Hydrochus variabilis Knisch

Perkins, Philip D., 2019, Type designations for Neotropical water beetles in the genus Hydrochus Leach 1817 (Coleoptera: Hydrochidae), Zootaxa 4701 (2), pp. 149-167 : 162-164

Hydrochus variabilis Knisch

Figs. 11 , 12C

Hydrochous variabilis Knisch 1921: 2 . The RBINS kindly provided fifteen syntypes of Hydrochus variabilis Knisch , which are part of the Orchymont/ Knisch types collection. The syntypes consist of both males and females. I have selected one of the males, a specimen in good condition, to serve as lectotype, have labeled it such, and have imaged the habitus, male genitalia and labels of this specimen ( Figs. 11 , 12C ). Lectotype labels ( Fig. 12C ): “ Coll. R. I. Sc. N. B. Bras.Corumba [Matto Grosso] // Kniž det. variabilis // Coll. A.Knisch COTYPUS // Ex Coll. et det. A.d’Orchymont: R.M.H.N.B. 15.962 // Hydrochus variabilis Knisch det. J.L.Hellman // Paralectotype // HABITUS/GENIT. DIGITAL IMAGES captured 2019 P.D. Perkins // [red] LECTOTYPE Hydrochus variabilis Knisch desig. P. D. Perkins. ” The fourteen non-lectotype syntypes have been labeled paralectotypes.

Remarks. The male genitalia of the lectotype appears to have a very large gonopore; this is, based on other specimens of this species examined, because the male genitalia had dried out, and the membranous area surrounding the gonopore had consequently retracted toward the lateral margins. Images of a specimen of H. variabilis with the gonopore of usual size is given in Perkins (in press).

Figures

FIGURE 11. Hydrochus variabilis Knisch, habitus and male genitalia of lectotype.

FIGURES 12A–E. Labels of lectotypes. (A) Hydrochus ducalis Knisch; (B) Hydrochus drakei Knisch; (C) Hydrochus variabilis Knisch; (D) Hydrochus corruscans Bruch; (E) Hydrochus argutus Knisch.