Coframalaxius bletteryi gen. et sp. nov. from subterranean habitat in Southern France (Hemiptera, Fulgoromorpha, Cixiidae, Oecleini)

A new planthoppers genus and species of Cixiidae Oecleini, Coframalaxius bletteryi gen. et sp. nov. newly discovered in a cave near Nice in southern France, is described. Molecular analysis confirms the morphology-based classification of Coframalaxius as sister to Trigonocranus within the Oecleni. Several morphological characters are further discussed. A double-grasping coxo-femoral and femoro-tibial system is regarded as apomorphic for the oecline taxa and would allow the nymph to firmly grab the roots and rootlets on which it feeds or use to progress in the soil. Wing vein patterns are discussed in the Cixiidae: 1) for the forewings, Oecleini belong to the trifid type of the anterior MP branch, leading to the reinterpretation of some recently described Neotropical species, 2) for the hindwing, four connection types (U-, V-, Y- and I-types) between MP and CuA are described. Oecleini belongs to I-type with a complete fusion of MP3+4 with CuA1. Although the area where the cave is located is well-studied with respect to its regularly sampled epigean fauna for many years, the taxon is new to science, highlighting its probable completely hypogean life cycle and leading to consider Coframalaxius bletteryi as an eutroglophile species.