Reichardtiolus duriculus (Reitter, 1904)

Lackner, Tomas, 2014, Revision of the genus Reichardtiolus Kryzhanovskij, 1959 (Coleoptera, Histeridae, Saprininae), ZooKeys 379, pp. 1-27 : 3-7

Reichardtiolus duriculus (Reitter, 1904) Figs 1, 2, 4, 6, 8, 10, 12, 14-23

Saprinus duriculus Reitter, 1904: 31.

Styphrus duriculus : Jakobson (1911): 651.

Hypocacculus duriculus : Bickhardt (1916): 97.

Exaesiopus duriculus : Reichardt (1926): 17; Reichardt (1941): 330, 333, Fig. 172.

Reichardtiolus duriculus : Kryzhanovskij and Reichardt (1976): 239, Figs 465, 466, 468; Mazur (1984): 103; Mazur (1997): 265; Mazur (2004): 96; Lackner (2010): 187, Figs 27, 67, 132, 593-610; Mazur (2011): 210.

Type locality.

Turkmenistan, Mary.

Type material examined.

Holotype: ♀, side-mounted on a triangular point, four segments of meso-tarsomere broken off, last two meta-tarsomeres broken off, with the following labels: “♀” [printed]; followed by: “Merw” [printed]; followed by: “Ahnger” [printed]; followed by: " Styphrus duriculus / m. 1904 Typ" [written label]; followed by: "coll. Reitter" [printed]; followed by: "1960 / Exaesiopus / ( Reichardtiolus ) / duriculus Rchdt (sic!) / Kryzhanovskij det." [printed-written]; followed by: "Holotypus 1904 / Saprinus / duriculus / Reitter" [red-framed printed-written label] (HNHM).

Additional material examined.

Turkmenistan: 1 ♂, Anau, Karakum, 21.iv.1981, A. Olexa lgt.; 1 ♀ & 1 spec., Repetek, 12.iv.1989, M. Nikodým lgt.; 1 ♀, Amurdarja-Kirki, 1.-5.v.1993, no collector (all exs. TLAN); 1 spec., Karakum, Repetek, 4.v.1983, Krivoshatsky lgt., at light; 1 spec., Tschardshou, Repetek, 14.iv.1983, Snížek lgt. (both CPV); 4 specs., ibid, but MSNG; 1 spec., Repetek, in burrow of Rhombomys opimus , 1.iv.1980, Krivoshatskij lgt. (ZIN); 1 spec., ibid, but 19.iv.1982, at light, same collector (ZIN); 1 spec., 20 km E of Kerka, 23.iv.1984, at light, T. Vereschagina lgt. (ZIN). KAZAKHSTAN: 1 ♀, Temir env., river Chatryly, 26.v.1908, D. Borodin & B. Uvarov lgt. (ZIN); 2 specs., Mangyshlak peninsula, Schtepe env., 24.-27.iv.1999, Smirnov leg (CAS); 1 spec., without further data (MSNG); 1 spec., low Ili River, env. Bakanas, 15.iv.1971, Badenko lgt. (ZIN); 1 spec., Gurivskaya oblast, Makata distr., prom. Iskair, 13.vi.1981, Saraev lgt. (ZIN). UZBEKISTAN: 1 ♀, Syr-Darya gebiet, Perovsk uezd, 5.v.1905, J. Baeckmann lgt. (ZIN); 1 ♀, Kyzyl-Kum, Yny-Darja, Perovsk uezd, 24.iv.1911, Ivanov lgt. (ZIN); 2 specs., Kyzyl-Kum, Ayak-Agytma, 20.iv.1965, G. Medvedev lgt., sands (ZIN); 1 spec., Kyzyl-Kum, 70 km S of Tamdy, 1.v.1965, L. Arnoldi lgt. (ZIN). Tajikistan: 1 ♀, Syr-Daria Riv., nr. Karakum Reservoir, at 40°32'16''N, 70°17'47''E, 13.iv.61, sandy desert, I.K.Lopatin lgt. (CAT). CHINA: 1 ♀, Xinjiang Prov., mountain range Tokuz-Daban, upper Cherchen [=Qarqan] River, v. [18]90, Pevtzov lgt. (with doubt) (ZIN).

Re-description.

Although this species has been recently re-described by the author ( Lackner 2010: 187), and the reader is referred there for the exhaustive account of SEM micrographs and drawings of the mouthparts and sensory structures of the antenna, I prefer to repeat its re-description here for the reason that the following three species ( Reichardtiolus sphingis , Reichardtiolus aldhaferi and Reichardtiolus perses ) are morphologically very similar to Reichardtiolus duriculus . Those species are consequently provided only with diagnostic descriptions illuminating their respective differences from Reichardtiolus duriculus .

Body length: PEL: 2.00-3.40 mm; APW: 0.65-1.05 mm; PPW: 1.375-2.40 mm; EL: 1.25-2.25 mm; EW: 1.50-2.70 mm. Body (Fig. 1) elongate oval, strongly convex, cuticle dark brown with feeble metallic luster; legs, antennae and mouthparts rufous. Antennal scape (for fig. see Lackner 2010, fig. 596) slightly thickened, with several short setae; club (for fig. see Lackner 2010, fig. 595) rather large, without visible articulation, apical four-fifths covered with short sensilla intermingled with longer sparse erect sensilla, basal fifth glabrous; sensory structures of antennal club (for fig. see Lackner 2010, fig. 27) in form of stipe-shaped vesicle situated under circular sensory area on internal distal margin of the ventral side of antennal club.

Mouthparts: mandibles (for fig. see Lackner 2010, fig. 101) with rounded outer margin, strongly curved inwardly, mandibular apex acutely pointed; sub-apical tooth on inner margin of left mandible blunt; labrum (for fig. see Lackner 2010, fig. 67) convex, coarsely punctate; with two labral pits, each with two well-sclerotized setae; terminal labial palpomere thickened, its width about half its length; mentum (Fig. 4) sub-trapezoidal, anterior margin shallowly emarginate medially; antero-lateral corners with few short setae, lateral margins with a single row of short ramose setae; disc of mentum imbricate, asetose; cardo of maxilla with few short setae on lateral margin; stipes triangular, with three short setae; terminal maxillary palpomere thickened, its width about half its length, about twice as long as penultimate.

Clypeus (Fig. 2) slightly concave medially, rounded laterally, rugulose-lacunose; frontal stria well impressed, carinate, almost straight, somewhat weakened medially, continued as well-impressed, carinate supraorbital stria; frontal disc (Fig. 2) densely punctate; eyes slightly convex, visible from above.

Pronotum (Fig. 1) convex, pronotal sides rounded, convergent anteriorly on their apical third, apical angles inconspicuous; marginal pronotal stria complete, carinate; disc with very deep, dense and coarse punctures, laterally rugulose-lacunose, medially punctuation weakens and becomes sparser; pronotal hypomeron with sparse short amber setae.

Elytral epipleuron with a row of deep punctures; marginal epipleural stria well impressed, complete; marginal elytral stria complete, deeply impressed, carinate, continued as complete apical elytra stria. Humeral elytral stria weakly impressed on basal third, often doubled; inner subhumeral stria inconspicuous, present as tiny median fragment; elytra with four dorsal striae 1-4, in large punctures, first, second and third dorsal striae about the same length, reaching approximately elytral half apically, fourth dorsal elytral stria weakly impressed on basal third (occasionally longer apically), connected to complete sutural elytral stria. Elytral disc with deep round punctuation, punctures separated by 2-4 times their diameter, becoming finer apically and laterally; between sutural elytral stria and elytral suture a row of regular fine punctures present.

Propygidium transverse, coarsely and densely punctate; pygidium (Fig. 12) almost as long as broad, with sparser punctuation; interspaces in both cases finely imbricate.

Anterior margin of median portion of prosternum (Fig. 10) rounded; marginal prosternal stria present laterally and as vague anterior fragment; prosternal foveae rather small; prosternal process rather narrow, slightly concave; carinal prosternal striae slightly carinate, almost parallel, united in front of strongly carinate, shortened lateral prosternal striae. Surface between carinal prosternal striae almost smooth, prosternal apophysis with several microscopic setae; lateral parts of prosternal process strigulate with scattered microscopic punctures fringed with tiny setae.

Anterior margin of mesoventrite (Fig. 6) feebly emarginate medially; discal marginal mesoventral stria well-impressed, carinate, slightly weakened anteriorly; disc of mesoventrite with scattered deep, round punctures, fringed with microscopic setae; meso-metaventral sutural stria absent; meso-metaventral suture distinct.

Intercoxal disc of metaventrite slightly longitudinally concave in male, with coarse scattered punctures, area around lateral metaventral stria smooth; lateral metaventral stria (Fig. 8) deeply impressed, carinate, extending obliquely and shortened apically; lateral disc of metaventrite (Fig. 8) with shallow large setiferous punctures; metepisternum on basal half with similar punctuation, apical half of metepisternum (Fig. 8) almost smooth, fused metepimeron with few punctures; metepisternal stria present along entire fused metepimeron and metepisternum, intermittent basally.

Intercoxal disc of first abdominal sternite completely striate laterally, with sparse coarse punctuation.

Protibia (for fig. see Lackner 2010, fig. 603) flattened and somewhat dilated, apical protibial margin formed by anterior margin of large sub-triangular distal-most tooth topped with large triangular denticle, outer margin apart from this tooth with another similar tooth topped with large triangular denticle, followed by another, much lower tooth topped by much smaller triangular denticle and another microscopic denticle entombed in outer margin of protibia; setae of outer row on anterior surface of protibia sparse, regular and short; setae of intermediate row similarly sparse and regular, much shorter than those of outer row; protarsal groove moderately deep; anterior protibial stria present only on basal third; tarsal denticles absent; protibial spur tiny, bent, growing out from apical protibial margin; apical margin of protibia posteriorly without denticles; outer part of posterior surface of protibia sparsely punctate, distinctly separated from glabrous median part of posterior surface by irregular costiform stria fringed with sparse microscopic setae; posterior protibial stria complete, deeply impressed, with sparse microscopic setae; inner-ventral denticles absent; inner margin with single row of well sclerotized setae.

Mesotibia (for fig. see Lackner 2010, fig. 601) slightly thickened, outer margin with two sparse rows of thin denticles greater in size apically; setae of outer row rather dense, strongly sclerotized and longer than denticles of outer margin; setae of intermediate row sparse, microscopic; posterior mesotibial stria inconspicuous; anterior surface of mesotibia imbricate, with scattered minuscule punctures with microscopic setae; anterior mesotibial stria shortened apically, almost complete; mesotibial spur stout, rather short; apical margin with several tiny denticles; claws of apical tarsomere longer than half its length; metatibia basically similar to mesotibia, but much more thickened and dilated, rows of denticles of outer margin widely separated, outer row of denticles (for fig. see Lackner 2010, fig. 602) observable only from ventral view.

Male genitalia: Eighth sternite (Figs 14-15) divided medially, apically with short setae and a setose velum, 8th tergite apically only faintly emarginate, 8th sternite and tergite fused laterally, deep from lateral view (Fig. 16). Tenth tergite (Fig. 17) basally almost straight; 9th tergite apically inwardly arcuate, anterior angles prominent (Fig. 17), sclerotization not divided medially. Spiculum gastrale (Figs 19-20): tips on anterior end without strong sclerotization, posterior end outwardly arcuate. Basal piece of aedeagus (Figs 22-23) rather short, ratio to tegmen 1:5; aedeagus tube-like, with large opening for median lobe, apically with numerous pseudopores, curved laterally (Fig. 22); apex of aedeagus blunt (Fig. 21).

Differential diagnosis.

Reichardtiolus duriculus is most readily separated from Reichardtiolus pavlovskii from which it differs by the body size and other substantial morphological characters, e.g. the presence (vs. absence) of prosternal foveae, presence of elytral striae (almost indiscernible in Reichardtiolus pavlovskii ) etc. The differences among Reichardtiolus duriculus and other three congeners are subtler and the species are best separated by their male terminalia; the reader is referred to the key to species for details.

Biology.

A psammophilous species, usually collected in sand, occasionally collected also in rodent’s burrows or even at light.

Distribution.

Turkmenistan, Kazakhstan, Uzbekistan, western China (?). Newly recorded from Tajikistan (Fig. 72).

Remarks.

The single specimen from Xinjiang is a female, and differs from the specimens from ex-Soviet middle Asia especially by very coarsely and rugosely punctate frons and clypeus, as well as denser and coarser punctuation of mesoventrite and pygidium. However, I am hesitant to describe a new species based on a single female and prefer rather keeping it tentatively as a specimen of Reichardtiolus duriculus . Certainly, acquisition of new material containing male specimens from the above-mentioned locality would help clarify its taxonomic status.