Betiscoides Sjoestedt , 1924

Matenaar, Daniela, 2024, Application of extended depth of field 3 D imagery to tackle the challenges of cryptic species: a use case in the genus Betiscoides Sjoestedt, 1924 (Orthoptera, Caelifera, Lentulidae) and its taxonomic implications, Evolutionary Systematics 8 (1), pp. 65-90 : 65

Genus Betiscoides Sjoestedt, 1924

Remarks.

The genus Betiscoides Sjöstedt, 1924 was described by Sjöstedt (1924) and revised by Key (1937). Further descriptions of the morphological characters of Betiscoides with altered terminology followed (e.g. Dirsh 1965) and considering the new findings of this study, it is reasonable to provide a revised definition of the genus.

Definition.

Type species: Betiscoides meridionalis Sjöstedt, 1924, type locality: South Africa. Body slender or thin, elongate, stick-like, smooth or hairy, with a prominent ventral line of hairs along the abdomen or at the end of tergits five to eight. Antennae thin or thick ensiform, segments strongly separated, finely and evenly rugose. Head in dorsal view conical. Frontal ridge compressed between antennae. Eye longitudinal or ovate and prominent. Pronotum cylindrical, with very weak or no median carina. Prosternal process trapezoid, T-shape, or lamelliformly compressed, laterally either flat or raised in the anterior or posterior part. Mesosternal interspace reduced, mesosternal lobes connected. Abdomen with fine longitudinal, dorsal median carina. Tympanum absent. Anterior and middle legs short; sometimes hairy, hind femur slender. External apical spine present. Tarsus shorter or half the length of the tibia. Arolium large, sometimes white. Male supra-anal plate triangular in dorsal view. Cerci very small, straight and conical. Subgenital plate elongate and conical. Female ovipositor valves slightly or strongly recurved at the tips; not toothed.

A phylogenetic reconstruction revealed that the sister taxon of the genus Betiscoides is Gymnidium Karsch, 1896 ( Matenaar et al. 2016). The genus Betiscoides contains the following species: Betiscoides meridionalis Sjöstedt, 1924, B. parva Key, 1937, B. sjostedti Key, 1937, B. nova sp. nov. and B. muris sp. nov. While the description of B. meridionalis and B. sjostedti remains valid concerning the hairiness of the body, the body and especially the end of the abdomen of B. parva is fairly hairy (Fig. 6 ) and thus, its character description is hereby revised. In order to extend the definition for the three known nominal species considered by Key (1937), I provide the following additional morphological characters analyzed in the specimens collected at, or very close to, the type localities of the nominal species: ratio of the eye length to the length of the fastigium, degree of the male subgenital plate, volume of the body and, volume of the visible part of the eye. In addition, I provide measurements of the "female genital characters" for B. meridionalis .

Figures

Figure 6. Overview of the nominal species of Betiscoides. A. B. sjostedti, HLMD-Cael- 382, B 21, DEL 8; B. B. parva, HLMD-Cael- 381, B 103, DEL 9, and C. B. meridionalis HLMD-Cael- 380, LB 11, DEL 3. Specimens were collected at or close to the respective type localities. Scale bars: 1 mm.