Miracorizus Yao, Cai & Ren

Yao, Yunzhi, Cai, Wanzhi & Ren, Dong, 2006, The first discovery of fossil rhopalids (Heteroptera: Coreoidea) from Middle Jurassic of Inner Mongolia, China, Zootaxa 1269, pp. 57-68 : 58-59

Genus Miracorizus Yao, Cai & Ren , gen. nov.

Type species. Miracorizus punctatus Yao, Cai & Ren , sp. nov.

Diagnosis: Body elongate, lateral sides subparallel, dorsal surface densely punctate. Head large, width and length subequal, over 0.5 times as long as pronotum, anteocular portion longer than postocular, apex surpassing first antennal segment; mandibular plates not surpassing clypeus; eyes relatively small, round; antenna 4­segmented, longer than head and pronotum combined, first segment shortest and thickest, second segment longest and slender, fourth segment fusiform, shorter and stouter than third segment; rostrum extending to mesocoxae, 4­segmented, first segment slightly thicker, second to fourth segments subequal in thickness, first elongate, third longest, fourth shorter than second, acuate distally. Pronotum trapezium, length shorter than width, with collar, posterior region with two longitudinal carinae; hind coxae widely separated, femora distinctly thicker than tibiae, fore and mid legs subequal in length, hind leg longer than mid leg, tarsus 3­segmented, subequal in thickness, first and second subequal in length, third longest; hemelytra macropterous, long and narrow, apical margin rounded, reaching to tip of abdomen, with distinctly embolium, corium elongated on costal margin, with deep medial fracture; clavus considerably longer than lateral side of scutellum, tapering, a veinlike carina and a vein arising at basal point, both crossing claval suture, carina reaching middle of corium, vein through posterior region of corium into membrane; membrane with some cells at middle and nearly 20 longitudinal veins distally. Abdomen oval, with narrow connexivum, ovipositor very long, not projecting beyond last paratergites.

Distribution: China.

Etymology: The generic name is a combination of the Latin mira (“special”) and Corizus (the type genus of this family).

Remarks: With numerous longitudinal veins in its membrane, the present fossil genus obviously belongs to Coreoidea, but it is difficult to assign it to family. The phylogeny and classification of Coreoidea bugs is based largely on such features as those of the structure of the metathoracic scent­gland, the bucculae, and the genitalia. These features are not well preserved or are invisible in fossil specimens. According to structures of the antenna and clavus and the ratio of head to pronotum, it is better to place the new genus in Rhopalidae . But it differs from extant Rhopalidae in fifth sutures of abdominal straight (vs. fifth segment of abdominal constricted in midline), a vein across claval suture (vs. without this vein). The phenomenon of a across the claval suture has been recorded in extant Enicocephalomorpha and Dipsocoromorpha and in fossil Coleorrhyncha ( Popov 1982; Zheng 1999). Obviously, it is an archicharacter.

Within all fossil taxa of Coreoidea, the new genus is closely related to Monstrocoreus Popov, 1968, but easily differs from the latter in the ratio of the antennal second segment to the third (about 1.5:1 [vs. 4.8: 4.4]) and clavus with a veinlike carina and a vein (vs. neither carina nor vein). Miracorizus is also similar to Weichangicoris Hong, 1984, but can be distinguished from the latter in the ratio of the second antennal segment to the third about 1.5: 1 (vs. 1.4:1.3), and the head distinctly shorter than the pronotum (vs. head and pronotum subequal in length).