The return of the Duke - locality data for Megadytes ducalis Sharp, 1882, the world's largest diving beetle, with notes on related species (Coleoptera: Dytiscidae) Author Hendrich, Lars Author Manuel, Michael Author Balke, Michael text Zootaxa 2019 2019-04-18 4586 3 517 535 journal article 27000 10.11646/zootaxa.4586.3.8 42d8c42b-cc7c-4c9e-9828-1a73f9eedc4c 1175-5326 2647350 3CFD2CE3-6E93-4DFB-81CB-5406DB34BF2C Megadytes ( Bifurcitus ) magnus Trémouilles & Bachmann, 1980 Megadytes ( Bifurcitus ) magnus Trémouilles & Bachmann, 1980 : 118 (orig. descr.); Trémouilles 1989b: 161; Miller & Bergsten 2016 : 108 ; Nilsson & Hájek 2019 : 81 . FIGURE 6. Megadytes magnus : A) median lobe with parameres in ventral view, B) tip of median lobe in lateral view, C) median lobe in ventro-apical view to show the long nose-like tip. Scale bars = 1.5 mm. FIGURE 7. Megadytes ducalis , male from collection Guignot: A) frontal view, B) ventral view of head and protarsus, C) left middle leg, D) dorso-lateral view of left side of head, pronotum and elytral base, E) ventro-lateral view of left hind leg. Scale bars = 5 mm. FIGURE 8. Megadytes lherminieri , male, Ecuador, Esmeraldas: A) ventral view of head, left protarsus and left middle leg, B) dorsal view of left protarsus, C) ventro-lateral view of left hind leg; M. magnus , male, Paraguay, cerro Lambaré: D) ventral view of head, right protarsus and right middle leg, E) dorsal view of left protarsus, F) ventro-lateral view of left hind leg. Scale bars = 5 mm. Type locality . Argentina , Santa Fe . Type material examined . Paratype : 1 male , " Argentina : S. Fe Ceres III.1943 leg. Polmer " [handwritten label], " PARATYPUS " [red printed label], "Brit. Mus. 1989-185" [printed label], " Col. A.O. Bachmann " [printed label], " Megadytes (Bifurcitus) magnus E.R. Tremouilles y A.O. Bachmann ano 1979" [red handwritten label] ( BMNH ) . Other material examined. Paraguay : 1 male , 2 females , " Paraguay / Chaco Dep. Boquéron 10 km SE Mariscal Estigarribia , 2.2.1990 , leg. U. Drechsel " (CLH); 4 males , 6 females , " Paraguay / Chaco Dep. Boquéron 10 km SE Mariscal Estigarribia , 10.2.1990 , leg. U. Drechsel " ( CLH , ZSM ) ; 1 male , " Paraguay / Cerro Lambaré , 5.6.1992 , leg. U. Drechsel / Coll. Hendrich " ( CLH ) ; 1 male , " Paraguay / Dep. Central , Asunción , 31.10.1991 , 5.6.1992 , leg. U. Drechsel / Coll. Hendrich " ( CLH ) ; Brazil : 1 female , " Brasilien , Sao Paulo , 10.12.1984 , in swimming pool, Gottwald leg." ( CLH ) . Descriptive notes . A description of this species was given by Trémouilles & Bachmann (1980) . Here we provide photos of the habitus ( Figs 1C, F , 2C ) and focus on morphological characters of the male in different views ( Figs 8 D–F). The median lobe with both parameres of a specimen from Mariscal Estigarribia in Paraguay , is figured in ventral view ( Fig. 6A ), the tip of the median lobe in lateral view ( Fig. 6B ), and the tip of median lobe in ventro-apical view ( Fig. 6C ). Note that Figs 6A and C show the median lobe of the same individual, tilted at different angles. Distribution . Southern part of tropical and subtropical South America. The species was described from Argentina , Paraguay and Uruguay , and later recorded from Brazil (Trémouilles 1989b) ( Fig. 11 ). Habitat . Unknown, probably similar to M. lherminieri . Most of the specimens in Paraguay were collected at light in a savannah region with temporary swamps and permanent farm dams. The swimming pool in Sao Paulo, were the single female has been collected, was not far away from a big reservoir or dam, overgrown with water lilies and water hyacinths (S. Gottwald pers. com.).