Idiocysta China , 1930

Souma, Jun, 2020, Discoveries of the genera Baeochila and Idiocysta from Japan, with descriptions of two new species (Hemiptera: Heteroptera: Tingidae), Zootaxa 4731 (3), pp. 388-402 : 393-394

Genus Idiocysta China, 1930

Idiocysta China, 1930: 141 . Type species by original designation: Idiocysta hackeri China, 1930 .

Diagnosis. Recognized among other tingid genera by a combination of the following characters: body elliptical; head shorter than its maximum width across compound eyes, with or without spines; antennal segments I separated from each other at their bases; bucculae touching each other at anterior ends; pronotum convex in anterior part, tricarinate; pronotal disk irregularly covered with long pubescence among thoracic parts; hood roof-shaped, higher than pronotal disk at highest part; pronotal carinae laminate-shaped; paranota reflexed, expanding inward, bulged upward throughout their length, combining each other to form a semi-globose; outer margin of paranotum not resting on pronotal disk throughout its length; anterior margins of hemelytra not parallel to each other in rest; costal area distinct; subcostal area subvertical; discoidal area flat; delimiting veins strongly carinate; hypocostal lamina with a single row of areolae throughout its length; ostioles well-developed, teardrop-shaped, widened outward; metasternum wider than mesosternum; metasternal laminae curved outward; abdominal sternites VII–VIII in male and V–VII in female each with a transverse furrow throughout their width; pygophore elevated at center of venter; and ovipositor with well-developed ovivalvula at base.

Remarks. The genus Idiocysta comprises seven described species, namely, I. bicolor Drake & Poor, 1943 , I. dryadis Drake & Poor, 1943 , I. fijiana Drake & Poor, 1943 , I. floris Drake & Poor, 1943 , I. hackeri China, 1930 , I. vanuana Guilbert, 2001 , and I. vanuatuensis Guilbert, 1999 , all distributed in the South Pacific Islands, including part of the Australian region (cf. China 1930; Drake & Poor 1943; Drake & Ruhoff 1965a; Guilbert 1999, 2001).

In the early 20th century, Idiocysta was defined as having no cephalic spines based on the morphological characters of the type species, I. hackeri ( China 1930) . Four species with the same features, namely, I. bicolor , I. dryadis , I. floris , and I. vanuatuensis , were subsequently described ( Drake & Poor 1943; Guilbert 1999). On the other hand, two species having cephalic spines, namely, I. fijiana and I. vanuana , were described as members of Idiocysta without definite explanation ( Drake & Poor 1943; Guilbert 2001). However, I. fijiana and I. vanuana well match the original description of Idiocysta ( China 1930) except the cephalic structures. Therefore, the absence of cephalic spines is considered to be improper character in the definition of Idiocysta . Members of Idiocysta are provisionally divided into two species groups by the presence or absence of cephalic spines. The new species described below belongs to the group with cephalic spines.

This remarkable genus is easily distinguished from other tingine genera by the following characters: antennal segments separated from each other at their bases; pronotum convex tricarinate; pronotal disk irregularly covered with long pubescence among thoracic parts, pronotal carinae laminate-shaped, paranota reflexed, expanding inward, bulged upward throughout their length, combining each other in semi-globose form, outer margin of paranotum not resting on pronotal disk throughout its length; ostioles well-developed, teardrop-shaped, widened outward; metasternum wider than mesosternum; metasternal laminae curved outward.