Frontinus Stål, 1874

Subgenus Frontinus Stål, 1874

Type species (in original binomen): Frontinus degeeri Stål, 1874 View in CoL , by original monotypy.

= Steirodonopis Scudder, 1875 View in CoL ; type species (in original binomen): Steirodonopis bilobata Scudder, 1875 View in CoL , by original monotypy.

Brief diagnosis. This subgenus most similar to subgenus Posidippus (characters under numbers 1, 3, 4, 5 and 6 from Steirodon s. str. diagnosis) but distinguished from latter subgenus by only one character under number 2: dorsolateral denticulated keels of pronotum very low and almost straight in profile ( Figs 69, 73 View Figs 58–73 ). From Steirodon s. str. and Peucestes , this subgenus distinguished by above-mentioned character, and by same characters as Posidippus .

However, the lower rostral tubercle in this subgenus is very diverse, from almost that as in Posidippus (compare Figs 58 and 68 View Figs 58–73 ) to narrower (approximately as wide as the scape; Fig. 71 View Figs 58–73 ) or to very wide and practically completely covering the apex of the upper tubercle in front; the latter feature is characteristic of S. (F.) bilobatum (Scudder, 1875) and some its relatives.

Composition (in original binomens). Frontinus degeeri Stål, 1874 (described from Surinam; distributed from Venezuela to French Guiana); Steirodonopis bilobata Scudder, 1875 [= Steirodonopis scudderi Brunner, 1915 , synonymized with this species by Emsley (1970)] (described from Peru and Bolivia, respectively; distributed from Trinidad and Colombia to Bolivia and Brazil); Posidippus fastigiosus Brunner-Wattenwyl, 1878 [= Posidippus brunneri Bolivar, 1881, synonymized by Emsley (1970)] (described from Peru and Ecuador, respectively; distributed also in Venezuela, Colombia and Brazil); Posidippus irregulariter-dentatus Brunner-Wattenwyl, 1891 (described from Peru; possibly distributed also in Northern Brazil); Steirodon (Frontinum) sulcatum , S. (F.) rufolineatum , S. (F.) barcanti , S. (F.) sandrae , S. (F.) bilobatoides and S. (F.) robertsorum described by Emsley (1970) from Southern Brazil, Peru (with paratypes from French Guiana), Ecuador, Panama (with paratypes from Costa Rica), Peru and Costa Rica (with paratypes from Panama), respectively; Posidippus tricenarius Piza, 1974 (described from Manaus in Brazil); S. (Posidippum) emsleyi Piza, 1979 (described from southeast Brazil); S. (F.) planifemur sp. nov.; possibly Posidippus rarospinulosus Brunner-Wattenwyl, 1891 (described from Peru; see remarks on this species below, after S. (F.) irregulariterdentatum redescription and comparison).

Also, it is necessary to mention that S. (F.) tricenarium was perhaps mistakenly synonymized with S. (F.) rufolineatum by Cadena-Castañeda (2016), because the latter species has distinct small denticles on the dorsolateral pronotal carinae and a darkened stripe along the tegminal M-Cu area as well as lacks a dark line on the costal tegminal edge, but Piza’s species (judging by the photographs of its holotype in OSF) is with almost smooth keel-like dorsolateral carinae on the pronotum, without any darkened stripe on the tegminal M-Cu area and with a dark line on the proximal part of the costal tegminal edge. The latter line is characteristic of S. (F.) degeeri , but this species differs from S. (F.) tricenarium in more denticulated dorsolateral pronotal carinae.