Dongodytes Deuve

Tian, Mingyi, Yin, Haomin & Huang, Sunbin, 2014, Du'an Karst of Guangxi: a kingdom of the cavernicolous genus Dongodytes Deuve (Coleoptera, Carabidae, Trechinae), ZooKeys 454, pp. 69-107 : 71-74

Taxon classification Animalia Coleoptera Carabidae

Genus Dongodytes Deuve

Dongodytes Deuve, 1993: 292

Type species.

Dongodytes fowleri Deuve, 1993: 292

Type locality.

Jiabao Dong, in Bama County, northwestern Guangxi ( Uéno 1998).

Diagnostic characters of the genus.

Members of Dongodytes share the following combined characters: elytra remarkably elongate though much wider than prothorax and without shoulders; eyes completely effaced and depigmented; body especially head and prothorax strongly elongate; frontal furrows very short, mandibles long and slender, right mandible bidentate, palps and antennae very elongate and thin; propleura strongly tumid, visible from above; pronotum much longer than wide; elytra depressed medially on humeral parts, anterior and preapical dorsal pores present or not, humeral set of marginal umbilicate pores not aggregated, 1st pore widely located from 2nd and 3rd which are close to each other, 1st to 3rd more or less adjoining marginal gutter, 4th distinctly dorsal wards located and far from marginal gutter; 5th and 6th of middle set are close to each other; legs thin and very long, tarsi slender; protarsi not distinctly modified in male.

Male genitalia are strongly diversified in Dongodytes and could be important character states for phylogenetic analysis of the genus. Three types of the median lobe can be recognized. Type I, species of the subgenus Dongodytes (s. str.) which are known only from Du’an Karst, the median lobe is very short and stout, basal orifice very large, but with a very small, sometimes indistinct, sagittal aileron, and the parameres are broader (Figs 33-38); Type II, species of the subgenus Dongodytodes , which are all known from Du’an Karst, the median lobe is very elongate and thin, basal orifice comparatively small, but with a large sagittal aileron, and slender parameres (Figs 39-46); Type III, species of Dongodytes (s. str.) which are all known from other counties rather than Du’an: the median lobe is intermediately shaped between the two patterns described above, moderately elongate, rather stout, and with a large sagittal aileron; in particular, the median lobe distinctly curved at apex ( Deuve 1993: Fig. 2; Uéno 1998: Figs 1-4).

Systematic position of Dongodytes .

Dongodytes is one of the most modified troglobiomorphic genera of trechines in the world. To determine the taxonomic position of Dongodytes within the tribe Trechini remains a challenge. Vigna Taglianti (1997) and Uéno (1998) suggested it may be allied to the European Aphaenops series, contrary to Deuve (1993) who compared Dongodytes with Sinaphaenops Uéno & Wang, 1991. Because recent study based on molecular phylogenetic analysis have clearly demonstrated that the Aphaenops series in the widest and traditional sense are restricted to the Pyrenean lineage ( Faille et al. 2010, 2013), we agree with Deuve’s opinion. Dongodytes seems to be allied to its Chinese congeners such as Sinaphaenops and Pilosaphaenops Deuve & Tian, 2008. For example, by having very short frontal furrows, very elongate genae and slender neck constriction, the head structures of Dongodytes are more or less similar to those of Sinaphaenops and Pilosaphaenops . Furthermore, all of the above genera have similar prothorax although latero-marginal setae are always absent in Sinaphaenops and Pilosaphaenops .

Geographical distribution.

Endemic to northwestern Guangxi (Fig. 73). Members of Dongodytes are recorded from several counties of Hechi Prefecture. However, only a single species is known in each of Bama, Fengshan, Tian’e and Dahua Counties, respectively. On the other hand, majority of the species (eight) are distributed in Du’an County. Thus, it is clear that, from the present knowledge, all species of Dongodytes are distributed in a very limited area of the river Hongshui He drainages in northwestern Guangxi. The river acts as a natural barrier for dispersal of Dongodytes at only a specific level. The nominate subgenus Dongodytes (s. str.) covers a larger distribution range than the subgenus Dongodytodes which is restricted to Du’an Karst in the eastern or northern bank of Hongshui He.

Taxonomic treatment.

Species of Dongodytes are divided into two subgenera, Dongodytes (s. str.) Deuve and Dongodytodes Tian. Both subgenera can be separated each other by shape of head, length of antennae, body pubescent or not, and chaetotaxal pattern on head, pronotum, elytra, and abdominal ventrite VII of male ( Tian 2011). See the following key for details.

Key to subgenera and species of Dongodytes Deuve