Studies on palearctic Onthophagus associated with burrows of small mammals . IV . A new Iranian species belonging to the furciceps group ( Coleoptera , Scarabaeidae , Onthophagini )

Onthophagus (Palaeonthophagus) psychopompus sp. n. is described based on 75 specimens from Iran. Th e new species belongs to the furciceps species group, and has pholeophile habits, as the other species of the group. It appears to have a wide distribution in Iran, from 600 to 1950 m above sea level. A revised dichotomous key to the group is given.

Studies on palearctic Onthophagus associated with burrows of small mammals.IV.A new Iranian species belonging to the furciceps group (Coleoptera, Scarabaeidae, Onthophagini) Introduction At least since Falcoz (1914), it has been known that several species of Onthophagus Latreille, 1802, and other scarabaeoids, have a more or less exclusive association with rodents (pholeophily).Whereas burrow specialists are fairly well-known in the New World, they are still poorly investigated in the Palearctic.Rodents associated pholeobiont scarabs do not use dung deposited on open ground but exclusively droppings inside rodent burrows.Such dung beetle species are rarely collected outside burrows, and if so, usually under stones and most likely during their passage from one burrow to another.
During a research project undertaken by the authors on the scarabaeoid fauna of Iran associated with burrows of rodents, one of us (M.Moradi) has had the chance to collect some Onthophagus specimens belonging to an undescribed species.
In this paper, which is a continuation of the works by Ziani and Gudenzi (2006;2007;2009) on palearctic pholeophile Onthophagus, the new species is described.Methods and terminology follow Ziani and Gudenzi (2006).Etymology.Latinized from the classical Greek ψυχοπομπóς ("psyche", soul and "pompós", guide).In the mythology, psychopomps were fi gures who usually escorted the souls of the dead men to the netherworld.It is here referred to the subterranean habits of the new species.Th e noun is in apposition.
Black, dorsal side moderately shiny with a distinct isodiametric microreticulation, pubescence yellowish white, antennal scape, pedicel and funicle red, antennal club dark red.
Head (Fig. 2) short, clearly wider than long (width/length ratio = 1.73), clypeus round, weakly refl exed anteriorly, only very slightly emarginate at middle, anterior angles very broadly round, sides evenly arcuate with no sinuations, genae distinctly protruding from eyes; clypeo-frontal carina distinct, strongly bent backwards, its edge in contact with a very barely traced clypeo-genal suture; occipital carina extended in a high, slender, terminally expanding and bifurcate horn, very weakly dentate at middle apically, twice as long as width of its base; clypeal and frontal surface with rather coarse setigerous punctures, more spaced on frons than on clypeus, with long erected bristles clearly thicker basally, gradually thinner apically.
Pronotum (Fig. 1) convex, strongly declivous towards anterior edge, with four anterior, equidistant, slender and apically almost sharp tubercles, the middle two slightly more prominent and projected upwards, the two anterolateral slightly projected outwards; base margined; anterolateral angles round, subtruncate, dorsal surface with setigerous punctures, separated by half to one diameter anteriorly, gradually more spaced towards base, where punctures are separated by two to four diameters; each puncture bears a small granule at its anterior margin; bristles yellowish white, moderately long, scale-shaped, usually bifi d or trifi d at about two thirds of their length.
Elytral striae thin, shallow, slightly shining, their punctures only barely crenating interstriae; the latter fl at, granulose, granules minute, as big as strial punctures or a little smaller, each granule bearing at its base a long yellowish white bristle which is sometimes bifi d or trifi d, or lanceolate.
Pygidium with setigerous, large punctures, widely spaced, with long thin yellowish white hairs.
Fore tibial spur bent inwards and downwards.Fore, middle and hind femora ventrally with small, rather sparse setigerous punctures.
Head (Fig. 4) short, clearly wider than long (width/length ratio = 1.75), clypeus sub-truncate, clypeo-frontal carina distinct, slightly more elevate than in male, slightly bent backwards, frontal carina with a narrow lamina ending in a pair of erect horns, margin between horns straight or slightly sinuate in frontal view.
Pronotum (Fig. 3) with distinct, male-like, anterolateral tubercle on either side, and with an anteromedian transverse sunk gibbosity, only very slightly sinuate at middle.
Variability.Length 5.8 -9.9 mm, width 3.4 -5.7 mm.Occipital carina is femalelike in minor males.In some males, usually but not necessary minor specimens, pronotal anteromedian gibbosities are closer to each other than in most of the examined specimens.Some minor males, less than 6.0 mm long, have pronotal anteromedian tubercles joined together in a small projection, but always divided in two by a shallow depression.In one minor male (the smallest of the type series) anterolateral tubercles are only vestigial and the occipital carina is reduced to a straight transverse and very low ridge.On the other hand pronotal morphology is quite homogenous in both major or minor females.Only the occipital carina is clearly lower and straighter in minor than in major females.
Distribution.Th e new species appears to be widespread all over Iran (Fig. 8) from 620 to 1950 m above sea level.