Unachionaspis MacGillivray 1921

Tian, Feng & Xing, Jichun, 2022, A new species of Unachionaspis MacGillivray, 1921 (Hemiptera: Coccomorpha Diaspididae) from China, Zootaxa 5124 (5), pp. 520-532 : 521-522

Genus Unachionaspis MacGillivray 1921

Unachionaspis MacGillivray 1921: 307 . Type species: Chionaspis colemani Kuwana 1902 (= Fiorinia signata Maskell 1897: 242 ).

Generic diagnosis. Appearance in life. Scale cover of adult female white, pear-shaped or pocket-shaped, dorsum slightly thickened, exuviae located at anterior end. Scale cover of immature male white, small and elongate, with slightly dilated sides, longitudinal ridges not obvious, exuviae located at anterior end.

Slide-mounted adult female. Body spindle-shaped, widest at or slightly posterior to the middle; metathorax and prepygidial segments each with ventral lateral margins slightly prominent; pygidium rounded or slightly triangular. Antennae each with 1 or 2 short setae; anterior spiracles each associated with trilocular disc pores, posterior spiracles with or without associated pores. Lobes numbering 2 or 3 pairs, each lobe elongate triangular. L 1 small, unilobulate, separate from each other; L 2 bilobulate, each lobule similar in shape to L 1; L 3 present or absent, and if so, unilobulate or bilobulate, similar in shape and size to L 2. Marginal gland spines on pygidium slender; without any gland spines between L 1. Number of marginal macroducts varying between species. Dorsal macroducts similar in size to marginal macroducts, present in submedian and submarginal groups on free abdominal segments; on pygidium, forming submedian and submarginal groups or scattered. Anal opening situated near base of pygidium. Perivulvar pores forming 5 groups.

Distribution. Algeria, China, Japan, Russia, South Korea, United States of America ( García Morales et al. 2016).

Remarks. Unachionaspis comprises a predominantly northeastern-Asiatic group of graminivorous species occurring mainly on bamboos. The genus is similar to Kuwanaspis MacGillivray 1921 and Nikkoaspis Kuwana 1928 in the characteristics of the pygidial lobes and the distribution of dorsal macroducts; however, unlike members of Unachionaspis , species of Kuwanaspis and Nikkoaspis possess pygidial plates on each side.