Reichardtiolus Kryzhanovskij, 1959

Lackner, Tomáš, 2010, Review of the Palaearctic genera of Saprininae (Coleoptera: Histeridae), Acta Entomologica Musei Nationalis Pragae (suppl.) 50, pp. 1-254 : 186-187

Reichardtiolus Kryzhanovskij, 1959

Reichardtiolus Kryzhanovskij, 1959: 217 (as a subgenus of Exaesiopus ). Type species: Saprinus duriculus Reitter, 1904 , original designation.

Reichardtiolus: KRYZHANOVSKIJ & REICHARDT (1976) : 112, 238; MAZUR (1984): 103; MAZUR (1997): 265; MAZUR (2004): 96.

Diagnosis. Cuticle dark brown, only with slight metallic tinge; clypeus and frontal disc rugulose-lacunose; frontal stria well impressed, occasionally weakened medially; pronotal hypomeron with short amber setae; pronotal disc coarsely and densely punctate; pronotal foveae absent; elytral surface entirely punctate; pre-apical foveae rather small; lateral disc of metaventrite, parts of metepisternum and lateral parts of abdominal sternites with short amber setae. Anterior margin of protibia formed by the anterior margin of the distal-most tooth; outer margin of protibia with two large teeth topped with large triangular denticle, followed by another low tooth topped by small triangular denticle; hind femur conspicuously thickened; metatibia triangularly dilated and thickened, outer margin with two widely separated sparse rows of short denticles of which the outer row only observable from ventral view (similar to Ammostyphrus or several species of Philothis ).

Diagnosis of this taxon is based solely on the species R. duriculus , since the other species, R. pavlovskii has not been examined and, based on its description, there is reason to believe that it belongs to a different genus.

Differential diagnosis. Most similar to the species of the genus Exaesiopus (originally described as a subgenus of Exaesiopus ), but differing from them by the absence of deep longitudinal rugae and otherwise rugulose-lacunose frontal disc, as well as the entirely punctate elytra (usually partly glabrous in Exaesiopus ). Protibia is also different between these two taxa: in Reichardtiolus its anterior margin is formed by the anterior margin of the distal-most tooth while in Exaesiopus it is normally formed. Reichardtiolus could be further confused with several species of the genus Paravolvulus or Hypocacculus . From Paravolvulus it differs by the thickened hind femora and thickened and dilated metatibia with two widely separated rows of short denticles, as well as the setose lateral disc of metaventrite, metepisternum and lateral parts of abdominal sternites. From the members of Hypocacculus this genus differs chiefly by the rugulose-lacunose frontal disc, thickened hind femora and metatibia (with widely separated two rows of short denticles) as well as by the setose pronotal hypomeron, lateral disc of metaventrite, parts of the metepisternum and lateral parts of abdominal sternites (usually glabrous in Hypocacculus ). Reichardtiolus can be also confused with Axelinus , with which it shares the rugulose-lacunose frontal disc and similar structure of protibia, but Axelinus is generally smaller and frontal stria is widely interrupted medially in this taxon (whereas it is in most cases complete, only slightly weakened medially in Reichardtiolus ). Furthermore, the hind femora are not particularly thickened with Axelinus and eyes are flattened, almost invisible dorsally, while they are well visible from dorsal view in Reichardtiolus .

Biology. Reichardtiolus is a psammophilous genus, occurring in the desert regions. Its biology is poorly documented.

Distribution. Reichardtiolus contains two described species: Reichardtiolus pavlovskii ( Kryzhanovskij, 1959) that is only known from two specimens found in Turkmenistan, and R. duriculus known from the following countries: Kazakhstan, Uzbekistan, Turkmenistan, Iran and West China ( MAZUR 1997). It is newly recorded from Jordan here.

Species examined. Reichardtiolus duriculus ( Reitter, 1904) .

Discussion. The monophyly of this taxon is questionable as it is supported by only few weak synapomorphies that are most likely homoplasies. Its relationship with the presumably related taxa (e.g. Hypocaccus , Exaesiopus , Paravolvulus or Ammostyphrus ) must be tested by further studies based on the modern phylogenetic methods.