Helochares (Hydrobaticus) laevis,

Short, Andrew Edward Z. & Girón, Jennifer C., 2018, Review of the Helochares (Hydrobaticus) MacLeay of the New World (Coleoptera: Hydrophilidae: Acidocerinae), Zootaxa 4407 (1), pp. 29-50: 36

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Helochares (Hydrobaticus) laevis

n. sp.

Helochares (Hydrobaticus) laevis  n. sp.

Figs. 4BView FIGURE 4, 7JView FIGURE 7, 10BView FIGURE 10.

Type material. Holotype (male): “ MEXICO: Chiapas / San Cristobal las Casas / 17-21.vii.1964 / leg. P.J. Spangler ”, “grass chocked stream on edge of town” ( USNM). 

Paratypes: (5): MEXICO: Chiapas: 20 km NE of San Cristobal de las Casas on road to Tenejapa, Las Ollas , “bog”, 6.iii.1965, leg. D. E. Breedlove (4 females, CAS, SEMC); same data as holotype (1 female, USNM)  .

Differential diagnosis. Body size 6.2–6.8 mm. Clypeus dark yellow to orange with the central third darkened to dark brown. Elytra without any detectable serial punctures or striae ( Fig. 4BView FIGURE 4). Abdominal ventrites uniformly dark brown; pubescence dense and evenly distributed, the longest hairs shorter than those on the metaventrite. Aedeagus ( Fig. 7JView FIGURE 7) 2.3-times longer than its greatest width; apex of parameres truncate, with outer corners rounded; inner corners of apex of parameres forming an acute angle; lateral outer margins of parameres parallel along basal two thirds, slightly constricted at two thirds, diverging along apical third; maximum width of aedeagus at basal half, clearly narrower than maximum width of aedeagus at apical half; median lobe with apex gradually tapering to an acute point.

This species is extremely similar to H. politus  , with the primary difference being in the form of the aedeagus ( Fig. 7JView FIGURE 7).

Description. In addition to differential diagnosis: pronotum dark brown to black in central half ( Fig. 4BView FIGURE 4). Ground punctation on head and pronotum moderately impressed, slightly less impressed on the elytra.

Distribution. Mexico (Chiapas) ( Fig. 10BView FIGURE 10).

Etymology. Laevis (L), after the smooth elytra which lacks any coarse serial punctures or striae.

Biology. One series was collected in a “bog”, while the other was collected in a “grass chocked stream”.


Smithsonian Institution, National Museum of Natural History


California Academy of Sciences


University of Kansas - Biodiversity Institute