Lacconectus brancuccii, Hájek, Jiří, Zhao, Shuang & Jia, Fenglong, 2013

Hájek, Jiří, Zhao, Shuang & Jia, Fenglong, 2013, The Lacconectus Motschulsky of Hainan, China, with description of a new species (Coleoptera: Dytiscidae: Copelatinae), Zootaxa 3693 (1), pp. 91-96 : 92-93

Lacconectus brancuccii sp. nov.

( Figs. 1–4 )

Type locality. China, Hainan Island, Limushan Mts., ca. 19°11ʹN, 109°44ʹE.

Material examined. Holotype ♂, labelled: “ China, Hainan / Limushan, Zhufeng / (the highest peak) / 6. v. 2011 / Zhao Shuang lgt. [printed]”, “ HOLOTYPE ♂ / LACCONECTUS / brancuccii sp. nov. / J. Hájek & F. Jia det. 2013 [red label, printed]” (SYSU). Paratypes: 7♂ 5♀, same label data as holotype (BMHN, NHMW, SYSU); 10♂ 11♀, labelled: “ CHINA, HAINAN Isl., 6.v.2011 / Limushan Mts., mountains / above frst. [= forest] admin. centre / 19°10.5-10.9ʹN, 109°44-45ʹE / M. Fikáček leg., 650–690 m [printed]” (BMNH, NMNPC); 8♂ 7♀, labelled: “ China, Hainan / Jianfengling, the / third and the fifth / district / 9. v. 2011 / Zhao Shuang lgt. [printed]” (NMPC, SYSU); 4♂ 4♀, labelled: “ CHINA, HAINAN Isl., 10.v.2011 / Jianfengling Mts., Tianchi Lake env. / rd from TIANCHI vill. to “sector 5”, / 18°43.6-44.1'N, 108°52.1-5'E; / M.Fikáček & S.Zhao leg., 820–950 m // pools in and at shaded / drying-up stream in / primary forest [printed]” (NMPC). Each paratype is provided with the respective red printed label.

Description of holotype. Medium sized, ovate species; body distinctly arched in lateral view. Shiny. TL: 4.6 mm; TL-h: 4.2 mm; TW: 2.7 mm.

Colouration. Head testaceous with broad blackish interocular bands; appendages testaceous. Sides of pronotum testaceous, disc largely irregularly infuscate; basal and anterior margins brown-blackish. Scutellar shield brown-blackish. Elytra testaceous, base (especially in middle of elytra), suture, sutural puncture line and lateral margin brown-blackish; pale yellowish markings of elytra consisting of broad transverse (sub)basal band with sinuous posterior margin, and indistinct lateral posteromedial spot. Legs testaceous. Ventral side of head with testaceous gula, submentum and mentum; genae darker, brown. Prosternum and hypomeron testaceous. Base of elytra testaceous, rest black. Meso-, metaventrite and metacoxae brown-blackish; metacoxal processes somewhat paler. Abdominal ventrites slightly paler than metacoxae, dark brown.

Surface sculpture. Head microreticulate; fine polygonal meshes shallowly impressed, becoming somewhat elongate on vertex. Punctation consisting only of large punctures confined to clypeal grooves and grooves along eyes. Clypeus anteriorly truncate. Antennomeres slender, antennomere V ca. 1.8 times as long as broad. Side of pronotum regularly rounded, narrowly bordered except of anterior angles. Microreticulation similar to that of head except of elongate radially arranged meshes surrounding fine punctures. Punctation of pronotum consisting of coarse setigerous punctures along margins, and fine regularly distributed punctures. Longitudinal groove on centre of disc short, weakly impressed. Microreticulation of elytra very shallow, presented only in basal half; elongate radially arranged meshes surrounding fine punctures. Reticulation persisting as irregular striolation in apical half. Punctation of elytra consisting of very fine regularly distributed punctures and large setigerous punctures arranged as follows: sutural puncture row present only shortly before elytral apex; two discal and lateral puncture rows present in full length of elytra; several punctures present also between discal rows and near elytral apex. Prosternal apophysis ovoid, bordered at sides, apex broadly rounded. Microreticulation of prosternum absent; microreticulation of meso- and metaventrite consisting of fine elongate meshes. Metacoxal plates with microreticulation consisting of very elongate meshes, and with few transverse grooves. Abdominal ventrites microreticulated with elongate meshes, oriented vertically on ventrite I, obliquely in ventrite II and transversally in ventrites III–IV; punctation consisting of very few irregularly distributed fine punctures, and coarse setigerous punctures in middle of ventrites. Apical ventrite with meshes of reticulation less elongate, fine punctures more numerous than on preceding ventrites; posteriorly bordered. Metafemora with rectangular apical posterior angles. Meso-, metatibiae and metatarsi with long natatorial setae.

Male external genitalia. Median lobe of aedeagus in lateral view almost evenly curved, slightly narrowed subapically and then broadened to a rounded apex ( Figs. 2–3 ). Paramere broad ( Fig. 4 ).

Variability. Specimens of types series varying considerably in body colouration, especially in infuscation of pronotum (ranging from almost completely testaceous, to dark pronotum with narrow testaceous sides), width and shape of basal yellowish transverse band, and in size and shape of lateral postero-medial yellowish spot.

Female without conspicuous external differences from male; pro- and mesotarsi not broadened. Valvae long and very narrow, narrowly rounded at apex. Seta short and subapical.

Measurements (N = 18): TL: 4.6–5.3 mm; TL-h: 4.2–4.9 mm; TW: 2.7–2.8 mm.

Differential diagnosis. With the more or less uniformly testaceous elytra with only indistinct pale markings on the basis, uninterrupted discal and sublateral rows of punctures, and median lobe not laterally enlarged in ventral view, the new species can be classified within the Lacconectus fulvescens species group sensu Brancucci (1986). Lacconectus brancuccii sp. nov. differs from the syntopically occurring L. hainanensis by the absence of coarse punctures on the elytra, and from L. maoyangensis by the broader, not well delimited pale basal markings on the elytra. However, the most important character distinguishing the new species from all other members of the genus is the characteristic shape the of median lobe of the aedeagus, which is in lateral view slightly narrowed subapically and then broadened to the rounded apex ( Figs. 2–3 ).

Etymology. The new species is dedicated to the late Michel Brancucci (Basel, Switzerland), our colleague and the specialist on genus Lacconectus ; the specific epithet is a noun in the genitive case.

Collecting circumstances. At the type locality the new species was collected in pools among rocks with a layer of decaying leaves, near a stream flowing in secondary forest; in Jianfengling Mts. the specimens were collected in pools in a shaded drying-up stream in the primary forest (M. Fikáček, pers. comm. 2013).

Distribution. So far known only from two mountain ranges on Hainan Island, China ( Fig. 9 ).

Figures

FIGURE 9. Map of distribution of Lacconectus species in Hainan. Circle— L. brancuccii sp. nov.; square— L. hainanensis; triangle— L. maoyangensis.

FIGURES 1 – 8. Lacconectus from Hainan (Limushan Mts.). 1 – 4. L. brancuccii sp. nov.: 1 — habitus of paratype (3, 5.2 mm); 2 — median lobe of holotype in lateral view; 3 — same of paratype; 4 — right lateral lobe (paramere) of holotype. 5 – 6 L. hainanensis: 5 — habitus (3, 5.3 mm); 6 — median lobe in lateral view. 7 – 8 L. maoyangensis: 7 — habitus (3, 4.8 mm). 8 — median lobe in lateral view. Scale bar = 1 mm (Figs 2 – 4, 6, 8).