Pseudastylopsis Dillon, 1956

Pseudastylopsis Dillon, 1956 View in CoL

Pseudastylopsis Dillon, 1956b: 220 View in CoL .

Remarks. – According to Dillon (1956b): “Moderately small or moderate-sized, subconvex forms, with prothorax quite cylindrical … eyes separated above by twice the width of an upper lobe, lower lobe subequal to gena in height. Pronotum quite cylindrical, sides subparallel, widest just behind middle, not quite half again as wide as long, lateral

Reviewer:

Antonio Santos-Silva (Museu de Zoologia, Universidade de São Paulo, Brazil) - Orcid: https://orcid.org/0000-0001-7128-1418

tubercles small, not or scarcely equaling median discal tubercle in this respect;disk entirely,distinctlypunctate,with five or seventubercles,the central one strongly prominent. Elytra distinctly punctate to apices, usually with prominent costae, always tuberculate or with scattered, serrate tufts; apices not prolonged, subtruncate or separately round. Prosternal process one-sixth as broad as a procoxal cavity; mesosternal process about two-thirds as broad as a mesocoxal cavity, expanded apically … Antennae slightly longer than body in female, one-fourth longer in male; scape extending to just behind middle of pronotum, prominent at apex on ventral side; third segment at least one-fifth longer than first; fourth at least subequal to first …” Dillon (1956b) included two species: P. nebulosa (Horn, 1880) , the type species, and P. pini (Schaeffer, 1905) . Linsley & Chemsak (1995) reported the prosternal process as “about one-sixth to one-third as broad as coxal cavities” and mesoventral process “about two-thirds as broad as coxal cavities.” However, Chemsak & Linsley (1986) described P. squamosa and reported the prosternal process as “almost one-half as broad as coxal cavities” and the mesoventralprocess “aboutas broadas coxalcavities,” and Linsley & Chemsak (1995) described P. nelsoni nelsoni and P. nelsoni australis , and described the prosternal process in the former as “about half as broad as coxal cavity” and the mesoventral process “about two-thirds as broad as coxal cavity.” Although the prosternal and mesoventral processes were not described in P. nelsoniaustralis , they reportedthat this subspecies is similar to P.nelsoninelsoni . Therefore, it is expectedthat the processes are as in P.n. nelsoni . In the specimen of P. nebulosa we examined, the narrowest area of the prosternal process is about one-fourth the width of the procoxal cavity,and not one-sixth as reported in the original description of Pseudastylopsis .

Dillon (1956a) separated Pseudastylopsis (written as Pseudostylopsis ) from Leptostylus in the alternative of couplet “1”: “Prosternal process one-half or more than half as wide as procoxal cavity,” leading to Leptostylus ; and “Prosternal process less than half as wide as a procoxal cavity,” leading to Pseudastylopsis . However, the width of the prosternal process in the species currently included in these two genera is very variable, making the alternative of couplet not useful. Therefore, the separation of Pseudastylopsis from Leptostylus is problematic.

Finally, Pérez–Flores & Santos-Silva (2021) described Pseudastylopsis albus from Mexico and described the prosternal process “distinctly wide centrally, with its narrowest area about as wide as 1/3 of procoxal cavity; mesoventral process gradually narrowed toward its posterior third,then widened, with its narrowest area about as wide as 1/2 of mesocoxal cavity”.