Ctenophilothis Kryzhanovskij, 1987

Lackner, Tomáš, 2010, Review of the Palaearctic genera of Saprininae (Coleoptera: Histeridae), Acta Entomologica Musei Nationalis Pragae (suppl.) 50, pp. 1-254 : 90

Ctenophilothis Kryzhanovskij, 1987

Ctenophilothis Kryzhanovskij, 1987: 25 Ctenophilothis: OLEXA (1990) : 143; MAZUR (1997): 268; MAZUR (2004): 91.

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Type species: Xenonychus chobauti Théry, 1900 , original designation.

Diagnosis. Frontal stria completely absent, supraorbital stria present, frontal disc at times with weak median furrow; 8 th antennomere cupuliform, broader than pedicel, in several cases surrounding antennal club up to one-third of its length; club ventrally glabrous, dorsally with small patches of sparse sensilla; labrum without labral pits or setae, smooth; sub-apical tooth on left mandible extraordinarily small; sensory region of maxillary palpus curiously shaped, cap-like; lateral sides of pronotum fringed with very short setae; pronotal foveae absent; pronotal hypomeron with long amber setae. Elytral epipleuron setose; elytra obscurely variolate; elytral flanks smooth; elytral disc with two dorsal elytral striae 1–2, occasionally third stria also vaguely marked on apical third; inner subhumeral stria almost complete; propygidium and pygidium also obscurely variolate; pygidial flanks smooth. Prosternal apophysis forms a well-margined triangular disc; lateral prosternal striae absent; prosternal process densely setose, gradually sloping down anteriorly; antennal cavities absent; pre-apical foveae absent; discal marginal mesoventral stria anteriorly absent; meso-metaventral sutural stria somewhat elevated, carinate; mesoventral disc almost as long as broad; lateral metaventral stria shortened apically, curved outwardly; post-mesocoxal stria absent. Protibia curved, outer margin with numerous long movable denticles and two low teeth topped with stout denticle; apical margin ventrally with several short stout denticles; posterior surface smooth; protarsus absent; inner row of setae dense, setae lamelliform; meso- and metatibiae dilated; meso- and metatarsi telescope-like, their diameter markedly diminishing apically; each tarsomere with two strongly sclerotized lamelliform setae, one dorsally, one ventrally; claws of meso- and metatarsi thin, long and straight.

Differential diagnosis. Ctenophilothis is most similar to the species of the genus Philothis , but differing from them chiefly by the shape of protibia that is adorned with numerous long denticles in Ctenophilothis , whereas the species of the genus Philothis have their outer margin of protibia with two large triangular teeth topped with tiny denticle.

Biology. Ctenophilothis is a psammophilous genus with two described species. Its biology is poorly understood, Ctenophilothis chobauti has been collected in Algerian Sahara together with several other species of the genus Philothis ; biology of Ctenophilothis altus is virtually unknown.

Distribution. Sahara: Algeria, Egypt.

Species examined. Ctenophilothis altus ( Lewis, 1885) , C. chobauti ( Théry, 1900) .

Discussion. Ctenophilothis is most likely a monophyletic taxon, well characterised by several putative synapomorphies, among which can be listed the smooth, flattened labrum devoid of labral pits and setae, extraordinarily small sub-apical tooth of the left mandible, reduced dorsal elytral striae and the peculiarly shaped protibia with numerous long movable denticles on its upper margin. Most of these are present also with the presumably related taxon Philothis that lives basically in the same conditions as Ctenophilothis . On the other hand, setose ventral part of the body as well as strongly vaulted body and flattened eyes are probably morphological adaptations to the living conditions seen in other psammophilous genera.