Hydrochus spanglerorum, Perkins, 2019

Perkins, Philip D., 2019, Hydrochus spanglerorum n. sp., a remarkable, highly derived species from Brazil Guyana, and Suriname (Coleoptera: Hydrochidae), Zootaxa 4701 (6), pp. 581-587 : 581-586

Hydrochus spanglerorum n. sp.

Figs. 1 , 3 (habitus), 2 (male genitalia); 4, 5 (male genital segments), 8, 9 (female genital segments)

Type Material. Holotype (male): “ Brazil: Para ; Rio Xingu Camp (52º 22’ W, 3º 39’ S) Altamira (ca. 60 km S.), 12 Oct 1986, P. Spangler & O. Flint // Colln . #21, pond at 2nd palm grove on trail 1” (NMNH) . Paratypes (37): Brazil: same data as holotype (3 NMNH); Same data, except 11 Oct 1986, colln. #20, P. Spangler & R. Crombie (7 NMNH) ; Same data except 15 Oct 1986, P. Spangler & O. Flint (11 NMNH). Guyana: Mazaruni-Potaro District, Skull Point , 23 December 1982, W. E. Steiner ” [6°24’00.0”N 58°41’00.0”W] (9 NMNH) . Suriname: Sipaliwini District, N 4º 10.521’ W56º 47.244’, 228m, Camp 1, on Kutari River ; leg. Short and Kadosoe; forest stream, 20.viii.2010; SR10- 0820-01A, 2010 CI-RAP Survey (2 SEMC) . Sipaliwini District, N 2.97731º, W55.38500º, 200m, Camp 4 (low), Kasikasima, sandy stream on trail to METS camp, 20.iii.2012; SR12-0320-02A, leg. A. Short; 2012 CI-RAP Survey (4 SEMC, NZCS) . Sipaliwini District, N 4º 40.432’ W56º 11.079’, 86m, Raleighvallen Nature Reserve base of Voltzberg; pooled up stream; leg. Short et al., 16.iii.2016; SR16-0316-01B (1 SEMC).

Differential Diagnosis. Recognized by the combination of large size, dull gold dorsal color, the densely punctate head and pronotum, the tumid and grooved frons, the uniquely colored and densely punctate femora, the unusual elytral sculpture, and the unique, highly derived male genitalia, which have the orifice of the basal piece articulated with the basal piece proper, the parameres, which in most species of the genus articulate with the distal end of the basal piece, have become completely fused with the basal piece, and the aedeagus dorsal basal lobe (adbl) has become enlarged and is located distally

Description. Size: holotype (length/width, mm): body (length to elytral apices) 4.50/1.63; head width 1.03; pronotum l/ w 1.03 /1.10; pronotum anterior margin 1.00; pronotum basal margin 0.83; elytra 2.77/1.63. Large (ca. 4.46–5.31 mm), elongate, last third of elytra narrowed. Habitus as illustrated ( Figs. 1 , 3 ). Dorsum dull gold, with very faint iridescence, with grayish mottling on elytra. Legs dark brown except ventral surface of femora often bright silver metallic with violet tint; all surfaces of femora densely coarsely punctate; tibiae with outer apical margin produced and bearing few short stout spines. Pronotum very densely, moderately coarsely punctate. Elytral striae with deep round punctures; interstriae wider than striae.

Head densely, moderately coarsely punctate; frons markedly raised in middle, with deep groove on each side of timidity; frontoclypeal suture absent.

Pronotum wider than long (L/W as ca. 1.03/1.10), widest at about distal 2/3; anterior margin arcuate; narrowed at base; sides smooth, sinuate; punctures on pronotum moderately sized, deep, very dense; disk raised; depressions moderately deep in anterior, very shallow in posterior.

Elytra with strial punctures ca. 2x those on pronotum; interstriae ca. 1.5– 2x width of striae, with indistinct minute granules smaller than ommatidia; 5 th interstria raised, convex throughout length, except very short distance apically, not additionally raised at usual area of callus; 9 th interstria raised and overhanging 10 th; apices rounded, with submarginal row of large, elongate punctures ( Fig. 3 ).

Etymology. Named in honor of Paul and Phyllis Spangler, who devoted most of their lives to water beetle taxonomy. Together they collected hundreds of thousands of specimens of all water beetle groups, many from the Neotropics. These specimens have enriched the scientific contributions of many taxonomists, and will continue to do so far into the future.

Remarks. A few duplicate specimens are deposited in the MCZ and SEMC.

Figures

FIGURE 1. Hydrochus spanglerorum n. sp., dorsal, lateral and ventral habitus of holotype.

FIGURES 3–5. Hydrochus spanglerorum n. sp. (3) posterior view of holotype. (4) genital segments of holotype, dorsal view. (5) genital segments of holotype, ventral view.