Enochrus algarum, Jia & Short, 2013

Jia, Fenglong & Short, Andrew E. Z., 2013, Enochrus algarum sp. nov., a new hygropetric water scavenger beetle from China (Coleoptera: Hydrophilidae: Enochrinae), Acta Entomologica Musei Nationalis Pragae 53 (2), pp. 609-614 : 610-612

Enochrus algarum sp. nov.

( Figs 1–9 )

Type material. HOLOTYPE: J ( SYSU): China, Fujian, Ningde, Zhitishan Mount , ca. 26°48′48.36″N, 119°22′59.76″E, 750 m, in decaying plant materials beside wet rock, 3.x.2012, Zeyu Wang leg [translation; labeled in Chinese] . PARATYPES: 2 ♀♀ ( SYSU, SEMC): China: Fujian Province, Wuyishan Mount, Da’an, the wet rock near the roadside of upper Chongyang river, 447.5 m, 27°57′32″N 117°51′58″E, 15.vii.2010, Fenglong Jia leg. [translation; labeled in Chinese] .

Diagnosis. Maxillary palps very short, half as long as the width of the head. Elytra with ten rows of weakly impressed striae. Fifth abdominal ventrite entire, without any emargination, truncation, or thickened setae. Aedeagus with parameres curved outwards apically.

The new species is most similar to E. (Holcophilydrus) laoticus Hebauer, 2005 , and will loosely key to this species in JIA & WANG (2010). The short maxillary palps, weakly impressed elytral striae and the morphology of the aedeagus distinguish it easily from the latter species.

Description. Form and color. Body length 4.9 mm, body width 2.8 mm. Body oval, moderately convex. Dorsum of pronotum and elytra dark brown, with lateral margins of elytra markedly paler. Head dark brown to black, with margins of clypeus brown to light brown. Maxillary and labial palps reddish yellow, not darkened apically. Venter, including legs, brown to dark brown.

Head. Antennae with scape subequal in length to antenommeres 2–6 combined. Maxillary palps short, ca. half the width of head anterior to eyes; apical and penultimate segments subequal in length ( Fig. 6 ). Clypeo-labral margin evenly arcuate, without median emargination. Labrum with a median row of setiferous systematic punctures, which are subequal in size the surrounding ground punctation. Frons and clypeus with ground punctation moderately coarse, distance between punctures 2–3× the width of one puncture; setiferous systematic punctures present mesally of each eye. Mentum subquadrate, with anterior margin moderately depressed medially ( Fig. 5 ); set with sparsely arranged coarse punctures.

Thorax. Ground punctation on pronotum and elytra moderately coarse, distance between punctures 1–2× the width of one puncture. Elytra with ten faint rows of serial punctures slightly larger than surrounding ground punctation and most prominent in posterior third ( Figs 1–2 ); punctures lack any setae. Prosternum not tectiform or carinate, with a transverse groove, set with very sparse setae on anterior margin. Mesoventrite with a glabrous, stout, backwardly pointing projection ( Fig. 4 ), rising to a level of mesocoxae. Metaventrite with a very indistinct elongate oval glabrous area posteromedially, slightly longer than wide; glabrous area slightly more than half the total length of the metasternum. Mesofemora densely pubescent on basal two-thirds. Metafemora very sparsely pubescent ( Fig. 3 ), with setae slightly more dense basally. Each elytron with sutural stria on posterior three-fourths ( Fig. 1 ). Anterior claws in male distinctly stronger and more angularly curved than in female, bearing smaller basal tooth; posterior claws only slightly more curved than in female, without basal tooth.

Abdomen. Ventrites uniformly and densely pubescent. Fifth (apical) ventrite entire, without trace of emargination or trunctation, and without margin of coarse setae. Aedeagus with phallobase about 1.4× as long as parameres. Parameres broad, longer than median lobe, abruptly truncate and strongly bent outwards apically. Median lobe narrower than parameres, gradually narrowed from base to apex, sharp apically ( Fig. 7 ).

Etymology. The specific name refers to the habitat of this species with abundant algae.

Habitat. Both collecting events for this species were from hygropetric habitats ( Fig. 8–9 ). The paratypes were specifically on wet rock with dense algae while the holotype was found in detritus beside wet rocks. Specimens were collected together with other known hygropetric taxa, including, Oocyclus fikaceki Short & Jia, 2011 , Coelostoma stultum (Walker, 1858) , and Satonius jaechi Hájek, Yoshitomi, Fikáček, Hayashi & Jia, 2011 (Torridincolidae) .

Distribution. China (Fujian).

Figures

Figs 1–7. Morphology of Enochrus algarum sp. nov. 1–3 – habitus (1 – dorsal view, 2 – lateral view, 3 – ventral view); 4 – mesoventral process; 5–6 – head (5 – ventral view, 6 – dorsal view); 7 – aedeagus. 1–2, 6–7 – male, holotype; 3–5 – female, paratype.

Figs 8–9. Habitat of Enochrus algarum sp. nov. at Wuyi Shan Mts. (Fujian). Photos by F.-L. Jia.