Ichthyurus cleriformis Y. Yang, Lin & Liu, 2025

Ichthyurus cleriformis Y. Yang, Lin & Liu sp. nov.

Figs 8 G View Figure 8 , 10 E View Figure 10 , 16 C ‒ D View Figure 16 , 18 E ‒ H View Figure 18 , 19 View Figure 19

Type material.

Holotype. Laos • ♂ ( MHBU), “ Laos, Vientiane, Phone Thong, Hin Herp , 212 m alt., 28. VI. 2015, Haoyu Liu leg. ”

Paratypes. Laos • 17 ♂♂ 6 ♀♀ ( MHBU), “ Phoukhao, NationBio , 29. VI. 2015, Haoyu Liu leg. ” . China, Yunnan • 1 ♀ ( NWAFU), Mengyang , 750 m alt., 6. VI. 1991, Yinglun Wang & Ruigang Tian leg.

Differential diagnosis.

This species can be attributed to the I. bourgeoisi group by the terminal abdominal tergite of male with postero-lateral projections excavated ventrally and arcuately, delimited with edges, which are keeled and hooked terminally (Fig. 19 A, C View Figure 19 vs. Lin et al. (2024 a): figs 10 A ‒ D, 14 A, B), but it can be easily distinguished from other members by the body coloration (Fig. 16 C, D View Figure 16 vs. Lin et al. (2024 a): figs 9, 13) and details in the shape of terminal abdominal ventrite of male (Fig. 19 E View Figure 19 vs. Lin et al. (2024 a): figs 10 E, F, 14 D, E) and female (Fig. 19 F View Figure 19 vs. Lin et al. (2024 a): fig. 12 B, D), as well as aedeagus (Fig. 18 E ‒ H View Figure 18 vs. Lin et al. (2024 a): figs 11, 15).

Description.

Body length (both sexes): 6.9‒7.0 mm (7.0 mm in holotype); body width (both sexes): 1.2‒1.3 mm ( 1.2 mm in holotype).

Male (Fig. 16 C View Figure 16 ). Colouration. Body black, antennomeres I ‒ III yellow, elytra yellowish-orange, with a pair of black rounded markings in middle of disc, legs yellow, except for black tarsi and apical parts of tibiae, abdomen yellow posteriorly and laterally.

Eyes strongly protruding, interocular distance ca. 0.4 times of the diameter of an eye. Antennae extending to elytral apices, antennomere II ca. 1 / 4 length of I, III ‒ XI subequal in length and ca. 3.0 times longer than II.

Pronotum 1.3 times wider than long, anterior margin arcuate, lateral margins strongly arcuate, posterior margin strongly bisinuate, anterior angles feebly emarginate, posterior angles nearly rectangular.

Elytra 1.5 times longer than wide, ca. 2.3 times longer than pronotum, with lateral margins nearly parallel, sutural margins sinuate and moderately dehiscent from the basal 1 / 3 part, distance between sutural margins twice as wide as apical width of an elytron, apices rounded.

Pro- and mesofemora (Fig. 16 C View Figure 16 ) slightly swollen, metathoracic legs slender and simple.

Terminal abdominal tergite (Fig. 19 A, C View Figure 19 ) ca. 1.5 times longer than wide, with postero-lateral projections ca. 2 / 5 length of the tergite, distinctly arcuate at both inner and outer margins, excavated ventrally and arcuately, delimited with edges, which are keeled and feebly hooked terminally (Fig. 19 A View Figure 19 ). Proctiger (Fig. 19 C View Figure 19 ) triangular and evenly sclerotised, completely surrounded by paraproct; paraproct (Fig. 19 C View Figure 19 ) strongly developed and tubular, feebly shrunk apically, deeply emarginate in middle of dorso-posterior margin, tergal flange (destroyed and missing).

Terminal abdominal ventrite (Fig. 19 E View Figure 19 ) inverted trapezoidal, ca. 1.3 times as long as wide, largely and rectangularly emarginate in middle, with middle emargination as deep as 1 / 3 length of the ventrite, outer apical angles rounded at apices, longitudinally and arcuately ridged near middle and on both sides, transversely and arcuately ridged near outer apical angles.

Abdominal sternite IX (Fig. 8 G View Figure 8 ) moderately sclerotised and subparallel-sided, ca. 3.0 times longer than wide, with posterior margin obliquely truncate, posterior right angle narrowly triangular and left angle widely triangular, anterior left angle small beak-shaped and right angle strongly protruding anteriorly, moderately expanded and boot-shaped at apex.

Aedeagus (Fig. 18 E ‒ H View Figure 18 ): right paramere dorso-ventrally flattened, feebly bent, obtuse beak-like at apex (Fig. 18 E, H View Figure 18 ), approximately twice as long as wide; left paramere dorso-ventrally flattened, bifurcate near apex, with inner branch acute at apex and much longer than outer one, feebly shorter than right paramere (Fig. 18 F, G View Figure 18 ); setifore extension strongly sclerotised, stout and short, 1 / 3 length of left paramere (Fig. 18 E ‒ G View Figure 18 ); median lobe 3.0 times as long as tegmen, strongly narrowed basally (Fig. 18 E, H View Figure 18 ).

Female (Fig. 16 D View Figure 16 ). Similar to males, but body larger, eyes less protruding; terminal abdominal tergite (Fig. 19 B, D View Figure 19 ) ca. 1.2 times longer than wide, with postero-lateral projections ca. 2 / 5 length of the tergite; terminal abdominal ventrite (Fig. 19 F View Figure 19 ) unevenly sclerotised and weaker on both sides, ca. 1.2 times as long as wide, widest near middle, rounded at lateral margins and confluent with outer apical angles, shallowly and roundly emarginate in middle of posterior margin. Internal organ of the reproductive system (Fig. 10 E View Figure 10 ): bursa copulatrix tail-shaped at apex; accessory gland even in width at apical half part.

Etymology.

The specific name is derived from the Latin - formis (- like), referring to its similarity to some Cleridae species in the appearance.

Distribution.

China ( Yunnan), Laos.