A new species-group of Dissomphalus (Hymenoptera: Bethylidae), with description of thirteen new species Alencar, I. D. C. C. Azevedo, C. O. Zootaxa 2008 2008-08-18 1851 1 1 28 Evans 1969 [151,297,1693,1719] Insecta Bethylidae Dissomphalus GBIF Animalia Hymenoptera 1 2 Arthropoda species microstictus   Diagnosis:male. Clypeus with trapezoidal median lobe ( Fig. 2); apex of ventral ramus of aedeagus with latero-apical filament ( Fig. 4). Female: mandible tetradentate with subupper tooth smaller than uppermost one ( Fig. 98); clypeus with median lobe rounded, mid part elevated and thick in frontal view ( Fig. 99).   Comments: the  microstictusspecies-group comprises 14 species:  D. balteus,  D. divaricatus,  D. forceps,  D. incurvatus,  D. osseus,  D. paululus,  D. perparvus,  D. perturbatus,  D. perventriosus,  D. pilus,  D. refertus,  D. signatus, and  D. uncus, in addition to  D. microstictus. The latero-apical filament of the ventral ramus of the aedeagus is proposed as a diagnostic feature for the  microstictusspecies-group rather than only for  D. microstictus. Unlike most of the species-groups in  Dissomphalus, the  microstictusspecies-group is diagnosed by the shape of the genitalia. The large intra- and interspecific variation of the tergal processes in the  D. microstictusspecies-group, varying from absent to conspicuous ( Figs. 3, 12–16, 90), makes this character inadequate as a diagnostic character for species-group level.   Dissomphalus xanthopushas a filament in the ventral ramus, like species in the  microstictusspeciesgroup. But  D. xanthopushas the filament near to the inner margin of the ventral ramus, located in the middle of the ramus (see Fig. 19in Azevedo 1999b), whereas species in the  microstictusspecies-group have the filament near to the outer margin of ventral ramus and located apically in the ramus ( Fig. 4). The mandible of the species of the  microstictusspecies-group can have two or three apical teeth. The number does not vary within each species, but  D. microstictusand  D. perventriosushave specimens with mandible bi- or tridentate. The number of mandibular teeth varies in many other species such as:  D. differensRedighieri & Azevedo,  D. distansRedighieri & Azevedo,  D. infissusEvans,  D. laminarisRedighieri & Azevedo,  D. lobicephalusAzevedo,  D. setosusRedighieri & Azevedo, and  D. spissusRedighieri & Azevedo. Futurekeys for  Dissomphalusshould consider this intraspecific variation. The tergal process (having a pit only or a pitted tubercle) also varies within species as discussed above. Some specimens of the  microstictusspecies-group potentially could be misidentified as belonging to the conicusgroup. Members of this species-group have tergal processes with conspicuous pitted tubercles bearing tufts of setae. The same occurs to  D. connubialisEvans, as discussed by Redighieri & Azevedo (2006), when they suggest  D. connubialisas a possible member of the conicusspecies-group. Every species included in the conicusgroup has tuft densely setose justifying  D. connubialisas a member of this group. Differing from the conicusgroup, the species in the  microstictusspecies-group have tubercle always with none or only with few short setae mesad. Besides, many specimens of the species of the  microstictusspecies-group have the tubercle with a pit on top and the anterior margin of the depression with conspicuous setae resembling the specimens of the  setosusspecies-group. Furthermore, at least some specimens of  D. balteus,  D. perventriosus,  D. microstictus, and  D. divaricatushave tergal process completely absent. Such intraspecific variation is also found within others groups and species, such as  D. incomptusEvansand  D. microtuberculatusAzevedo. The metasomal tergites of the specimens studied here seem to have a characteristic pattern: a w-area in the middle of each tergite is lighter or darker than laterally ( Fig. 16). This pattern is better seen in specimens without tergal process, as well as in specimens with lighter color on the metasoma. The paramere of the species analyzed in this study is bilaminar basally ( Fig. 89), but this condition has also been observed for other  Dissomphalusspecies, such as  D. coronatusAlencar & Azevedo,  D. excellensRedighiri & Azevedo,  D. fungosusEvansand  D. napoEvans.   Etymology: refers to the oldest species of this group.   Distribution: Panama, Venezuela, Trinidad and Tobago, Brazil, Ecuador, Peru, Boliviaand Argentina.