Grouvellinus fujianensis, Bian & Jäch, 2018

Bian, Dongju & Jäch, Manfred A., 2018, Revision of the Chinese species of the genus Grouvellinus Champion, 1923 (Coleoptera: Elmidae). The G. acutus species group, Zootaxa 4387 (1), pp. 174-182 : 177-181

Grouvellinus fujianensis sp.nov.

( Figs 5–8 , 15–17 )

Type material: Holotype ( IAECAS), male: “ CHINA: FUJIAN, Yong'an \ 4 km SW Xiyang, 400m \ Ziyungdong Shan , 25.1.1997 \ leg. H.Schönmann ( CWBS 257 )” . Paratypes: 1 male ( NMW): same label data as holotype; 1 male ( NMW): same label data as holotype except “leg. Ji & Wang ”; 2 males ( NMW): “ CHINA: FUJIAN, Yong'an \ 2 km SW Xiyang, 350m \ Ziyungdong Shan , 24.1.1997 \ leg. H.Schönmann ( CWBS 254 )”; 1 male ( NMW): same label data except “leg. Ji & Wang”; 1 male ( NMW): “ CHINA, SE-Guangxi \ Distr. Yulin \ Liuwan Mts. SW Yulin ǀ 16.11.1993 \ 350–400m \ leg. Schönmann (20) [= CWBS 42 ]”; 1 male ( IAECAS): “ CHINA: SE-Guangxi \ Distr. Yulin \ Liuwan Mts. SW Yulin | 17.11.1993 \ Kuishan, 300m \ leg. Schönmann (22) [= CWBS 44 ]”.

Diagnosis. Males of Grouvellinus fujianensis can be distinguished externally from males of G. acutus by the lack of distinct admedian carinae on the metaventrite, and by the absence of distinct secondary sexual characters on the hind tibia. It differs from G. denticulatus by the less broadly impressed metaventrite. From both species it is readily distinguished by the aedeagus (see Key below).

Description. Head and pronotum black, elytra black with ferrugineous or yellowish-brown markings on base and declivity; in specimens from Guangxi, these spots are more or less connected with each other between suture and interval 5 ( Fig. 7 ). Ventral surface dark brown, legs dark brown except tarsi. Antennae and tarsi yellowishbrown.

BL: 1.60–1.75 mm, BW: 0.80–0.90 mm. Body obovate ( Figs 5–8 ).

Head densely granulate and pubescent, clypeus with granules sparser than on frons, sparsely pubescent on disc, but densely pubescent laterally. Labrum smooth and shining, sparsely punctate and pubescent on disc, densely pubescent laterally.

PL: 0.48–0.51 mm, PW: 0.62–0.66 mm, broadest at basal 0.4, then slightly narrowed towards anterior corners. Surface partly densely granulate, pubescent. Sublateral carina present on basal 0.3; oblique impression extending from apex of carina to anterior angles. Base with pair of small oval impressions in front of anterior angles of scutellum.

EL: 1.12–1.24 mm, subparallel in basal 2/3, tapering to apex. Strial punctures moderately large, punctures becoming finer and widely separated on distal half. Non-carinate intervals slightly convex or almost flat, each with a row of setae; in specimens from Fujian these intervals usually more or less strongly wrinkled.

Prosternal process flat, densely granulate, with truncate apex. Metaventrite narrowly impressed along median suture; without distinct admedian carinae; median area densely granulate, covered with some very large punctures; sublateral area densely granulate and sparsely pubescent, with oblique row of very large punctures. All ventrites densely granulate and sparsely pubescent except posterior margins of ventrites 2 – 4 densely pubescent. Hind tibia without obvious sexual dimorphism.

Aedeagus ( Figs 15–17 ): 0.51–0.53 mm long, robust, penis slightly narrowed from base towards basal 3/5, then distinctly narrowed towards apex, ventral sac weakly developed. Penis slightly longer than parameres. In lateral view, parameres rather narrow, with some long setae especially in apical part.

Female: In all females, which were collected together with the holotype and the paratypes (see below, under Discussion), the metaventrite is less deeply grooved than in the males.

Distribution. So far known only from Fujian and Guangxi ( China).

Etymology. This species is named after Fujian Province, China.

Figures

FIGURES 5–8. Habitus, 5–6 dorsal and ventral view of Grouvellinus fujianensis sp.nov., male, holotype, Fujian; 7–8 dorsal and ventral view of G. fujianensis sp. nov., male, paratype, Guangxi. Scale bar= 0.5 mm.

FIGURES 15–17. Male genitalia of Grouvellinus fujianensis sp. nov., holotype, 15 ventral view, 16 dorsal view, 17 lateral view. Scale bar = 0.1 mm.