Species groups in the genus Cubitermes (Isoptera: Termitidae) defined on the basis of enteric valve morphology

Abstract

Seventy-four species, forms and varieties of Cubitermes Wasmann, 1906 have been studied, including taxa placed in synonymy with other species. Within this group of taxa, the enteric valve, mainly of the workers and soldiers, provided the best and the only clear-cut criteria for distinguishing some major subsets that are proposed here as species groups.The genus Cubitermes is re-described; the morphologies of the enteric valves are described in detail including the number of spatulae at the downstream end of the primary cushions; the possible presence of crests or bulges near the downstream end of the primary cushions; the overall shape of the primary cushions; the number of lateral supporting bristles; the kind of symmetry of the valve; and the structure of the secondary cushions. These characteristics are used to define nine species groups. For now, these groups have no taxonomic ranking but are helpful as regards species recognition. Identification keys for species groups are provided for soldiers and workers together with a partial key for imagines. Geographical ranges of the groups are also provided. On the basis of enteric valve morphology, some synonymies can no longer be validated: (a) C. planifrons Sjöstedt, 1924 is not a synonym of C. fungifaber (Sjöstedt, 1896); (b) C. kemneri Emerson, 1928 is not a synonym of C. zenkeri (Desneux, 1904); and (c) C. fungifaber var. elongata Sjöstedt, 1924 does not belong to the species C. fungifaber. Cubitermes planifrons and C. kemneri become valid again and C. fungifaber var. elongata is an invalid name.

Phylogeny and revision of the ‘Cubitermes complex’ termites (Termitidae: Cubitermitinae)

“…Krishna et al . (2013b) listed 67 valid species‐group names, while Josens & Deligne (2019) proposed some new species and some invalid synonyms among the species that were synonymized by Ruelle (1975) and by Krishna et al . (2013b), bringing the number of species to 81.…”

“…As in the soldierless Apicotermitinae (Sands, 1972), the Cubitermes enteric valve armature (EVA), mainly of the worker caste, can be used for differentiating species groups (Josens & Deligne, 2019). In the subfamily Cubitermitinae, the basic enteric valve is a funnel bearing six elongated primary, prominent cushions of the valve (PC) alternating with non‐prominent, secondary cushions of the valve (SCs) (Noirot, 2001).…”

“…Bouillon & Vincke (1971) mentioned the existence of at least three main kinds of EVA in the genus Cubitermes , with or without sclerotized spatulae. Josens & Deligne (2019) distinguished nine species groups on the basis of their EVA. Six of them are variations on the basic EVA, but three of them, namely the sankurensis , oblectatus and sulcifrons groups are characterized by the presence of two, three and six sclerotized spatulae on the PC, which project from the valve into the paunch (P3).…”

“…5). One of the main conclusions from Josens & Deligne (2019) is that several species may have soldiers with similar external morphologies, which used to make Cubitermes so difficult to identify, but may possess different types of EVA. A brief overview of EVA is given in Table 1 (modified from Josens & Deligne, 2019: Table 4).…”

“…The taxonomy of Cubitermes complex genera has been obscured by many inadequately detailed historical descriptions. A first step in modernizing the taxonomic concepts of this genus was to split it into nine species groups according to their EVA (Josens & Deligne, 2019). Whether or not these groups should be raised to generic rank remains subjective although genetic data helps discriminate groups of related taxa.…”