Broscosoma valainisi Barševskis, 2010

Broscosoma valainisi Barševskis, 2010 View in CoL

Material examined.

- 1 ♂, 1 ♀ ( CZCL), labelled :

“ CHINA: Shaanxi Province, Baoji City, Meixian County, Tangyu Town” //

“ Mt. Taibai , alt= 3146m, E107.810255°, N34.004495° ” // GoogleMaps

“ 2022.VIII.05, Ze-Chuan Li, Sheng-Tong Jin, Jia-Heng Chen & Yi-Chuan Liu lgt.”;

Thierry Deuve (Muséum national d'Histoire naturelle ( MNHN), Paris - Institut de Systématique, Évolution, Biodiversité ( ISYEB), UMR 7205 - France)

- http://zoobank.org/author/ C7BECD5C-FCEA-4A92-BF7B-C3D470D89FBE

- 1 ♀ ( NJAU), labelled :

“ CHINA: Shaanxi Province, Baoji City, Meixian County, Tangyu Town” //

“ Mt. Taibai , alt= 3220m, E107.807600°, N34.000987° ” // GoogleMaps

“ 2022.VIII.05, Ze-Chuan Li, Sheng-Tong Jin, Jia-Heng Chen & Yi-Chuan Liu lgt.”.

Re -description

Medium size . – BL 11.4–12.1mm.

Coloration. – Body blackor dark brown, dorsum shiny, withoutmetallic reflections, antennae,femora, tibiae and tarsi dark brown (Figure 1).

Head ( Figure 2A). – Head convex, dorsal surface shiny and impunctate; frontal grooves irregular, deep and pair smooth of setae,; extending one pair of toward supraorbital posterior setae margin present of; eyes vertex; anterior lacking margin punctures of clypeus, post-temporal nearly straight transverse, with sulcus one almost invisible; tempora almost flat or just faintly convex; antennomeres I–IV glabrous, V–XI pubescent.

Pronotum ( Figure 2A). – Dorsal surface shiny, microsculpture absent; disc mightily convex, anterior disc to sub-basal constriction slightly longitudinally ovoid (PL/PW 1.23–1.28); anterior impression quite shallow and smooth, median longitudinal impression distinct, posterior impression deep; anterior margin and discal area smooth and impunctate, basal portion rugous but not coarse in dorsal view; one pair of mid-lateral setae located at anterior middle of pronotum; basolateral setae absent.

Elytra ( Figure 2B). – Ovoid (EL/EW 1.54–1.59), mightily convex; dorsum shiny, microsculpture absent; shoulders strongly narrow and rounded; lateral margin visible at humeral area and posterior one-

second in dorsal view; eight striae shallow, punctate, but distinctly present, striae Ⅰ–III relatively deeper,

striae IV–VIII shallower and almost represented by punctures, stria VIII shallow but distinct, never merged with lateral groove; parascutellar seta located at base of interval II, close to striaII; without disc setae; umbilicate series of each elytron composed of four pores, one pore present just behind shoulder, one pore present at posterior one fourths of the body length, and two located at elytral apex.

Male genitalia ( Figure 2C–E). – Median lobe of aedeagus simple, moderately stubby and curved, apical lamella short, apex obtuse and gradually bent downwards in lateral view, never expanded or sinuate before tip; right paramere arcuate, apex slightly expended and rounded, with dense long setae along apical margin;

left paramere expanded at middle portion, apical portion markedly narrow and apex acute, without setae.

Differential diagnosis. – Moderate size (BL 11.4–12.1mm); entire dorsum shiny, dorsal surface dark brown to black, without metallic reflections; head with tempore nearly straight or just slightly convex behind eyes; vertex impunctate, post-temporal transverse sulcus almost invisible; pronotum anterior to sub-basal constriction slightly longitudinally ovoid, each side with only one mid-lateral seta and one basolateral seta, dorsal microsculpture absent, pronotal base moderately rugous; elytra ovoid, humeri strongly narrowed and rounded, elytral striae shallow, only stria Ⅰ to III relatively impressed, the others indistinct or nearly represented by punctures, stria VIII present, never merged with lateral groove; median lobe of aedeagus relatively stubby, apical lamella short with apex gradually rounded and bent downwards in lateral view, right paramere rounded at apex, left paramere apically acute and narrow, without setae.

B

This. zhengyuandongi species is most Jiang similar, Feng to four & Wang known, 2020 species, B. guoliangi : B. xuhaoi Jiang Jiang, Liu, Feng & Wang & Wang, 2021 , 2020 and,

B. qiului Jiang, Liu & Wang, 2021 View in CoL , which are recognizable among congeners by the combination of:

(1) vertex with post-temporal transverse sulcus shallow and impunctate;

(2) tempora almost flat or just faintly convex;

(3) shoulders indistinct and largely narrow;

(4) all eight elytral striae completely present and stria VIII not merged with lateral groove;

(5) elytra microsculpture absent;

(6) median lobe of aedeagus relatively stubby, apical lamella short and evenly curved at apex, never expanded before tip.

From the external, B. valainisi is especially similar to B. xuhaoi , but can be distinguished by:

(1) clypeus with just one pair of setae (versus two pairs present in B. xuhaoi );

(2) pronotal base wrinkled but not coarse (versus absolutely smooth in B. xuhaoi );

(3) elytral silhouette more elongated, EL/EW 1.54–1.59 (versus 1.41–1.42 in B. xuhaoi );

(4) elytral striae obviously shallower;

(5) median lobe of aedeagus more curved;

(6) apex of left paramere sharply acute, without setae (versus more obtuse, with present apical setae in B. xuhaoi ).

Figure 1. Broscosoma valainisi Barševskis, 2010 .

Comparing to B. qiului , B. valainisi is different in:

(1) pronotum more elongated, PL/PW 1.23–1.28 (versus 1.14 in B. qiului );

(2) pronotal base wrinkled but not coarse (versus absolutely smooth in B. qiului );

(3) legs always dark brown, while reddish or yellowish brown in B. qiului ;

(4) apex of aedeagus more rounded and obtuse, superior margin before tip less sinuate and more smoothly curved in lateral view;

(5) apex of left paramere sharply acute (versus ending in a more rounded tip in B. qiului );

(6) apex of right paramere rounded and expanded (versus acute and narrow in B. qiului ).

As for two other species: B. zhengyuandongi and B. guoliangi , B. valainisi can be readily distinguished by:

(1) pronotal base wrinkled (versus absolutely smooth in the latter two);

(2) elytra more elongated, EL/EW 1.54–1.59 (versus 1.33–1.43); (3) elytral striae distinctly shallower;

(4) median lobe of aedeagus slenderer;

(5) apex of left paramere more sharply acute;

(6) apex of right paramere rounded and expanded (right paramere not expanded near apex in the latter two).

Bionomics ( Figure 3). – All adults were collected on the surface of wettish and mossy stones in an area of Larix forest on the north-facing slope just below the crest of the range at night. This species has been found only at moderately high elevations in the 2000 to 3300 m range.

Distribution ( Figure 4). – Only known from Taibai Mountains in Shaanxi Province.

Remarks. – Broscosoma valainisi is morphologically similar to several species from eastern China ( B. zhengyuandongi Jiang, Feng & Wang, 2020 and B. guoliangi Jiang, Liu & Wang, 2021 from Fujian; B. uenoi Habu, 1972 from Taiwan) and from western China ( B. xuhaoi Jiang, Feng & Wang, 2020 and B. qiului Jiang, Liu & Wang, 2021 from Chongqing; B. dostali Deuve, 2006 , B. herculeanum Deuve, 2011 and B. mourzinei Deuve, 2011 from Sichuan; B. furvum Kavanaugh & Liang, 2021 from Yunnan) in body without dorsal metallic reflections and elytra with narrow shoulders. B. valainisi was originally described based on female adult, we firstly describe and illustrate its male genitalia herein. Consequently, we propose that it is closer to B. xuhaoi , B. zhengyuandongi , B. guoliangi and B. qiului than the others, based on the following characteristics: forebody dorsally impunctate (versus more or less punctate); stria VIII distinct (versus merged with lateral groove); median lobe of aedeagus stubby, gradually narrow before apex (versus slender, distinctly expended before apex). These five species are strictly allopatric and very narrowly distributed, however, distributions of western species ( B. valainisi , B. xuhaoi and B. qiului ) and eastern species ( B. zhengyuandongi and B. guoliangi ) are separated by a blank area, it may mean that there are more related species awaiting to be discovered.