Ismarus paradorsiger Chen, 2021

Zhang, Xiao, Chen, Hua-yan, Liu, Jing-xian & Luo, Shi-xiao, 2021, The genus Ismarus Haliday (Hymenoptera, Ismaridae) from China, Journal of Hymenoptera Research 82, pp. 139-160 : 139

Ismarus paradorsiger Chen sp. nov.

Figures 12 , 13 , 14

Diagnosis.

This species is most similar to the widely distributed I. dorsiger and I. kakamegensis in size and color patterns. It can be easily separated from I. dorsiger by the presence of a mesoscutal suprahumeral sulcus, and from I. kakamegensis by A1, which is distinctly longer than the length of A3 and A4.

Description.

Female. Body length 1.95-2.3 mm.

Colour. Body mostly pale yellowish, except mesoscutum, scutellum, metanotum, dorsal T1 and basal T2 variably dark brown; legs pale yellow, except hind tibia and basal tarsus somewhat brown; A1-A2 brown, remainder of antenna dark brown; wings hyaline or slightly infuscate medially, veins blackish brown.

Head. Head in dorsal view 2.0 × as wide as long; vertex abruptly sloping behind ocelli; POL as long as OOL; frons with ventrolateral areas densely setose, area below anterior ocellus with scattered setae; facial transverse carina slightly convex ventrally; A3 slightly shorter than A4; A4 1.2 × length of A5; A6-A14 with each segment approximately 2.0 × longer than wide; A15 approximately 3.0 × longer than wide.

Mesosoma. Dorsal pronotal area rugose-punctate and setose; lateral pronotal area rugose-punctate ventrally, smooth dorsally; mesoscutum smooth and bare, convex; mesoscutal suprahumeral sulcus present as six small pits; humeral sulcus deep and finely crenulate, slightly shorter than length of tegula; mesoscutellum smooth and slightly convex, posterior rim rounded; anterior mesoscutellar pit small, 0.25 × length of the mesoscutellar disc, distinctly crenulate at bottom, median keel strong; mesopleuron smooth and bare; metapleuron rugose and covered with dense whitish long setae.

Wings. Radial cell completely closed, moderately large, 3.6 × as long as wide and as long as marginal vein.

Legs. Fore and mid legs slender; hind tibia abruptly incrassate, its maximum width slightly wider than hind femur.

Metasoma. Petiole distinctly transverse, with irregular longitudinal costae dorsally; base of T2 with five short costae, median furrow short, 0.1 × length of T2, remainder of T2 smooth with scattered fine punctures; T3-T8 smooth with scattered fine punctures; suture between T2 and T3 obsolete but the following sutures between tergites distinctly impressed.

Male. Unknown.

Etymology.

The name refers to the high degree of similarity with I. dorsiger and is intended to be used as a noun in apposition.

Material examined.

Holotype, female: China: Guangdong, Maoming, Yunkaishan National Nature Reserve , LSX704, MT-GD33, 22°17'40.72"N, 111°12'37.97"E, 1480 m, 4-30.vii.2020, Long-long Chen, SCAU 3042199 (deposited in SYSBM) . Paratypes: (8 females) China : 1 female, Guangdong, Maoming, Yunkaishan National Nature Reserve , LSX591, MT-GD32, 22°16'38.37"N, 111°11'45.23"E, 30.iv-29.v.2020, Longlong Chen, SCAU 3049370 (SYSBM) ; 7 females, Yunnan, Yongshan County, Huanghua Town , 28.00°N, 103.51°E, 1500 m, 8.x.2010, Wei Dong, [misidentified as Ismarus dorsiger (Haliday)] Nos. 201000305, 201000308, 201000311, 201000312, 201000314, 201000316, 201000317 (SCAU) .

Distribution.

China (Guangdong, Yunnan).

Comments.

Liu et al. (2011) reported additional distribution records of Ismarus dorsiger (Haliday, 1831) from Yunnan Province of China. However, when we examined the 9 females identified as Ismarus dorsiger (Haliday, 1831) (deposited in SCAU), it turns out that these specimens have mesoscutal suprahumeral sulci, which are absent in I. dorsiger as was documented by Kolyada and Chemyreva (2016) and Kim et al. (2018a, b). Based on additional material collected from Guangdong, we describe them here as a new species. Therefore, I. dorsiger is still unknown from China.

Figures

Figure 12. Ismarus paradorsiger Chen, sp. nov., holotype, female (SCAU 3042199) A lateral habitus B head, anterior view, arrow indicates facial transverse carina convex ventrally C head and mesosoma, dorsal view D head and mesosoma, lateral view E propodeum and basal metasoma, dorsal view F apical metasoma, dorsal view, arrow indicates suture between T 2 and T 3 obsolete.

Figure 13. Ismarus paradorsiger Chen, sp. nov., holotype, female (SCAU 3042199) A wings B antenna C hind tibia.

Figure 14. Ismarus paradorsiger Chen, sp. nov., paratype, female (201000305) Lateral habitus.