Dasyscelidius Beier, 1954

Cadena-Castañeda, Oscar J., Poveda, Miguel D., Pulido, Sergio Omar & Ariza, Jeison Eduardo García, 2022, Studies on Neotropical Pseudophyllinae: The placement and status of Dasyscelidius species (Orthoptera: Tettigoniidae), Zootaxa 5099 (1), pp. 129-136 : 131-133

Dasyscelidius Beier, 1954

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:6568

New diagnosis. Medium size (20-23 mm) and moderately robust. Coloration. The only species included for this genus are brown with light yellow spots on the body ( Figs. 1 A-C), more noticeable on the legs, and black face (common in several genera of the tribe pleminiini ) ( Fig. 1B ). Head. In front view ovoid, space between the antennal basins, as wide as half of the antennal scapus; fastigium slightly high and narrow; round and small eyes ( Fig. 1B ), in dorsal view, a little bit shorter than the margins of the antennal sockets. Ocelli reduced and diffused; scapus and pedicelus unarmed; maxillary palps moderately elongated ( Figs. 1 A-B). Pronotum slightly granulated, anterior margin projected onto the neck, in the prozone on the side edge only indicated with a longitudinal fold, the metazone not widened ( Fig. 1 ). Wings. Tegmina is almost longer than the pronotum, broadly lanceolate, densely reticulate, with slightly prominent veins and an apex narrowly rounded ( Figs. 1A, C ); hind wings are reduced as small hyaline lobes. Legs slender, fore coxa armed with a conspicuous dorsal spine; all coxae are ventrally unarmed; fore femur not very strong compressed; mid tibia moderately grooved, dorsally unarmed, and all inner genicular lobes armed with a tiny blunt spine. Abdomen cylindrical, without modifications on the segments, epiproctus small and rounded ( Fig. 1D ). Reduced and conical cerci; ovipositor as long as two-thirds of the length of the hind femur, moderately curved and with a sinuous dorsal edge, pointed apex ( Fig. 1E ). Subgenital plate rectangular, wider than long, with a rather prolonged posterior border and with a medial notch ( Fig. 1F ). Male unknown.

Type species. Dasyscelidius atrifrons ( Brunner von Wattenwyl, 1895) by original designation. Herein, the genus is regarded as monotypic.

Distribution. Colombian Andes.

Comparison. This genus is close to others of the tribe pleminiini , with a black face, medium-size and slender. Dasyscelidius has distinguished from the other genera in that the spines on the legs are medium to small in size, in contrast to the related genera of the tribe, which have moderately to well-developed lamellar spines. Dasyscelidius differs from the morphologically similar genus Dasyscelus due to its smaller size (20-23 mm.); absence of spines on the fore and mid tibiae’s dorsal margin; brown body coloration, and densely reticulate venation. In contrast, Dasyscelus groups larger species (25-35 mm.), with spines on the dorsal margin, venation with notorious spaces between the transverse and longitudinal veins, forming medium-sized cells. Additionally, the Dasyscelus species have a coloration from dark brown, passing through grayish green, the pronotum is granular, and sometimes forming conspicuous tubercles, which resemble spines, that surround the pronotal disc as in Dasyscelus dilatatus Brunner von Wattenwyl, 1895

Comments. Dasyscelidius is considered monotypic in this contribution. The female type specimen of D. atrifrons has part of the rectum extracted outwards, protruding between the cerci, and it can be confused with the epiproct at first sight ( Figs. 1 D-E). The exact locality of the species is unknown since, in its description, it was only mentioned that it was collected from Colombia ( Brunner von Wattenwyl, 1895). Recently, iNaturalist observations (https://www.inaturalist.org/observations/70049414, https://www.inaturalist.org/observations/67625294) and an examined female from Bogotá (deposited in CAUD, and agree with type description and measurements), being inhabitants of the Eastern Hills, where they cohabit with an undescribed genus and species, superficially very similar, although belonging to the tribe Platyphyllini . This is one of the reasons to clarify the status and tribal location of the Dasyscelidius species , thus being the object of differentiation between the short-winged Andean taxa of the tribes Pleminiini and Platyphyllini , which could be confused (Medellin et al. in prep.). The other species included in the genus by Beier (1954, 1962) have the following taxonomic changes:

We propose Dasyscelidius minimus ( Brunner von Wattenwyl, 1895) as nomen dubium. Unfortunately, the only known specimen of the species is lost. It was deposited in the Lübeck Museum ( Germany), but its original description in Latin and its short diagnosis provided later by Beier (1954) in German is not informative, as the sample below translated into English: “small and delicate, yellowish-brown with darker spots, frons darkened, pronotum short, flat, densely and uniformly granulated, dorsally yellowish and laterally chestnut-brown; tegmina strongly reduced, in male not extending beyond first abdominal segment, touching in the midline, densely reticulated; sternum black; legs yellowish with dark mottling; all genicular lobes pointed; male cerci fairly long, styli very short” ( Cigliano et al., 2022). Several Pleminiini and Platyphyllini brachypteran taxa have been described in recent years. However, genera and species of other tribes of Pseudophyllinae are also brachypterous ( Braun, 2002; Cadena-Castañeda, 2011; Cadena-Castañeda & Braun, 2011; Cadena-Castañeda & Monzón, 2014; Cadena-Castañeda et al., 2021), and the characters specified by Beier are not enough to make a suitable identification. In addition, they coincide with several of the known Andean brachypterous species and many others that are still unknown to science.

Dasyscelidius brasiliensis Beier, 1962 , does not fit the diagnostic characteristics of Dasyscelidius reviewed here, so it is necessary to include it in a new genus, described below.

Figures

FIGURE 1. Dasyscelidius atrifrons (Brunner von Wattenwyl, 1895) Female holotype. A. Habitus in lateral view. B. Frons. C. Habitus in dorsal view. D-F. Terminalia: D. Dorsal. E. Lateral and F. Ventral views respectively. “© by Natural History Museum Vienna, NOaS Image Collection / H. Bruckner; published with permission.