Chalcis Fabricius, 1787

Saguiah, Pâmella Machado, Molin, Ana Dal & Tavares, Marcelo Teixeira, 2020, The South American species of Chalcis Fabricius (Hymenoptera: Chalcididae), Zootaxa 4885 (3), pp. 353-383 : 354-355

publication ID	https://doi.org/ 10.11646/zootaxa.4885.3.3
publication LSID	lsid:zoobank.org:pub:4DA945AD-653E-4E8A-A33D-D52E2F9E44D3
DOI	https://doi.org/10.5281/zenodo.4330379
persistent identifier	https://treatment.plazi.org/id/039B87F3-FFC3-BB71-FF6F-F8A7FC19FA71
treatment provided by	Plazi
scientific name	Chalcis Fabricius, 1787
status

Treatment

Chalcis Fabricius, 1787 View in CoL View at ENA

Type species Sphex sispes Linnaeus, 1761 View in CoL , by subsequent designation of Westwood (1839: 65).

Chalcis Fabricius, 1787: 272 View in CoL .

Smiera Spinola, 1811: 147 . Type species Sphex sispes Linnaeus, 1761 View in CoL , by subsequent designation of Curtis (1833: 472). Synonymy by Gahan & Fagan (1923: 31).

Smicra Spinola, 1837: 1 . Unjustified emendation of Smiera .

Diagnosis. Both sexes. Mandibular formula 2:3 or 3:3, the upper tooth larger and longer than the others; mesocoxa with short pubescence dorsolaterally; mesotibial spur at most as long as apical width of mesotibia, occasionally absent. Female. Tarsal claws usually slightly curved ( Figs 1e View FIGURE 1 , 6a View FIGURE 6 ), sometimes falcate ( Fig. 11f View FIGURE 11 ); hypopygium with median portion narrowly extended posteriorly with median portion distinct from the lateral areas ( Figs 2c View FIGURE 2 , 4c View FIGURE 4 , 6d View FIGURE 6 , 9d View FIGURE 9 , 12c View FIGURE 12 , 15e View FIGURE 15 , 20a View FIGURE 20 ), or thickened but only slightly extended posteriorly beyond the adjacent margins ( Fig. 21a View FIGURE 21 ). Male. Tarsal claws almost always bifid apically ( Fig. 10c View FIGURE 10 ); hypopygium enlarged, flat or concave, with distal margin truncate ( Fig. 13b View FIGURE 13 ) to notched ( Figs 7d View FIGURE 7 , 10d View FIGURE 10 , 16c View FIGURE 16 ).

Biology. Few host records known, these as egg-pupal or larval-pupal parasitoids of Stratiomyidae (Diptera) ( Hart 1895; M̹ller 1908; Schremmer 1960; Cowan 1979).

Distribution. Most species on Northern Hemisphere, but present on all continents except Antarctica ( Noyes 2020).

Remarks. Chalcis can be distinguished from other genera of New Word Chalcididae using the key of Bouček (1992). Among Chalcidini , only females of Chalcis and Melanosmicra Ashmead have the posterior margin of the hypopygium medially setose and distinctly produced posteriorly ( Figs 2d View FIGURE 2 , 4c View FIGURE 4 , 6d View FIGURE 6 , 9d View FIGURE 9 , 12c View FIGURE 12 , 15e View FIGURE 15 , 20a View FIGURE 20 ), usually reaching the apex of the gaster. Species of both genera also have mandibles that lack a ventral lamina, the upper tooth longer than the lower teeth (except a few Melanosmicra species in which the lower tooth is the longest), and a relatively long petiole and short gaster ( Figs 3a View FIGURE 3 , 5a View FIGURE 5 ). Species of Chalcis differ from those of Melanosmicra by the female hypopygium having the median portion extended posteriorly as a narrow projection ( Figs 2d View FIGURE 2 , 4c View FIGURE 4 , 6d View FIGURE 6 , 9d View FIGURE 9 , 12c View FIGURE 12 , 15e View FIGURE 15 , 20a View FIGURE 20 ) or with the median portion distinct from the lateral areas, thickened but only slightly extended posteriorly beyond the level of adjacent margins ( Fig. 21a View FIGURE 21 ) (posterior margin angled or bilobed in Melanosmicra ); hypopygium of males comparatively large, flat or concave, and with distal margin truncate ( Fig. 13b View FIGURE 13 ) to notched ( Figs 7d View FIGURE 7 , 10d View FIGURE 10 , 16c View FIGURE 16 ) (hypopygium surface and distal margin convex in Melanosmicra ); mesocoxa with short pubescence on dorsolateral surface (with few long, erect bristles in Melanosmicra ); mesotibial spur absent or when present at most as long as the apical width of the mesotibia (longer than apical width of mesotibia in Melanosmicra ); and metafemur usually without inner basal tooth ventrally or, if present, inner tooth short and triangular ( Fig. 18a View FIGURE 18 ) (almost always spinelike and curved in females of Melanosmicra ). The shape of tarsal claws has also been used to differentiate Chalcis species. In females, the claws have been most commonly described as slightly curved ( Figs 1e View FIGURE 1 , 6a View FIGURE 6 , 8f View FIGURE 8 , 9a View FIGURE 9 , 14f View FIGURE 14 , 15a View FIGURE 15 ) but in some species the claws are falcate ( Figs 3f View FIGURE 3 , 11f View FIGURE 11 ). In males, the tarsal claws are usually pectinate basally and almost always bifid apically ( Figs 7c View FIGURE 7 , 10c View FIGURE 10 ).

In addition to external morphology characters, Delvare (1992) lists the following features of the male genitalia as diagnostic to Chalcis : phallobase with dorsal expansion, emarginate apically, completely open ventrally, ventral frame most often present, median ventral lamina narrow, without incision on each side of the median ventral lamina; aedeagus with dorsal and sometimes ventral expansion. For comparison, in his diagnosis for Melanosmicra , he lists the phallobase closed ventrally at least along half length; ventral frame more or less obsolete or absent; median ventral lamina normal; phallobase emarginate or slightly incised near median ventral lamina; digiti normal, not narrow and not emarginate on outer edge; aedeagus short and rounded at apex.