Neoeremus Karny, 1937

Cadena-Castañeda, Oscar J. & Quintana-Arias, Ronald Fernando, 2024, Studies of Raspy Crickets: The Status of the Wingless American gryllacridines (Orthoptera: Gryllacrididae), Zootaxa 5419 (4), pp. 563-583 : 575-578

Neoeremus Karny, 1937

Description. Medium size (body length 18 mm). Coloration. The only known species is ocher in color, with the posterior margins of the tergites outlined in brown; from the eighth tergite onwards, they are entirely dark brown ( Figs. 8A–D ). Head. Space between antennal sockets 1.5 times wider than the antennal scape; ocelli rounded, small, and diffuse ( Fig. 8C ); maxillary palps elongated, third and fourth segment similar in size, fifth segment a little longer than the previous ones and slightly dilated at the apex; labial palpi robust, the last segment noticeably dilated and with rounded apex ( Fig. 8A ). Thorax. Pronotum narrow and smooth, with quadrangular disc, anterior margin rounded, posterior margin convex in the middle ( Fig. 8B ); lateral lobes rectangular, wider than high, with v-sulcation decided; auditory spiracle below the lower margin of the lateral lobe of the pronotum armed with a conical fold, attached on the mesothorax ( Fig. 8A ). Sternum lobes are rounded and narrow, without prolongations; mesosternum quadrangular with the anterior margin 1.5 wider than the posterior one; metasternum triangular and narrow. Legs. Fore coxa armed with a spine dorsally. Fore and mid femora unarmed; fore and middle tibiae with four medium-size spurs on each ventral margin and one spur on each side of the ventral-apex; hind femur robust, ventrally armed; hind tibia armed with small spines dorsally only, apex with three spurs on each side, being the upper and mid one the longer and similar in length ( Fig. 8A ). Wings. Absent, but with a tiny acute finger projection on lateral margins of meso- and metanotum. Abdomen. Stridulatory apparatus present on the sides of first and second tergites. Ninth tergite slightly produced posteriorly; tenth tergite mostly covered by the ninth tergite, with a median furrow, divided the tergite in two plates with a small denticulation on inner posterior edge of each plate. Cerci almost cylindrical, short, and unmodified. Paraprocts unmodified ( Fig. 8D ). Subgenital plate with a large, simple, straight cylindrical socketed style on each side, posterior margin produced in a plate almost as long as stylli with apex rounded ( Figs. 8D, F ).

Female. Unknown.

Distribution. Mexico, Oaxaca ( Fig. 8E , Map 1 ).

Taxa included. Neoeremus oaxacae ( Hebard, 1932) , type species.

Comments. This genus was established by Karny (1937) without an official description. Karny (1937) mentioned that the two species grouped in Neoeremus ( N. oaxacae ( Hebard, 1932) and N. rivimeridionalis Karny, 1937 ), are similar to Camptonotus , but cannot be grouped in the latter genus, since the spination of the fore and middle tibiae is different. Karny includes this genus in his key to genera, relating it to Melaneremus Karny, 1937 , distinguished by the dorsal spines of its hind tibia, which could not be considered useful characters to differentiate the genus from the other taxa studied by the author.

As noted in previous comments, the first formal description of Neoeremus is provided here, which, due to its morphological characteristics, such as the very robust hind femur, and the prolongation on the posterior margin of the subgenital plate, fits into the tribe Progryllacridini . Only the type species is included; N. rivimeridionalis is placed in a new genus, as it does not meet the characteristics that define Neoeremus . Specimens of an additional species from Guatemala, of which we only have the female, could extend the generic distribution. It is necessary to study males to verify the validity of this possible new species.

Figures

MAP 1. Camptonotus affinis and Neoeremus oaxacae distribution.

FIGURE 8. Neoeremus oaxacae (Hebard, 1932) male holotype. A. Habitus in lateral and, B. dorsal views. C. Frons. D. Terminalia in ventral view. E. Labels. F. Subgenital plate after Hebard (1932). (© J. Weintraub).