Xenophilothis Kryzhanovskij, 1987

Lackner, Tomáš, 2010, Review of the Palaearctic genera of Saprininae (Coleoptera: Histeridae), Acta Entomologica Musei Nationalis Pragae (suppl.) 50, pp. 1-254 : 230-231

Xenophilothis Kryzhanovskij, 1987

Xenophilothis Kryzhanovskij, 1987: 25 . Type species: Philothis choumovitchi Thérond, 1965 in THÉROND & HOL- LANDE (1965), original designation.

Xenophilothis: OLEXA (1990) : 142; MAZUR (1997): 267, MAZUR (2004): 101.

Diagnosis. Cuticle not metallic; head comparatively small, narrow; eyes convex, visible from above, clypeus very large, semicircular; labrum larger than clypeus, expanding anteriorly; mentum widening anteriorly, anterior margin fringed with a dense row of long lamelliform setae; antennal scape thickened, with deep large punctures with long lamelliform setae; frontal stria vaguely impressed, frontal disc with confluent elongate prominent punctures. Pronotal sides strongly convergent anteriorly, anterior angles very acute and prominent, marginal pronotal stria complete; pronotal foveae absent; disc with irregular confluent punctures and wrinkles; pronotal hypomeron with long dense setae. Inner subhumeral stria complete, originating near elytral base, parallel to marginal elytral stria; dorsal elytral striae 3–5 strongly reduced basally; elytral epipleura setose; apical elytral stria obliterated; sutural elytral stria abbreviated on basal third. Pre-apical foveae absent, prosternal process compressed, punctate and setose, both sets of prosternal striae present, reduced. Protibia with two large triangular distal teeth topped by tiny rounded denticle, second tooth conspicuously larger than first, followed by a much shorter tooth topped by conspicuous denticle and followed by two microscopic denticles; all tarsal claws thin, straight, several times as long as apical-most tarsomere itself.

Differential diagnosis. Xenophilothis is doubtless the most curious and peculiar genus of the Palaearctic Saprininae , differing from the all known taxa by its peculiar shape of mentum (in all studied taxa it is rectangular, sub-rectangular or sub-trapezoid) that is widening ante- riorly, fringed with a dense row of long lamelliform setae, by the extraordinary labrum that is larger than clypeus (labrum is never larger than clypeus in all studied taxa) as well as by the almost complete inner subhumeral stria, originating from the elytral base and resembling a true dorsal elytral stria and by the basally strongly reduced dorsal elytral striae. Likewise, the shape of outer margin of protibia is very peculiar: second tooth is much larger than the first (usually teeth or denticles diminish in size in proximal direction). By the combination of these characters it cannot be confused with any currently known Palaearctic taxon.

Biology. Xenophilothis is a psammophilous genus, collected in pitfall traps in Saudi Arabia ( KRYZHANOVSKIJ 1987); it has also been collected at light ( KANAAR 2008).

Distribution. Xenophilothis contains a single species so far recorded from Algerian Sahara and deserts of Saudi Arabia, Oman and the United Arab Emirates ( MAZUR 1997, KANAAR 2008).

Discussion. This taxon is characterised by many autapomorphies: mentum widening anteriorly, anterior margin of mentum fringed with dense row of long lamelliform setae, large, semi-circular clypeus, labrum larger than clypeus and peculiarly shaped protibia with second tooth comparatively larger than first. Among possible plesiomorphic characters could be listed the complete inner subhumeral stria, non-dilated meso- and metatibiae, present protarsi. In the preliminary cladistic analysis of the Palaearctic genera of Saprininae (LACKNER, in prep.) this genus comes near the most-derived genera like Philothis or Ctenophilothis .

Species examined. Xenophilothis choumovitchi ( Thérond, 1965) .