Zopherobatrus Yin and Li

Yin, Zi-Wei & Li, Li-Zhen, 2015, Zopherobatrus gen. n. (Coleoptera: Staphylinidae: Pselaphinae), a new troglobitic batrisine from southwestern China, Zootaxa 3985 (2), pp. 291-295 : 292

Zopherobatrus Yin and Li , new genus

Type species: Zopherobatrus tianmingyii , new species (here designated)

Diagnosis. Head narrowed apically; median longitudinal carina on vertex faintly present; lacking frontal rostrum; with indistinct antennal tubercles. Pronotal disc moderately convex; median longitudinal sulcus usually present, with lateral longitudinal sulci; lacking antebasal spines; lacking spines on lateral margins. Elytra each with two basal foveae; lacking discal striae; disc strongly convex. Tergite IV (first visible tergite) longest, with indistinct marginal carina.

Description. Relatively large-sized, length more than 3 mm. Head nearly oval, narrowed apically; lacking frontal rostrum and frontal fovea; antennal tubercles low, area between them moderately depressed; vertexal foveae nude and small, located much below level of posterior margins of highly reduced eyes; elongate reverse U-shaped sulcus connecting vertexal foveae; vertex with short median longitudinal sulcus followed by short carina; with eleven elongate antennomeres, clubs indistinct; ocular-mandibular carinae present; eyes strongly reduced, indicated only by slightly raised cuticle; maxillary palpi with palpomeres II elongate, basally pedunculate, III oblong, IV nearly fusiform; gular depressed medially, two foveae in shared opening, gular carina only faintly indicated posterior to mouth parts.

Pronotum with median longitudinal sulcus often present; with lateral sulci and lateral antebasal foveae, foveae connected by transverse antebasal sulcus; lacking antebasal and lateral spines; indistinct inner- and outer pair of basolateral foveae present; paranotal carina indistinct; small lateral procoxal foveae present.

Elytra strongly narrowed at base, disc strongly convex; each elytron with two basal foveae, lacking discal striae; sutural striae complete; lacking subhumeral foveae and marginal striae. Metathoracic wings totally reduced.

Mesoventrite with forked lateral foveae, median foveae widely separated, opening in shared transverse cavity; lateral mesocoxal foveae present; setose lateral metaventral foveae present; metacoxae moderately separated; posterior margin of metaventrite with narrow median slit.

Abdominal tergite IV (first visible tergite) longest, mediobasal and basolateral foveae in interrupted basal sulcus, largely covered by posterior margin of elytra; lacking discal carinae, with single marginal carina; tergites V–VI short, subequal in length, VII as long as V and VI combined. Sternite IV (second visible sternite) longest, about twice length of V at midlength; V–VII subequal in length. Second and third tarsomeres subequal in length.

Males with tergite IV modified. Aedeagus with elongate median lobe; dorsal lobe flattened; with large, semisclerotized ventral membrane.

Comparative notes. The new genus is placed in the so-called Batrisocenus group of genera (sensu Nomura & Idris 2003) by the lack of pronotal lateral spines, presence of a transverse antebasal sulcus on the pronotum, each elytron with two basal foveae, and aedeagus with a moveable articulated dorsal lobe. Zopherobatrus is defined based on the lack of elytral discal striae, the strongly convex elytral disc, and a suit of morphological adaptations including the elongated body segments and appendages that are covered with long hairs, the strongly reduced eyes, the strongly narrowed elytral base, and complete loss of the metathoracic wings. In China, only two genera have species known to occur in caves, Tribasodellus and Tribasodites . Both genera belong to the Tribasodes genus group, and can be quickly separated from Zopherobatrus by the presence of the lateral (lack in a few Tribasodites species) and antebasal spines, each elytron with three basal foveae, presence of inner and outer marginal ridges on the abdominal tergite IV, and the aedeagus with an immovable dorsal plate. The male of Zopherobatrus has the anterolateral margins of the fourth maxillary palpomeres with several thickened setae, a character state that also occurs in many species of the genus Cratna Raffray , which also belongs to the Batrisocenus genus-group.

Etymology. The generic name is a combination of the Latin stem ‘ Zopher ’, meaning dark, and ‘ batrus ’, an arbitrary abbreviation of Batrisus Aubé. The gender is masculine.