Crucisternum queneyi, Girón & Short, 2018

Giron, Jennifer C. & Short, Andrew Edward Z., 2018, Three new genera of acidocerine water scavenger beetles from tropical South America (Coleoptera, Hydrophilidae, Acidocerinae), ZooKeys 768, pp. 113-158 : 118-120

Crucisternum queneyi sp. n. Figs 1E-H ; 6J ; 7

Type material examined.

Holotype (male): FRENCH GUIANA: Sinnamary: "[Pripris de Yiyi]/ 25.xi.2007/ P. Queney réc.” (MNHN). Paratypes (2): FRENCH GUIANA: Roura: "[Patawa: ru]/ 19.xi.2007/ P. Queney réc.” (1, SEMC); "[N2, PK 73,5: petite crique accidentée, 250m]/ 23.xi.2007/ P. Queney réc.” (1, PQPC).

Differential diagnosis.

Crucisternum queneyi is very similar to C. ouboteri and C. vanessae in the sharpness of the punctation and the general coloration of the body (compare Fig. 1E-H to Fig. 2 ). It can be readily recognized by the pear-shaped aedeagus (as opposed to fusiform), with simple (as opposed to broadened) margins of the apical region of the median lobe, as well as outwardly pointing apices of the parameres (see Fig. 6J ).

Description.

Body length 1.9-2.3 mm, width 1.0-1.1 mm. General coloration dark brown on elytra, slightly paler on pronotum and head (Fig. 1E ). Elytra with punctures rather sharply marked. Aedeagus pear-shaped, widest along basal third; apex of parameres pointing outwards; apical third of median lobe narrower than a paramere at the base of its apical third, with simple converging margins; gonopore located near midlength of median lobe (Fig. 6J ).

Etymology.

Named after French coleopterist Pierre Queney, who collected and beautifully prepared the known specimens of this species.

Distribution.

French Guiana (Roura). See Fig. 7 . Collected at 250 m elevation.

Biology.

This species is known from streams.

Figures

Figure 1. Habitus of Crucisternum spp.: A-D Crucisternum escalera: A dorsal view B lateral view C ventral view D head E-H Crucisternum queneyi: E dorsal view F lateral view G ventral view H head. Scale bars: 1 mm.

Figure 2. Habitus of Crucisternum spp.: A-D Crucisternum ouboteri: A dorsal view, B lateral view C ventral view, D head E-H Crucisternum vanessae: E dorsal view F lateral view G ventral view H head. Scale bars: 1 mm.

Figure 6. Aedeagus of Crucisternum spp.: A-B Crucisternum ouboteri: A Guyana B Brownsberg C Crucisternum toboganensis D Crucisternum vanessae E-F Crucisternum xingu: E colln 6 F colln 23 G-H Cuscisternum sinuatus: G colln 23 H BR 18 - 0302 - 04 A I Crucisternum escalera J Crucisternum queneyi. Scale bars: 0.25 mm.

Figure 7. Distribution of Crucisternum species.