Velia (Cesavelia) motuoensis sp. nov.

Figs 1 c, d, 2 c, d, i, j, 3 b, 4 c, d, i, j, n, r, s

Material examined.

Holotype: apterous ♂, China • Xizang Province, Linzhi City, Motuo County, Motuo Village: 29.3051°N, 95.3567°E; 1936 m a. s. l.; 2024-VIII-20; Zezhong Jin, Zihe Li leg. (NKUM) . Paratypes: 1 apterous ♂, 3 apterous ♀, same data as holotype (NKUM) .

Diagnosis.

Body large (length 6.90–7.10, width 2.00–2.25), mainly brown. Connexiva of apterous female slightly curved, convergent posteriorly in dorsal view, with orange stripes along connexiva in both sexes (Figs 1 c, d, 2 c, d, i, j), connexival spines sharp and caudally directed in males, dorso-caudally directed in females (Fig. 2 c, d, i, j); abdominal segment VIII of male stout and ventrally concave (Fig. 4 c, d); proctiger of male broad, shield-shaped, posterior margin rounded (Fig. 4 i); paramere broad, strongly curved, with thick setae on external side, apices sharp (Fig. 4 n); endosoma of male stout, lateral sclerites large, strongly sclerotized, apical ends of lateral sclerites distinctly constricted, dorsal sclerites distinctly sclerotized, translucent and curved, with membranous parts medially, secondary ventral sclerite stout, accessory sclerite absent (Fig. 4 r, s); proctiger of female broad, diamond-shaped, lateral dilations distinct (Fig. 4 j).

Comparative notes.

Velia (Cesavelia) motuoensis sp. nov. is most similar to V. longiconnexiva in appearance. It can be distinguished from other species of Cesavelia by the following characters: the absence of the accessory sclerite in the male endosoma distinguishes this species from V. tomokunii, V. championi, and V. mitrai (Fig. 4 r, s); the shape of the male proctiger (Fig. 4 i) distinguishes this species from V. bui, V. longiconnexiva, V. anderseni, V. laticaudata, and V. yunnana; and the characteristics of the endosomal sclerites, especially the large lateral sclerites and dorsal sclerites with membranous parts medially, distinguish this species from V. sinensis, V. tonkina, V. lii sp. nov. and V. yiliangensis sp. nov. (Fig. 4 r, s vs. Fig. 4 p, q, t, u). The extensor sides of the meso- and metatibia without long, erect setae and the shape of the female proctiger (Fig. 4 j) distinguish this species from V. steelei .

Description.

Apterous male (holotype). Measurements. Body: length 6.90 (6.90–7.10), width 2.00 (2.00–2.13). Head: length 0.70, width: 1.15. Antenna: 5.43 (1.89 + 1.27 + 1.20 + 1.07), length of antennal segment I about 1.64 times head width. Pronotum: width about 1.12 times its length (length 1.50, width 1.68). Lengths of leg segments (femur: tibia: tarsus (tarsal segment I + segment II segment III)): fore leg: 2.50: 2.27: (0.09 + 0.24 + (segment III missing)); middle leg: 3.30: 3.50: 2.13 (0.13 + 1.16 + 0.84), length of mesotarsus II about 1.38 times length of mesotarsus III; hind leg: 3.25: 3.55: 1.99 (0.12 + 1.07 + 0.80), maximum width of metafemur: 0.51, length of metatarsus II about 1.34 times length of metatarsus III.

Color (Figs 1 d, 2 i, j). Body mainly dark brown, with scattered silvery pubescence. Pronotum with a row of black punctures near anterior margin and other punctures scattered on posterior lobe. Median part of anterior pronotal lobe dark orange. Sides of abdomen dark brown, with bright orange stripes along connexival segments II – VI, the width of stripes exhibits intraspecific variations; in some samples, the stripes almost cover the entire connexiva. Silvery pubescence usually distinctly denser on anterolateral corners of pronotum, lateral corners of metanotum, lateral parts of abdominal mediotergites II, V – VI, sparse on abdominal mediotergite I and lateral parts of sternites.

Structure. Body relatively large, covered with dense, short pubescence. Head (Figs 1 d, 2 i, j): triangular, almost perpendicular to thorax, without deflection; anteclypeus and postclypeus with dense, peg-like setae; antennal sockets prominent, antennal segment I much longer than head width, slightly thicker than antennal segments II – IV. Thorax (Figs 1 d, 2 i, j): pronotum slightly wider than length, posterior margin of pronotum broadly rounded, lateral parts of pronotum distinctly constricted at mid-length, middle part slightly raised and lateral parts of anterior pronotal lobe concave; mesonotum completely hidden beneath pronotal lobe and hind part of metanotum visible in dorsal view; lateral evaporatoriums slender, with a cluster of suberect, thick setae on each side; legs mainly with decumbent or suberect setae, tarsi of fore legs short, tarsi of middle and hind legs long and slender; profemora moderately incrassate, slightly curved and contracted subapically; mesofemora slender; metafemora (Fig. 3 b) relatively slender, ventrally with two rows of small teeth and two prominent long teeth, the sub-apical tooth almost as long as the sub-basal one, metatibiae ventrally with two rows of small spines. Abdomen (Figs 1 d, 2 i, j): relatively slender; mediotergite I concave laterally, mediotergites II – VII almost flat; connexiva moderately raised, almost parallel, hardly converging, connexival spines short, sharp, caudally pointed; abdominal segment VIII (Fig. 4 c, d) relatively stout, ventrally concave in lateral view, posteriorly with short, sparse setae, posterodorsal margin of abdominal segment VIII medially emarginate. Genital segments (Fig. 4 i, n, r, s): relatively large and visible in vitro; proctiger (Fig. 4 i) shield-shaped, hind margin rounded, posterior with short, sparse setae; paramere (Fig. 4 n) broad, strongly curved, with thick setae on external side, apices sharp; endosoma (Fig. 4 r, s) stout, lateral sclerites large, strongly sclerotized, apical ends of lateral sclerites distinctly constricted, dorsal sclerites distinctly sclerotized, translucent and curved, medially with membranous parts, secondary ventral sclerite stout, accessory sclerite absent.

Apterous female. Measurements. Body: length 7.00–7.10, width 2.20–2.25. Head: length 0.82, width: 1.16. Antenna: 4.97 (1.71 + 1.11 + 1.07 + 1.08), length of antennal segment I about 1.47 times head width. Pronotum: width about 1.09 times its length (length 1.68, width 1.83). Lengths of leg segments (femur: tibia: tarsus (tarsal segment I + segment II + segment III)): fore leg: 2.35: 2.05: 0.82 (0.09 + 0.24 + 0.49); middle leg: 3.17: 3.40: 2.02 (0.11 + 1.11 + 0.80), length of mesotarsus II about 1.39 times length of mesotarsus III; hind leg: 3.15: 3.55: 1.94 (0.13 + 1.04 + 0.77), length of metatarsus II about 1.35 times length of metatarsus III.

Color (Figs 1 a, 2 a, b). Similar to apterous male with following exceptions: silvery pubescence denser on lateral parts of abdominal mediotergite I and laterotergites I (Fig. 2 c). The width of stripes on connexiva exhibits intraspecific variations, wider and brighter in one sample.

Structure. Body slightly larger than apterous male. Head (Figs 1 c, 2 c, d): Similar to apterous male. Thorax (Figs 1 c, 2 c, d): similar to apterous male with following exceptions: profemora slender; metafemora slender, ventrally with two rows of small spines, metatibiae ventrally with some sparse small spines. Abdomen (Figs 1 c, 2 c, d): similar to apterous male with following exceptions: relatively stout; connexiva gradually convergent towards abdominal apex, connexival spines long, slender and straight, dorso-caudally directed. Genital segments: gonocoxae and gonapophyses semi-membranous, rami strongly sclerotized; proctiger (Fig. 4 j) broad, diamond-shaped, lateral dilations distinct, posteriorly with short, sparse setae.

Macropterous female and macropterous male.

Unknown.

Etymology.

This species is named after its type locality, Motuo Village, Motuo County, China.

Habitats.

This species is found in the nearshore areas of larger, slow-flowing streams, particularly in corners formed by deadwood or vegetation. (Fig. 5 b).

Distribution.

China (Xizang) (Fig. 6).