Ishiharanus Hori, 1969

Constant, Jérôme & Pham, Hong Thai, 2025, Issid planthoppers from Bach Ma and Phong Dien in Central Vietnam: (II) Tribe Hemisphaeriini (Hemiptera: Fulgoromorpha: Issidae), European Journal of Taxonomy 994 (1), pp. 1-76 : 40-41

Genus Ishiharanus Hori, 1969

Ishiharanus Hori 1969: 58 .

Type species: Gergithus iguchii Matsumura, 1916 by original designation.

Ishiharanus – Che et al. 2007: 611 (proposed as junior synonym of Gergithus Stål, 1870 – erroneous!). — Chen et al. 2014: 49 (treated as a junior synonym of Gergithus Stål, 1870 – erroneous!). — Gnezdilov 2018: 1342 (reinstated as a valid genus, diagnosis, composition, distribution, compared to Bruneastrum Gnezdilov, 2015 and Neohemisphaerius Chen, Zhang & Chang, 2014 ). — Cho et al. 2024: 983 (notes on previous taxonomic changes).

Note: Meng et al. (2017) erected the new genus Gnezdilovius Meng, Webb & Wang, 2017 (type species: Gergithus lineatus Kato, 1933 ) to include a number of species previously placed in Gergithus Stål, 1870 . However, they included Gergithus iguchii Matsumura, 1916 , the type species of Ishiharanus , in Gnedilovius, and hence implicitely treated the two genera as synonyms, without considering the priority of Ishiharanus or even mentioning the genus in their work. This issue was resolved by Gnezdilov (2018) by reinstating Ishiharanus as a monotypical genus containing only I. iguchii ( Matsumura, 1916) , distributed from Japan to eastern and southeastern China, and south to Central Vietnam.

Diagnosis

The genus is defined by the following distinctive set of characters (modified from Gnezdilov 2018):

(1) the smooth frons narrow between the eyes, wider above clypeus (twice as wide) and about 1.1–1.3 times as long as wide;

(2) the clypeus without carina;

(3) the vertex transverse, about 1.7–1.9 times as wide as long in midline;

(4) the tegmina without a “shoulder-like” projection in dorsal view and without a projection under the eye in lateral view;

(5) the hind wings well developed, nearly as long as tegmina;

(6) the asymmetrical aedeagus, upcurved and twisted, with a pair of apical pointed processes and a pair of lateroventral processes in the basal portion;

(7) the capitulum of the gonostyli with a long, wide neck;

(8) the posterior margin of the pygofer convex, without a spine;

(9) the anal tube widening from base to apex, with the posterior margin more or less distinctly trilobed (“with median spout-like process” according to Gnezdilov 2018).

Remarks

Gnezdilov (2018) stated that the periandrium in Ishiharanus is symmetrical, while the illustrations in Hori (1969: fig. 2, 2) and Chen et al. (2014: fig 2-16, k–l) show an asymmetrical, twisted aedeagus, confirmed by our observations of specimens of the type species I. iguchii ( Matsumura, 1916) and of the other species treated hereunder.

Species included

Ishiharanus dinhanus sp. nov.

I. iguchii ( Matsumura, 1916)

I. pulchellus sp. nov.