Mischocyttarus (Kappa), de Saussure, 1854

Silveira, Orlando Tobias, 2006, Revision of the subgenus Kappa de Saussure of Mischocyttarus de Saussure (Hym.; Vespidae, Polistinae, Mischocyttarini), Zootaxa 1321 (1), pp. 1-108 : 9

Subgenus Kappa de Saussure, 1854

Kappa de Saussure, 1854 : 200 (as division of subgenus Polybia Lepeletier ); Bequaert, 1933: 112 (as synonym of Mischocyttarus de Saussure ); Richards, 1941: 125 (as subgenus of Mischocyttarus ); 1945: 337; 1978: 289; Snelling, 1983: 275; Carpenter and Day, 1988: 327; Raw, 2000.

Type species: Polybia injucunda de Saussure, 1854 (= Mischocyttarus injucundus ). By subsequent designation of Bequaert (1933).

Diagnosis

Female head in frontal view low and very wide, with more or less distinct triangular outline ( Figs. 8, 9 ); clypeus much wider than high; tentorial pit closer to antennal socket than to eye margin, or at equal distances; antennal sockets separated by a distance larger than their height; interantennal area strongly projecting, its upper portion often reaching frontal region as a continuous slope; occiput usually carinate, margin rarely vestigial or absent; posterior region of the head ventrally with long often quite numerous hairs; pronotum with fovea, carina completely reduced at center, humeral region elongated (rarely shorter), in lateral view the distance between the lateral extremity of pronotal carina and the spiracular lobe is larger than the distance between the latter and the upper posterior angle of the pronotum, posterior margin of pronotum laterally strongly curved, mesopleuron protuberant, upper mesepisternal plate wide and oriented along a fairly horizontal direction ( Fig. 6 ); proepisternum nearly always with the anterior margin strongly raised and reflexed (excepting the species M. laurae sp. n.); propodeum with anterior central region often very protuberant, appearing as a horizontal surface adjacent to metanotum, posterior region adjacent to valve with a well defined lateral concavity, median furrow wide, often shallow behind ( Fig. 100 ); metanotum often distinctly convex; first segment of metasoma usually with the sternum flattened, proximally with a lateral linear prominent and shining edge; pattern of sculpture of the head and mesosoma marked by distinctive granular to coarser punctation; fore leg with the fifth tarsomere usually pale colored. Male genitalia with glabrous elongated digitus ( Fig. 1 ), distal portion of parameres with a tuft of long fine hairs ( Fig. 2 ), aedeagus with the apex broadly round ( Fig. 3 ) (male genitalia unknown in M. laurae sp. n. and some other species); male mandible with three teeth, the first one much longer than the other, linear with the apex flattened and round in contour ( Fig. 5 ). Larva with a single median process in the first abdominal sternum ( Fig. 4 ) (unknown in M. laurae sp. n. and some other species).

Remarks

Among the Mischocyttarus groups that present a pronotal fovea, nearly all Kappa species can be readily distinguished by the shape of the anterior margin of the proepisternum, the margin being strongly raised and reflexed. This peculiar form is otherwise observed only in Megacanthopus , Omega , and a few groups of Haplometrobius , which do not have a pronotal fovea. Defining Kappa on the basis of such a combination of two characters (pronotal fovea present, a plesiomorphy, and proepisternum margin raised and reflexed, homoplastic in other groups) is thus sufficient to differentiate the group as it was known to Richards (1978). The problem of its monophyly then might be a matter of assuming two other characters as synapomorphies (larva with a single abdominal process, and parameres of male genitalia with a distal tuft of hairs). These are reasonable assumptions since the characters, unique in Kappa , were observed in a wide spectrum of groups within the subgenus ( immarginatus , tolensis *, latior , zikaninus *, frontalis , anthracinus *, socialis , imitator , metathoracicus , injucundus , bertonii , funerulus * and villarricanus ; information on the larva unavailable for the species marked with an asterisk). However, the new species M. laurae , here described, does not fit the above definition since in it the proepisternum margin is low, not reflexed. Unfortunately, the male and larva of this species are unknown. But other characters of the female certify its close relationship to remaining species of Kappa , and constitute as well additional evidence of the monophyly of the group as a whole. Mischocyttarus laurae sp. n., differently from most Kappa species, is a very large and rather elongated species, with a long antennal scape (the ratio length/width much more than the usual 2.4; compare Figs. 11 and 12 ). In addition, the ocelli are not positioned as the corners of a low triangle, but other aspects of morphology are typical of the group. The head is low and very wide, with a rather triangular outline in frontal view ( Fig. 8 ). The pronotal carina is completely absent at the center ( Fig. 7 ) (out of Kappa , a similar condition is only found in part of subgenus Phi ). The humeral region is very elongated, and the hind margin of the pronotum laterally is strongly curved ( Fig. 6 ). Correspondingly, the upper mesepisternal plate is wider and less oblique than in other Mischocyttarus groups (a form approached only in species of the M. punctatus group of subgenus Omega ). Finally, the propodeum is typically inflated, the area adjacent to the metanotum appearing as a horizontal surface when seen from above (with similar forms only in Mischocyttarus s. str., and a few Phi species related to M. flavitarsis ).

Figures

FIGURES 8–25. M. laurae sp. n.: 8, 11, female head frontal and dorsal, 16, first metasomal tergum (T1); M. latior: 9, 12, female head frontal and dorsal, 10, male antenna, 14, hind 5th. tarsomere, 19, T1; M. immarginatus: 13, male antenna, 15, hind 5th. tarsomere, 17, T1; M. mirus sp. n.: 18, T1; M. paris sp. n.: 20, mesosoma part dorsal, 21, male antenna, 22, T1, 24, propodeal large punctures; M. tapuya: 23, T1, 25, propodeal large punctures.

FIGURES 1–7. M. immarginatus (male genitalia): 1, digitus, 2, distal aspect of paramere, 3, aedeagus dorsal; M. villarricanus: 4, mature larva; M. injucundus: 5, male mandible; M. laurae sp. n.: 6, 7, mesosoma lateral and dorsal.

FIGURES 97–100. (SEM images) M. imitator: 97, apical aspect of the female clypeus; M. socialis: 98, same as anterior; M. injucundus: 99, propodeum (strongly striate) lateral view, 97, propodeum (moderately striate) dorsal view.