the absence of the ventrolateral crest on T1 of the latter. Z. flaviventris differs from Z. felix Zavattari and Z. infelix Zavattari by the incomplete notauli on mesoscutm ( Fig. 12 ) (complete and distinct on the two mentioned species) and by the sculpture of the posterior surface of the propodeum. In Z. felix and Z. infelix , the posterior surface of the propodeum is longitudinally striate and the median carina is obscured, while in Z. flaviventris the striae are oblique and the median carina evident ( Fig. 14 ).

Type material. Holotype, Ƥ ( DZUP), Costa Rica: “ COSTA RICA: Heredia / Estacion Biol La Selva / 10º25'N, 84º0'W, 80m / 12.vi.1996, GAR Melo”.

Description. FEMALE (holotype). Body length 13,3 mm. Coloration. General ground color yellow, with numerous blackish markings ( Figs 9–15 ). Mandibles yellow with inner and outer margins black. Clypeus yellow with a median basal black spot. Frons and vertex black with yellow markings as follows: two interantennal spots; spots between upper and lower lobes of compound eyes; two oblique stripes behind lateral ocelli. Pronotum with dorsal surface black laterally, yellow on humeral portion, black wide stripe behind humerous, and yellow again on its lower most lateral surface. Mesepisternum yellow with black spot beneath tegula. Mesoscutum black with two narrow longitudinal yellow stripes and lateral small yellow spots near tegula. Tegulae yellow. Scutellum black with two large yellow spots. Metanotum ground color black with a large transverse yellow stripe almost covering the entire surface. Propodeum almost entirely yellow, with two large lateral spots on posterior surface and a median black longitudinal stripe along median carina. T1 black dorsally and yellow laterally. T2 almost entirely black, yellow basolaterally and with a transverse yellow apical stripe. T3 and S3-5 blackish with yellow apical stripes. Scape yellow beneath and chestnut above. Flagellum chestnut beneath and blackish on outer surface. Wings hyaline, venation chestnut.

Pilosity. Body entirely covered by short and sparse golden erect setae, which are somewhat longer on lower posterior propodeum surface.

Surface of integument. Clypeus with punctures indicated but shallow; frons, vertex and mesoscutum coarsely punctate with micropunctures evident; pronotum coarsely punctate but micropunctures only faintly indicated to obsolete; mesepisternum coarsely but shallowly punctured; mesoscutum with notauli evident but reduced; scutoscutellar suture crenate; scutellum punctures as on mesoscutum; punctures on metanotum clearly indicated but shallow; metepisternum and lateral surface of propodeum weakly punctate, background reticulate; posterior surface of propodeum with oblique striae from lateral angle to median carina ( Fig. 14 ); T1 and T2 sparsely and moderately punctate, background smooth on base and micropunctate from summit to apex.

Structure. Mandible 4-toothed; clypeus truncate apically and sinuate basally ( Fig. 11 ); frons somewhat raised, with a weak longitudinal crest medially and a transverse weak crest between antennal sockets ( Fig. 11 ); occipital carina evident, simple and running to base of mandibles, not forked laterally but at least with indication of the hypostomal branch, and angled on lower portion near base of mandibles; occipital carina evident and slightly raised, not lamellar; epicnemial carina evident but not complete ( Fig. 10 ), not reaching the pronotum; tegula slightly elongate, outer margin strongly rounded and posterior lobe absent ( Fig. 12 ); submarginal carina raised laterally, lower medially; valvula free posteriorly and quadrate; mid tibiae with two apical spurs; T1 expanded medially toward middle in dorsal view ( Fig. 13 ), slightly raised in profile; T2 and S2 with wide and translucent apical lamella ( Fig. 15 ); S2 somewhat angled between base and its middle portion.

MALE unknown.

Distribution. Costa Rica (known from the type locality only).

Etymology. The name is derived from the Latin where flavi = yellow and ventris = ventral portion, and is descriptive of the extensive yellow ground color of the body.

Figures

FIGURES 9 – 15. Zethus flaviventris sp. nov., Ƥ, holotype. 9, Habitus; 10, Mesosoma, lateral view; 11, Head, frontal view; 12, Pronotum, mesoscutum, scutellum and tegula, dorsal view; 13, T 1, dorsal view; 14, Posrterior surface of propodeum; 15, T 2, dorsal view. Scale bar for fig. 9 = 2 mm, and figs 10 – 15 = 0,5 mm.