Aglaostigma albicinctum (Takeuchi, 1953)

Fu, Yuanzun, Yuan, Yuan, Shen, Qian, Xu, Hao, Ye, Zheng, Guo, Li, Wu, Xiaoliang & Zhao, Yunhe, 2021, Taxonomic Notes and New Distribution and Host Plant Records for Sawflies and Woodwasps (Hymenoptera, Symphyta) of Japan VI, Bulletin of the National Museum of Nature and Science. Series A, Zoology 47 (4), pp. 163-188 : 166

Aglaostigma albicinctum (Takeuchi, 1953)

Japanese name: Urashimasou-habachi

( Fig. 2A–F )

Material examined. HONSHU: Tochigi Pref.:

1ˁ, Wami, 36°45′N 140°09′E, Nakagawa, coll. larva, on Arisaema serratum , 10. VI. 2014, mat. 13. VI., em. 6. IV. 2015, S. Ibuki; 1˂, same locality, coll. larva ( Fig. 2C ), on Actinidia polygama , 22. VI. 2016, mat. 26. VI., em. 26. IV. 2017, S. Ibuki; 1 ˂, same locality, coll. larva ( Fig. 2B, D, F ), on Impatiens textorii , 28. V. 2016, mat. 10. VI., em. 24. IV. 2017, S. Ibuki; 1 ˁ , same locality, coll. larva ( Fig. 2A ), on Symplocarpus renifolius , 31. V. 2018, mat. 13. VI., em. 21. IV. 2019, S. Ibuki .

Larva. Early or middle instar ( Fig. 2A–B ): head pale grayish brown ( Fig. 2A , probably earlier instar) or gray ( Fig. 2B , probably later instar); trunk and legs creamy white. Late instar ( Fig. 2C–E ): head blackish; trunk and legs creamy white, most of dorsal region brown with paired whitish lines dorsally, and supraspiracular, epi- pleural and hypopleural regions of each segment and two or three terminal segments blackish. Mature larva ( Fig. 2F ): entirely vivid pale green.

Host plants. Actinidiaceae : Actinidia polygama (Siebold et Zucc.) Planch. ex Maxim. (new record). Araceae : Arisaema spp. ( Okutani, 1967b), Symplocarpus renifolius Schott ex Tzvelev. (new record). Balsaminaceae : Impatiens textorii Miq. (new record).

Life history. This species has one generation a year. In lower mountains in central Honshu, the adults emerge in late April to May and the larval feeding stages are in May to June. The larva is solitary and has an extra molt on maturity before entering the soil.

Remarks. Okutani (1967b) recorded Arisaema spp. ( Araceae ) as hosts of Aglaostigma albicinctum and here we newly recognize three species of three different plant families as hosts of this sawfly based on rearing. This is a polyphagous species. See Okutani and Takeuchi (1953) and Okutani (1959) for a detailed description of the larva and life history.

Figures

Fig. 2. A–F, Aglaostigma albicinctum: A, early or middle instar larva on Symplocarpus renifolius, 31. V. 2018; B, early or middle instar larva on Impatiens textorii, 29. V. 2016; C, late instar larva on Actinidia polygama, 25. VI. 2016; D, late instar larva on I. textorii, 30. V. 2016; E, late instar larva on A. polygama, 1. VII. 2016; F, mature larva, 10. VI. 2016. G–J, Allantus meridionalis: G, early instar, 20. IX. 2015; H, J, middle or late instar larva, 12. X. 2015; I, mature larva, 13. X. 2015. K–M, Apethymus kunugi: K, probably late instar larva, 10. V. 2019; L, same larva, 12. V. 2019; M, same larva, matured, and cast skin above, 17. V. 2019. N–P, Corymbas nipponica: N, middle instar larva, 17. VI. 2016; O, same larva, late instar, 26. VI. 2016; P, same larva, matured, and cast skin above, 29. VI. 2016.All photographed by Ibuki.