Hydrochus pupillus Orchymont

Perkins, Philip D., 2021, Taxonomy of water beetles in the genus Hydrochus Leach, 1817, from Bolivia, Brazil and Paraguay (Coleoptera: Hydrochidae), Zootaxa 4994 (1), pp. 1-93 : 50

Hydrochus pupillus Orchymont

Figs. 5 , 50

Hydrochus pupillus Orchymont, 1939: 254

Hydrochus soekhnandanae Makhan ; incorrect synonymy by Oliva (1996); corrected by Perkins (2019c)

Originally described from Argentina. The following new locality records are from Bolivia and Brazil.

Material examined (8): Bolivia: Beni, 40 km E. San Borja, Estacion Biologica Beni, Palm Camp at Rio Curiraba , (14°44’S, 66°40’W), 6–8.ix.1987, leg. W. E. Steiner (1 NMNH) ; same locality, 13.ix.1987, leg. W. E. Steiner (3 NMNH) . Brazil: Mato Grosso, Corumba , leg. F. Plaumann [no date] (3 NMNH) ; Sao Paulo, Piracicaba , (22°44’S, 47°39’W), 10.i.1966, leg. C. A. Triplehorn (1 NMNH) .

Remarks. The RBINS kindly provided four paratypes of Hydrochus pupillus Orchymont , which are part of the Orchymont collection. Unfortunately, the holotype could not be found. The paratypes consist of two males, and two females. The two males have been dissected, and are conspecific. The females appear to also represent the same species. I have selected one of the males to image the habitus and male genitalia ( Fig. 50 ). Oliva (1996) also noted the four paratypes, but did not mention anything about the holotype.

The male genitalia of H. soekhnandanae and H. pupillus distinctively differ. Refer to the images of H. soekhnandanae in Perkins (2019c) and H. pupillus herein ( Fig. 50 ).

Figures

FIGURE 5. Dorsal habitus of Hydrochus species in study area.

FIGURES 50–51. Habitus and male genitalia. 50. Hydrochus pupillus Orchymont, paratype. 51. Hydrochus drechseli Makhan.