Afronurus obliquistriatus ( You, Wu, Gui & Hsu, 1981 )

Zhang, Wei, Lei, Zhi-Ming, Li, Wen-Juan & Zhou, Chang-Fa, 2021, A contribution to the genus Afronurus Lestage, 1924 in China (Ephemeroptera: Heptageniidae, Ecdyonurinae), European Journal of Taxonomy 767 (1), pp. 94-116 : 109-110

Afronurus obliquistriatus ( You, Wu, Gui & Hsu, 1981)

Figs 6D , 7G–I , 12C , 13E–F

Cinygmina obliquistriata You, Wu, Gui & Hsu, 1981: 26 , pl. 1 figs 1–13 (male, female). Types: male, female, from Jiangsu, China.

Cinygmina obliquistriata – Gui 1985: 86. — Wu et al. 1986: 65, figs 12–22 (nymph). — Zhang & Cai 1991: 237. — You & Gui 1995: 51, fig. 50 (male). — Zhou & Zheng 2003: 756, figs 9, 12, 16 (male and nymph).

Afronurus obliquistriatus – Braasch & Jacobus 2011: 65.

Material examined

Holotype CHINA • ♂; Jiangsu Province, Yi-Xing city, Ming-Ling village ; 31°10′5.02″ N, 119°40′17.52″ E; alt. 67 m; 11 Aug. 1980; J. Zhang and S.S. She leg.; NNU.

Paratypes CHINA • 13 ♂♂; same collection data as for holotype; NNU .

Additional material

CHINA • 15 ♂♂, 18 ♀♀ (some reared from mature nymphs), 20 nymphs; Zhejiang Province, Lin-An city, unnamed creek in front of Tian-Mu Hotel; 30°19′16.7″ N, 119°26′55.7″ E; alt. 479 m; 3–6 Apr. 2019; W. Zhang and Z.X. Ma leg.; NNU .

Description

Nymph

See Zhou & Zheng (2003: 757, fig. 9, first description).

Male imago

See You et al. (1981: 26, figs 1–13, original description).

Egg ( Fig. 6D )

Ovoid, small KCTs concentrated at each pole, chorion decorated with small KCTs, large KCTs and oval micropyle located equatorially.

Remarks

In China, the nymphs of A. obliquistriatus and A. rubromaculatus are the most difficult to distinguish, especially when they are young or typical stripes are faded. Herein, the following combination of characters are differentiable: 1) lingua is much shorter than superlinguae in A. obliquistriatus (as in Fig. 10B ), while that in A. rubromaculatus is subequal in length (as in Fig. 2C ); 2) number of comb-shaped setae on maxillae: 11–13 in A. obliquistriatus and 14–16 in A. rubromaculatus ; 3) A. obliquistriatus has lateral oblique stripes on terga I–X ( Fig. 7H ) and A. rubromaculatus has pale dots on terga I–X only ( Fig. 7K ); 4) posterolateral projections of A. obliquistriatus are moderately developed on segments III–VIII ( Fig. 7H ) but weakly developed in A. rubromaculatus (as in Fig. 7E ); 5) caudal filaments of A. obliquistriatus have brown stripes on every two or three articulations ( Fig. 7I ), but A. rubromaculatus has dark brown stripes on some articulations ( Fig. 7L ).

In male imago, the color pattern of abdominal terga and shape of genitalia can be used as valid characters to distinguish them: 1) A. obliquistriatus has unique oblique stripes on abdomen ( Fig. 12C ), while A. rubromaculatus has reddish longitudinal stripes laterally ( Fig. 12D ); 2) penial lobes of A. obliquistriatus are slightly divergent ( Fig. 13E–F ), whereas A. rubromaculatus has a distinct conelike projection between obviously divergent penial lobes ( Fig. 13G–H ).

Distribution

China (Shaanxi, Henan, Hubei, Hunan, Anhui, Guizhou, Jiangsu, Zhejiang, Guangxi, Fujian, Guangdong, Hainan).

Figures

Fig. 6. SEM photos of eggs. A. Afronurus drepanophyllus sp. nov. (NNU). B. A. furcatus (Zhou & Zheng, 2003) (NNU). C. A. hunanensis (Zhang & Cai, 1991) (NNU). D. A. obliquistriatus (You et al., 1981) (NNU). E. A. rubromaculatus (You et al., 1981) (NNU). F. A. yixingensis (Wu & You, 1986) (NNU).

Fig. 7. Nymphal habitus of five species of Afronurus Lestage, 1924. A–C. A. furcatus (Zhou & Zheng, 2003) (NNU). D–F. A. hunanensis (Zhang & Cai, 1991) (NNU). G–I. A. obliquistriatus (You et al., 1981) (NNU). J–L. A. rubromaculatus (You et al., 1981) (NNU). M–O. A. yixingensis (Wu & You, 1986) (NNU). A, D, G, J, M. Head capsule. B, E, H, K, N. Abdominal terga. C, F, I, L, O. Caudal filaments. Scale bars: A–B, D–E, G–H, J–K, M–N = 2.0 mm; C, F, I, L, O = 1.0 mm.

Fig. 12. Male abdominal terga of five species of Afronurus Lestage, 1924. A. A. furcatus (Zhou & Zheng, 2003) (NNU). B. A. hunanensis (Zhang & Cai, 1991) (NNU). C. A. obliquistriatus (You et al., 1981) (NNU). D. A. rubromaculatus (You et al., 1981) (NNU). E. A. yixingensis (Wu & You, 1986) (NNU). Scale bars = 1.0 mm.

Fig. 13. Genitalia of five species of Afronurus Lestage, 1924. A–B. A. furcatus (Zhou & Zheng, 2003) (NNU). C–D. A. hunanensis (Zhang & Cai, 1991) (NNU). E–F. A. obliquistriatus (You et al., 1981) (NNU). G–H. A. rubromaculatus (You et al., 1981) (NNU). I–J. A. yixingensis (Wu & You, 1986) (NNU). A, C, E, G, I. Genitalia. B, D, F, H, J. Penes enlarged; arrows show titillators. Scale bars: A, C, E, G, I = 0.5 mm; B, D, F, H, J = 0.2 mm.

Fig. 10. Mouthparts of Afronurus hunanensis (Zhang & Cai, 1991) (NNU). A. Labrum (ventral view). B. Hypopharynx (ventral view). C. Left mandible (ventral view). D. Right mandible (ventral view). E. Labium. F. Maxillae. G. Incisors of left mandible. H. Incisors of right mandible. Scale bars: A–D, F = 0.5 mm; E = 1.0 mm; G–H = 0.1 mm.

Fig. 2. Mouthparts of Afronurus drepanophyllus sp. nov. (NNU). A. Labrum (ventral view). B. Median bristles of ventral labrum. C. Hypopharynx (ventral view). D. Left mandible (ventral view). E. Right mandible (ventral view). F. Labium. G. Maxillae. H. Incisors of left mandible. I. Incisors of right mandible. Scale bars: A, C–G = 0.5 mm; B = 0.3 mm; H–I = 0.2 mm.