Hydrocanthus debilis Sharp, 1882

Hydrocanthus debilis Sharp, 1882 . Type locality: Brazil, Bahia / Amazonas, Amazonas Valley. Sharp 1882a: 281 (orig. descr.);

Sharp 1882b: 8; Branden 1885: 18; Régimbart 1889: 263; Régimbart 1895: 343; Meinert 1901: 413; Régimbart 1904: 225;

Zimmermann 1919: 118; Zimmermann 1920a: 14; Zimmermann 1920b: 225; Zimmermann 1921: 206; Zimmermann

1924: 1; Zimmermann 1925: 1; Zimmermann 1928: 167; Blackwelder 1944: 73; Ferreira-Jr. et al. 1998: 133; Benetti &

Hamada 2003: 704; Ferreira-Jr. & Braga 2009: 325; Nilsson 2011: 22; Macchia et al. 2015: 113. Hydrocanthus (s. str.) debilis Sharp, 1882: Guignot 1957: 5; Young 1979: 2; Nilsson 2005: 111. Hydrocanthus (Guignocanthus) debilis Sharp, 1882: Young 1985: 98. Hydrocanthus finitimus Guignot, 1942 . Type locality: French Guiana, Cayenne. Guignot 1942: 45 (orig. descr.); Spangler 1966:

387; Young 1985: 98 (N. Syn.). Hydrocanthus (s. str.) finitimus Guignot, 1942: Guignot 1956: 396; Guignot 1957: 5. Hydrocanthus rubiginosus Guignot, 1942 Syn. nov. Type locality: French Guiana, Cayenne. Guignot 1942: 47 (orig. descr.);

Nilsson 2011: 26. Hydrocanthus (s. str.) rubiginosus Guignot, 1942: Guignot 1957: 5; Nilsson 2005: 111.

Type material examined. Hydrocanthus debilis . Syntypes. “ BRAZIL, Bahia, 497, Sharp Coll. 1905–313” (1 ♂ 1 ♀ / BMNH). Hydrocanthus finitimus . Holotype ♂. “ GUIANA, Cayenne, III.1937, coll. Guignot ” (MNHN). Paratypes. “ GUIANA, Cayenne, III.1937, coll. Guignot ” (1 ♂ 2 ♀♀ / MNHN). Hydrocanthus rubiginosus . Holotype ♀ (Fig. 7). “ GUIANA, Cayenne, III.1937, coll. Guignot ” (MNHN) . Paratypes. “ GUIANA, Cayenne, III.1937, coll. Guignot ” (2 ♀♀ / MNHN) .

Taxonomic notes. The comparison of type material of both taxa confirms that Hydrocanthus rubiginosus Guignot, 1942 is a junior subjective synonym of Hydrocanthus debilis Sharp, 1882 . The particular combination of light reddish-brown pronotum and dark reddish-brown elytra with yellowish marmorations (Fig. 7b), prosternum laterally and medially setose, prosternal process entirely setose except along the apical margin, metaventrite laterally and apically setose (Figs 2d, 7c), and small size (4.00– 4.10 mm) is unique within the known females of this genus.

Additional notes. In Nilsson’s catalogues (NILSSON 2005, 2011) the type locality for Hydrocanthus rubiginosus is reported as “ French Guiana> Abonnenc”, however in the original description (Guignot 1942), the author mentions “ Guyane française: Cayenne (Abonnenc)”; Abonnenc is reported as the collector (probably referring to Émile Abonnenc) not as the locality.