Papuadessus
Contents
Ordo: Coleoptera
Familia: Dytiscidae
Subfamilia: Hydroporinae
Tribus: Bidessini
Genus: Papuadessus
Name
- Papuadessus Balke, 2001 Wikispecies link
- Gender: masculine
- Original status: valid genus
Type species
- Papuadessus pakdjoko Balke, 2001
Species (2)
Papuadessus pakdjoko, Papuadessus baueri
Taxonomy
Large, length 3.1 - 3.4 mm. Body elongate-oval; base of pronotum distinctly more narrow than base of elytron, continuously narrowing towards head. Neither a cervical (see Biström 1988a, = occipital line, e.g. of Larson et al. 2000) nor a sutural line present. Pronotal and elytral plica present; pronotal plica long, sinuate; elytral plica very short, indistinct in some specimens. Epipleura lack a basal pit which is posteriorly delimited by a carina. In Biström's (1988a) key to world genera of Bidessini, Papuadessus runs to couplet 14, which contains Microdessus and Uvarus. Microdessus is a monotypic South American genus, which is characterised by possession of four distal processes on the median lobe of aedeagus. Uvarus is a problematic group. Its type species is the American Hydroporus lacustris Say, the types of which are lost, however (Larson et al. 2000). The genus as currently viewn contains > 50 species, and has a wide range, spanning North and Central America, Africa, Asia and Australia. It was pointed out that it may be paraphyletic and is in need of global review (Biström 1988a, b; Larson et al. 2000). Papuadessus differs from Uvarus in that it is larger (Uvarus: < 2.8 mm), and has a simply runded tip of paramere (with emargination or small hook or otherwise modified in Uvarus). In P. pakdjoko, there are two marginal tongue-like lamellae on the ventral surface of the elytron: one in the middle, and one apically (Figure 7). Only one such lamella is present for example in Liodessus species I (Balke) have examined, the apical one (Figure 8). However, both character states are widely distributed among Bidessini genera and the informative value for phylogenetic analysis remains to be evaluated.
References
- Balke, M. 2001: Papuadessus pakdjoko – a new genus and species of rheobiont diving beetle from New Guinea of potential use for environmental impact assessments (Coleoptera, Dytiscidae). Hydrobiologia, 464: 107-112.
