Grouvellinus hongkongensis, Bian & Jäch, 2019

Bian, Dongju & Jäch, Manfred A., 2019, Revision of the species Grouvellinus Champion, 1923 (Coleoptera: Elmidae) with long median pronotal carina, including descriptions of four new species from China, Zootaxa 4586 (1), pp. 127-140 : 128-129

Grouvellinus hongkongensis sp. nov.

( Figures 1 C–D, 5A–C, 9A–C)

Type material: Holotype male ( NMW): “ HONGKONG (7) [ CWBS 8 ] 1992 \ N.T.- Tai Po N.Res. \ 27.VI. leg. Jäch ” . Paratypes: 1 male, 1 female ( IAECAS), 16 exs. ( NMW): same data as holotype; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 13.9.1977 \ leg. Dudgeon (K5)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \

29.9.1977 \ leg. Dudgeon (K5)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 29.9.1977 \ leg. Dudgeon (3)”; 2 exs. ( NMW): “ HONGKONG Tai Po Kau \ 3.10.1977 \ leg. Dudgeon (K5)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 27.10.1977 \ leg. Dudgeon (K5)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 24.11.1977 \ leg. Dudgeon (2)”; 2 exs. ( NMW): “ HONGKONG Tai Po Kau \ 11.12.1977 \ leg. Dudgeon (K5)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 22.12.1977 \ leg. Dudgeon (K5)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 5.1.1978 \ leg. Dudgeon (K)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 19.1.1978 \ leg. Dudgeon (K)”; 1 male ( NMW): “ HONGKONG Tai Po Kau \ 16.2.1978 \ leg. Dudgeon (K)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 2.11.1978 \ leg. Dudgeon (K)”; 2 exs. ( NMW): “ HONGKONG Tai Po Kau \ 30.11.1978 \ leg. Dudgeon (K)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 2.1.1979 \ leg. Dudgeon (K)”; 2 exs. ( NMW): “ HONGKONG Tai Po Kau \ 18.1.1979 \ leg. Dudgeon (K)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 22.2.1979 \ leg. Dudgeon (K)”; 1 ex. ( NMW): “ HONGKONG Tai Po Kau \ 8.3.1979 \ leg. Dudgeon (K)”; 1 male ( IAECAS), 2 exs. ( NMW): “ HONGKONG , 1977-1979 \ Benthic coll. \ Tai Po Kau \ leg. Dudgeon ”; 1 ex. ( NMW): “ HONGKONG , 1977-1979 \ Benthic coll. \ Lam Tsuen River \ leg. Dudgeon ”; 2 exs. ( IAECAS, NMW): “ HONGKONG (4) [ CWBS 5 ] 1992 \ N.T.- Lam Tsuen Riv . \ 25.VI. leg. Jäch ”; 1 male ( NMW): “ HONGKONG (6) [ CWBS 7 ] 1992 \ Lantau Island \ 26.VI. leg. Jäch ”; 1 female ( NMW): “ CHINA: Guangdong Prov. \ 60 km E Fengkai \ 23°26′36″N 111°58′10″E \ 1.11.2001, ca. 230 m \ Jäch & Komarek ( CWBS 458 )”; 3 males, 2 exs. ( NMW): “ CHINA: Guangdong Prov. \ Huashi Shan \ 24°40′28″N 113°56′33″E \ 8.11.2001, ca. 480 m \ Jäch & Komarek ( CWBS 484 )”; 2 exs. ( NMW): “ CHINA, Guangxi 1993 \ Dist. Lipu \ 120km S Guilin \ Berge bei [mountains near] Siuren | 12.11., 350m \ leg. Schönmann et \ Schillhammer (19) [ CWBS 41 ]”; 2 males ( IAECAS, NMW): “ CHINA, SE-Guangxi \ Distr. Yulin \ Liuwan Mts. SW Yulin | 16.11.1993 \ 350-400m \ leg Schönmann (20) [ CWBS 42 ]”; 1 female ( IAECAS): “ CHINA: SE-Guangxi \ Distr. Yulin \ Liuwan Mts. SW Yulin | 17.11.1993, Kuishan, 600-700m \ leg. Schillhammer (21) [ CWBS 43 ]”.

Diagnosis. This species can be distinguished from Grouvellinus bishopi mainly by the median pronotal carina being more strongly elevated, and by its smaller aedeagus; from G. longiusculus it can be distinguished by the aedeagus being smaller and less distinctly curved in lateral view; from G. mediocarinatus it can be distinguished by the apex of the penis being narrowly instead of broadly rounded; from G. robustus it can be distinguished by its slim and small body, and by the apex of the penis being narrowly rounded.

Description. BL ca. 1.85–2.20 mm, BW ca. 1.05–1.10 mm. Body elongate obovate.

Dorsal surface brown to black, labrum paler brown. Ventral surface brown to dark brown. Antennae yellowish brown.

Head: Labrum smooth and microreticulate posteriorly, sparsely micropunctate and pubescent anteriorly. Clypeus and frons densely granulate and sparsely pubescent.

Pronotum ( Figure 5A ): PL ca. 0.60 mm, PW ca. 0.75 mm. Pronotum subparallel in basal 2/5, anteriorly distinctly attenuate. Sublateral carina present in basal 2/5, median carina present in basal 0.8. Disc densely micropunctate/microgranulate, often glabrous basally, moderately densely pubescent, sublateral area densely granulate.

Elytra: EL ca. 1.50 mm, subparallel in basal 2/3, then tapering to more or less subacute apex. Strial punctures large and deeply impressed, punctures separated by 0.5–1.0 times of their diameters in basal half. Punctures smaller and more widely separated in distal half (about 2–4 times of their diameters). Strial intervals 3, 5, 7, 8 with granulated carinae; carina of interval 3 extending from base to declivity. Remaining intervals smooth and shining, sparsely pubescent; interval 1 more densely pubescent.

Prosternum densely granulate and pubescent at sublateral portion; prosternal process with flat disc, sparsely granulate and pubescent, sides distinctly rimmed, apex broadly rounded. Metaventrite broadly impressed at posterior 3/4 medially; disc coarsely and densely granulate and sparsely pubescent; sublateral portion densely granulate; laterally with an oblique row of large punctures, and with a deep transverse groove at anterior and posterior margin. All ventrites densely granulate and sparsely pubescent.

Male genitalia ( Figure 9 A–C): ca. 0.57 mm long. Penis distinctly longer than phallobase, distinctly exceeding parameres, in ventral view distinctly tapering from base to apex, which is narrowly rounded; ventral sac weakly developed. Parameres in ventral view broad in basal 0.1, narrow in basal 0.2–0.9, distinctly narrowed in distal 0.1, distal half of inner edge of parameres densely covered with moderately long setae.

Distribution. China ( Hong Kong, Guangdong, Guangxi).

Etymology. This species is named after Hong Kong (type locality).

Figures

FIGURE 1. Habitus. A–B) Grouvellinus bishopi, paratype male; C–D) Grouvellinus hongkongensis, paratype male. A, C) in dorsal view; B, D) in ventral view.

FIGURE 5. Grouvellinus hongkongensis. A) anterior part of body, dorsal view; B) same, ventral view; C) posterior part of body, ventral view.

FIGURE 9. Aedeagus. A–C) Grouvellinus hongkongensis; D–F) G. longiusculus; A, D) in ventral view; B, E) in dorsal view; C, F) in lateral view. Scale: 0.2 mm.