Wesmaelia longius Li, sp. n.

(Figs 1 –12)

Type material. Holotype, ♀, Malipo County, Wenshan, Yunnan Province, China, 8. IX. 2017, Yan-Qiong Peng.

Paratypes: 1 ♂, Malipo County, Wenshan, Yunnan Province, China, 15.III. 2017, Yan-Qiong Peng ; 1♀, Malipo County, Wenshan, Yunnan Province, China, 13.VIII. 2017, Yan-Qiong Peng ; 1 ♀, Malipo County, Wenshan, Yunnan Province, China, 30-X-2017, Yan-Qiong Peng ; 1 ♀, Malipo County, Wenshan, Yunnan Province, China, 16-X-2016, Yan-Qiong Peng .

Description. Holotype, ♀, length of body 2.6mm; length of fore wing 1.8mm.

Head. Antenna with 15 flagellomeres, 1.8 × length of head and mesosoma combined; antennal scape short, 1.4 × longer than wide; first flagellomere (including annulus) somewhat longer than second flagellomere; last flagellomere elongate, length of first, penultimate and last flagellomeres 5.5, 2.8 and 4.0 × their width; length of the rest flagellomere about 3.8 × their width (Fig. 2). Head transverse (Fig. 3), 1.8 × as broad as long, strongly rounded behind eyes in dorsal view; median carina between antenna mostly effaced; eyes 1.4 × as long as temple; temple highly polished and mostly devoid of setae, in lateral view distinctly protruding; ocelli small, OOL: OD: POL=11: 3: 6; occipital carina complete and occiput moderately excavated; face in frontal view rectangle, faintly punctate and moderately setose, its width 1.2 × height; eyes ovoid, comparatively converging ventrally; width of clypeus 3.0 × its median height and 1.2 × width of face; distance between tentorial pits 5.0 × as long as shortest distance between tentorial pit and lower margin of eye; maxillary palp 6-segmented, as long as head; malar space narrow, 1.2 × basal width of mandible; mandibles long and slender, nearly completely overlapping when closed (Fig. 4).

Mesosoma. Mesosoma in lateral view 1.3 × longer than high (Fig. 6); pronotum, propleuron and metapleuron mostly sculpture areolate; mesopleuron smooth, precoxal sulcus distinct as a narrow and sculptured furrow (Fig. 6); mesonotum nitid with moderately setae, notauli shallow and wide, finely crenulated; scutellar sulcus with 1 crenulae (Fig. 5); propodeum areolate-rugose, its hind vertical part concave.

Wings. Fore wing shorter than body, length of fore wing 3.1 × its width; length of pterostigma 2.2 × its width and vein r issuing distally from its middle; vein 1-R1 1.4 × as long as pterostigma; SR1+3-SR slightly curved, virtually approaching tip of wing; distal 1/5 of vein R1 and vein SR1+3-SR shortened, so not meeting each other apically; vein r 0.3 × as long as maximum width of pterostigma; 1-SR+M straight; first submarginal cell relatively high, vein 2-SR 2.0 × longer than vein 1-SR + M and 4.0 × as long as vein m-cu; m-cu antefurcal; vein cu-a postfurcal and 1-CU1 longer than cu-a (Fig. 7); r: 2-SR: SR1+3-SR= 2:11: 17; 1-CU1: 2-CU1: 3-CU1= 1: 7: 4. Hind wing 5.0 × as long as wide, vein cu-a of hind wing distinctly distally issuing from middle of M+CU + 1-M (Fig. 7).

Legs. Hind coxa striate. Tarsal claws short and simple. Length of femur, tibia, and basitarsus of hind leg 6.6 ×, 13.0 ×, and 18.0 × longer than wide respectively; hind tibia as long as hind tarsus; the length hind basitarsus 1.2 × the length of tarsomeres 2–4 (Fig. 9).

Metasoma. Metasoma about 1.7 × as long as head and mesosoma combined. Petiolate first metasomal segment exceptionally long and slender, 12.0 × longer than midpoint width in lateral view and as long as the reminder of metasoma except first metasomal segment. In lateral view, petiolate strongly curved view, 2/3 base sculptured, remainder smooth and shiny; spiracles distinct and situated dorsal 1/3 of petiole (Fig. 8); metasoma polished. Ovipositor sheath short, in lateral view 1.9 × length of 3rd segment of hind tarsus (Fig. 10).

Color. Head brown; mesosoma, tegulae, pterostigma and metasoma black brown; antenna, palpi, propleuron, legs and petiolate first metasomal segment yellowish-brown; second and third metasomal segment with black brown suffusion (Fig. 1); wings subhyaline, veins opaque yellowish (Fig. 9).

Male. Similar to female, but antenna shows sexual dimorphism, especially last flagellomeres much shorter. Body 2.1 mm long (Fig. 11). Head in dorsal view transverse,1.4 × broader than long. Eye in lateral view 1.4 × higher than wide, temple less wide than eye. Antenna 16-segmented, 1.8 × length of head and mesosoma combined, surface with more setae; antennal scape shorter, 0.9 × longer than wide, length of fist, penultimate and last flagellomeres 3.3, 2.0 and 2.0 × their width, length of the other flagellomere 4.2 × their width (Fig. 12). Stigma 2.5 × longer than wide. Petiolate first metasomal segment exceptionally long and slender, 1.3 × longer than gaster. The color of male is darker than female. Head and petiolate first metasomal segment brown; ground color of metasoma black brown; legs and tegula yellowish-brown (Fig. 11).

Remarks. This new species can be distinguished from related species by its unique combination of open marginal cell and elongate last flagellomere in female. It is similar to W. decurta, but differs from it as follows: 1) first flagellomere 5.5 × longer than broad apically in female, further flagellomeres are not gradually shorter than first flagellomere, last two flagellomeres not thickened, last flagellomere elongate in female (first flagellomere 4.0 × longer than broad apically, further flagellomeres gradually shortening so that eleventh flagellomere 3.3 × longer than broad, twelfth flagellomere somewhat broader, last flagellomere clubbed broader and not elongate in W. decurta); 2) in dorsal view, head strongly rounded behind eyes, eyes 1.4× as long as temple (latter lees rounded, eye 1.8 × as long as temple); 3) OOL:OD:POL=11:3:6 (3:2:3); 4) clypeus 3.0 × as wide as high (clypeus twice as wide as high); 5) notauli shallow and wide (notauli deep and narrow) 6) fore wing 2-SR: 1-SR+M: m-cu=1:2:4 (1:1:2); 7) ovipositor sheath longer, in lateral view 1.9 × the length of third segment of hind tarsus (ovipositor sheath in lateral view as long as third segment of hind tarsus).

In the original description, W. decurta has the scutellar sulcus with five crenulae, but there is just one crenula in the photo (Papp 1995: Fig.16). This suggests there is an error in the text, so W. decurta has a scutellar sulcus with one crenula and is the same as this new species.

Host. Unknown.

Etymology. The name is derived from the Latin words “longius” (for “long”) which refers to elongate last flagellomere in female.

Distribution. China (Yunnan).