Paratrichius pilosus Ricchiardi & Lu

Ricchiardi, Enrico, Lu, Yuanyuan, Li, Sha & Ming, Bai, 2022, Notes on Paratrichius Janson, 1881 inhabiting Hainan Island, with description of a new species and the definition of two new junior synonyms (Coleoptera: Scarabaeidae, Cetoniinae), Fragmenta entomologica 54 (1), pp. 133-142 : 139-141

Paratrichius pilosus Ricchiardi & Lu , new species

Type series. HT ♂, 3PT ♂, 3PT ♀ IZAS, China: Hainan. HT ♂ Lingshui, Diaoluoshan Waterfall , 580 m, 10 May 2011, (IOZ(E)1945059), Lin Wenxin legit . 1PT ♂, Hilltop of Jianfengling , 25 Apr 1983, IOZ(E)901343, Gu Maobin legit . 1PT ♂, Lingshui, Mt.Diaoluoshan , 960-970 m, 6/ 7 May 2011, IOZ(E)1945056, Lin Wenxin legit . 1PT ♂, same data but 960 m, 8 May 2011, IOZ(E)1945058. 2 PT ♀, Lingshui, Diaoluoshan road to waterfall, 580-960 m, 9/ 19 May 2011, IOZ(E)1945724 and IOZ(E)1945723, Lin Wenxin legit . 1PT ♀, Jianfengling , 11 May 1981, IOZ(E)901354, Chen Zhiqing legit .

Description of holotype ♂

General. Length 12.1 mm, maximum elytral width 4.9 mm. Elongate, with slender legs. Black, except scapus, segments and the internal lamella which are dark-fulvous.

Body decorated with pale-yellow chalky markings as follows: pronotum with a chalky narrow band along margins, interrupted at around one-third of length at lateral ones and at central part of posterior margin. With a longitudinal narrow, short band at middle, two chalky spots on the sides. Elytron with chalky juxtascutellar margins and six prominent, chalky spots positioned in two angulate rows, at one-third and two-thirds of length. The two spots on declivity are elongated. Pygidium with a large comma-shaped patch at each side. Tergites side of ventrites 2-4 covered with chalky material, that of ventrite 5 without such material. Ventral side of ventrites 2-5 covered with chalky material. Ventrites 2-5 with lateral sides without chalky material. Ventrite 6 (anal one) with centre covered with chalky material.

Head. Clypeus shiny, glabrous, wider than long (width about 1.1 times length), widest at centre, sides regularly rounded outwards up to two third of length from anterior margin; horizontally arched, anterior corners rounded, an- terior margin emarginate, not reflexed, sinuate. Surface of clypeus apex widely minutely punctulate. Disc of clypeus and frons reticulate. Antennal club long about 1.5 times the clypeus length.

Pronotum. Octagonal. Surface imbricate. Slightly wid- er than long (about 1.1 times wide than long), moderately convex, with a short, shallow, central, longitudinal hollow of about one-thirds of length, with two large, shallow depressions at sides. Lateral margins broadly rounded laterally and posteriorly, anterior angles obtuse, posterior angles widely rounded, posterior margin broadly emarginated mesad. Covered with thick, fulvous, slightly long setae at anterior margin and corners.

Scutellum. Matt, with scattered punctures.

Elytron. Intervals covered with scattered, short, erect fulvous setae and scattered punctures. Striae prominent, with shallow horse-shoe punctures, and posterior portion of juxtasutural interval reticulate.

Pygidium. Convex, slightly wider than long (maximum width about 1.15 times maximum length), with apex rounded. Surface imbricate. Covered with very scattered, short, recumbent, fulvous setae.

Ventrites. With noticeable, central, longitudinal hollow. Mostly covered with long, erect, fulvous setae.

Legs. Protibia bidentate, lacking terminal spur. Meso- and Metatibia posterior margin central tooth obsolete. Metatarsomeres 3-5 with long and thick yellowish setae, longer and longer from third to fifth. Metatibia long about 1.2 times the three first tarsomeres combined. First meta- tarsomere slightly longer than second.

Aedeagus. As in Figs 4 L-M.

Description of female (differences from male only).

General. Length about 12.5 mm, maximum elytral width about 4.7 mm. Body stockier than in male, with protibia larger.

Head. Clypeus black, dark fulvous at anterior corners, less arched than in male. Antennomeres mostly dark-fulvous. Antennal club about of same length of clypeus.

Pronotum. Dark fulvous, surface shagreened or reticulate by places. Posterior corners widely rounded, surface dark-fulvous, slightly shiny, reticulate. Pronotal central longitudinal hollow present. With thick, fulvous, moderately long setae on lateral margins and corners.

Elytron. Dark red-brown, matt.

Pygidium. Black, shiny, with large band of yellowish chalky material at sides, reaching anterior and posterior margins, covered with regularly scattered, short, fulvous setae, becoming longer at apex. Surface imbricate, punctuate on apical hollow. Disc deeply hollowed just after mid-point to apex. Ventrites. Black. Superior part of ventrites 2-3 without chalky material, Ventrite 3 with a small chalky spot at sides. Ventrite 4 same chalky spots but much longer and wide. Ventrite 5, centrally completely covered. Anal ventrite (ventrite 6) not hollowed and without chalky material.

Legs. Tibiae dark-fulvous, femurs darker to black. Protibia largely bidentate, with spur. Posterior margin of metatibia with central tooth not very conspicuous, with apex rounded. Tarsi more robust than in male.

Type series variability. The HT ♂ and one PT ♂ are com- pletely black, 2PT ♂ have a completely red-brown prono- tum, elytron, antennal club and legs. 3PT ♀ have completely dark red-brown pronotum, elytron, antennal club, anterior margin of clypeus and legs.

Discussion. Among the species inhabiting Hainan, Paratrichius pilosus n. sp. is morphologically close to P. elegantulus . The latter taxon exhibits shorter yellow brown setae at the apex of metatarsomeres I-V in both sexes, while P. pilosus have longer, yellow brown setae, becoming longer from third to fifth metatarsomeres. In any case, the parameres of the two species are distintive ( Figs 1 K-L and 4 L-M).

Derivatio nominis. The name of the species comes from the long setae that adorn the last three metatarsomeres.

Figures

Fig. 4 – Paratrichius pilosus Ricchiardi & Lu, new species. HT♂ IZAS: A, dorsal habitus; B, ventral habitus; C, lateral habitus; H, pronotum & head; I, pygidium; L, parameres, frontal view; M, parameres, lateral view; PT ♂ IZAS: D, colour variation; PT♀ IZAS: E, dorsal habitus; F, ventral habitus; G, lateral habitus; J, pronotum & head; K, pygidium. Photographs by Yuanyuan Lu.

Fig. 1 – Paratrichius elegantulus (Moser, 1902), material collected in Hainan: ♂ IZAS: A, dorsal habitus; B, ventral habitus; C, lateral habitus; D, head; E, pygidium, K, parameres, frontal view; L, parameres, lateral view; ♀ IZAS: F, dorsal habitus; G, lateral habitus; H, ventral habitus; I, head; J, pygidium. Photographs by Yuanyuan Lu.