Hydrochus secretus Knisch, 1996

Perkins, Philip D., 2019, Type designations for Neotropical water beetles in the genus Hydrochus Leach 1817 (Coleoptera: Hydrochidae), Zootaxa 4701 (2), pp. 149-167 : 160

Hydrochus secretus Knisch

Figs. 9 , 13E

Hydrochous secretus Knisch 1921: 2 .

Hydrochus mahunkai Makhan 1993 ; Oliva (1996).

The RBINS kindly provided five syntypes of Hydrochus secretus Knisch , which are part of the Orchymont/Knisch types collection . The syntypes consist of two males, and three 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, a good specimen, to serve as lectotype, have labeled it such, and have imaged the habitus, male genitalia and labels of this specimen ( Figs . 9 , 13E ). The second male was dissected by a prior worker; the specimen is quite fragmentary, in five pieces. Lectotype labels ( Fig. 13E ): “ Coll. R. I. Sc. N. B. Bras.Corumba [ Matto Grosso ] // Kniž det. secretus m. // Coll. A. Knisch COTYPUS // Ex Coll. A. d’Orchymont // Hydrochus secretus Knisch det. J.L.Hellman // HABI- TUS/GENIT. DIGITAL IMAGES captured 2019 P. D. Perkins // [red] LECTOTYPE Hydrochus secretus Knisch desig. P. D. Perkins. ” The four non-lectotype syntypes have been labeled paralectotypes.

Remarks. Oliva (1996) placed Hydrochus mahunkai Makhan 1993 as a junior synonym of Hydrochus secretus Knisch. I have examined the holotype and male genitalia of Hydrochus mahunkai Makhan , provided through the courtesy of the HMNH, and concur with the synonymy. Labels on holotype of H. mahunkai : “Soil Zoological Exp. BOLIVIA, Guayaramerin / Beni / outskirts of town BALOGH, MAHUNKA, ZICSI // No. 424 lamping 1.XII.1966 // Hydrochus mahunkai det. D. Makhan 1993 // Holotype [red] // Hydrochus secretus Knisch, 1921 Det. A. Oliva 1996 ”. The drawing of the male genitalia in Makhan (1993) is grossly inaccurate, especially in the shape of the basal piece.

Figures

FIGURE 9. Hydrochus secretus Knisch, habitus and male genitalia of lectotype.

FIGURES 13A–E. Labels of lectotypes and neotype. (A) Hydrochus metallipes Knisch; (B) Hydrochus pumilio Knisch; (C) Hydrochus purpureus Knisch; (D) Hydrochus tarsalis Chevrolat; (E) Hydrochus secretus Knisch.