Exaesiopus henoni (Schmidt, 1896)

Lackner, Tomas, 2015, Revision of the genus Exaesiopus Reichardt, 1926 (Coleoptera, Histeridae, Saprininae), ZooKeys 479, pp. 65-108 : 76-81

Taxon classification Animalia Coleoptera Histeridae

Exaesiopus henoni (Schmidt, 1896) Figs 35, 36-43, 44-45, 46-54

Pachylopus henoni Schmidt 1896: 206

Saprinus henoni : Bickhardt 1910: 106.

Exaesiopus henoni : Mazur (1984): 101; (1997): 264; (2004): 92; (2011): 210.

Type locality.

Aïn Sefra, Algeria.

Type material examined.

Lectotype, ♀, side-mounted on triangular point, left metatarsus missing, with the following labels: “♀” (printed); followed by: " henoni m / Aïn Sefra" (written); followed by: "coll Schmidt- / Bickhardt" (printed); followed by: " Pachylopus / henoni Schmidt / Coll. Schmidt-Bickhardt" (printed); followed by: "LECTOTYPE / N. Dégallier” (red label, printed) (ZMHUB). 1 ♂ paralectotype, with the following labels: “Aïn Sefra / Hénon” (printed); followed by: " Pachylopus / Henoni / Schm. Type" (written); followed by: "PARA- / LECTOTYPE / N. Dégallier” (printed) (BMNH). 1 ♀, paralectotype, with the following labels: “Aïn Sefra / Hénon” (printed); followed by: " Pachylopus / Henoni / Cotype '96 Sch." (written); followed by: "PARA- / LECTOTYPE / N. Dégallier” (printed) (BMNH); Paralectotypes: 1 ♂ & 4 specs., with the following labels: “Aïn-Sefra / Hénon” (printed); followed by: "Museum Paris / ex coll. / P. de Peyerimhoff" (printed); followed by: "PARA - / LECTOTYPE / N. Dégallier” (red label, printed) (MNHN).

1 Syntype, ♀, side-mounted on a triangular point, with the following labels: “♀” (printed); followed by: “Type” (brick-red label, printed); followed by: “Aïn-Sefra / Hénon” (printed); followed by: " Pachylopus / Henoni typ" (written); followed by: " Pachylopus / henoni Schmidt / Coll. Schmidt-Bickhardt" (printed); 1 Syntype, ♀, side-mounted on a triangular point, with the following labels: “♀” (printed); followed by: “Type” (brick-red label, printed); followed by: “Aïn-Sefra / Hénon” (printed); followed by: " Pachylopus / Henoni m" (written); followed by: "coll. J. Schmidt" (printed); followed by: " Pachylopus / henoni Schmidt / Coll. Schmidt-Bickhardt" (printed); 1 Syntype, ♀, side-mounted on a triangular point, with the following labels: “♀” (printed); followed by: “Type” (brick-red label, printed); followed by: “Aïn-Sefra / Hénon” (printed); followed by: " Pachylopus / Henoni m" (written); followed by: " Pachylopus / henoni Schmidt / Coll. Schmidt-Bickhardt" (printed) (all syntypes ZMHUB).

Additional material examined.

ALGERIA: 1 spec., Mraier, D. de Constantine, coll. de Vauloger (ZIN); 4 ♂♂ + 1 ♀ + 3 specs., Aïn Sefra, Hénon (MNHN); 1 spec., idem, but, v-vi.1896, L. Bleuse leg. (MNHN); 1 ♂ + ♀, idem, but CYG; 3 specs., Colomb-Béchar, 27.iv.1923, J. Thérond leg. (MNHN); 1 spec., ibid, but 30.iv.1923 (MNHN); 2 specs., Mraier, D. de Constantine, Vauloger (MNHN); 1 spec., Biskra, Dr. H.J. Veth leg. (NCB); 3 specs., Aïn Sefra, 26.iv.1987, A. Olexa (TLAN); 1 ♀, ibid, but 25.-27.iv.1987, D. Král leg. Djibouti: 1 ♀, As-Eyla, viii.1976 (NCB). Libya: 1 spec., Tripolitania, Wadi Sofeggin, 21.-23.v.1963, no collector (MNHN).

Diagnostic description.

Body length: PEL: 2.50-2.75 mm; APW: 0.875-1.00 mm; PPW: 1.875-2.00 mm; EW: 2.125-2.20 mm; EL: 1.625-1.80 mm. Body (Fig. 35) similar to Exaesiopus grossipes , but without any trace of metallic tinge; antennae similar to those of Exaesiopus grossipes ; sensory structures of the antennal club not examined. Mouthparts generally similar to those of Exaesiopus grossipes ; mentum (Fig. 36) sub-quadrate, feebly inwardly arcuate on anterior margin; anterior margin with several long setae, lateral margins with single row of sparse shorter ramose setae; stipes of maxilla with four setae (three in Exaesiopus grossipes ); rest of the mouthparts as in Exaesiopus grossipes . Clypeus (Fig. 37) as in Exaesiopus grossipes , almost smooth; frontal and supraorbital striae as in Exaesiopus grossipes ; postorbital stria missing (present in Exaesiopus grossipes ); frons with two deep chevrons.

Pronotal disc (Fig. 35) with ellipsoid to round, rather sparse punctation, punctures separated by their own to several times their diameters, postero-median part of disc always smooth, punctation stopping short of lateral pronotal margin leaving a narrow impunctate band; rest of the pronotum as in Exaesiopus grossipes . Elytra generally as in Exaesiopus grossipes ; inner subhumeral stria shortly present medially; dorsal elytral striae for short distance surpassing elytral half; elytral punctation variable, in most specimens present only on fourth elytral interval, but can also at times be present on other elytral intervals (a specimen from Libya), or almost completely missing (a specimen from Algeria); along elytral suture can reach almost elytral base, punctures irregular, variously deep, separated often by several times their own diameter, elytral flanks and humeri always smooth. Propygidium (Fig. 38) and pygidium similar to those of Exaesiopus grossipes ; punctation somewhat sparser (compare Figs 5 and 38). Prosternum (Fig. 39) generally similar to that of Exaesiopus grossipes , but prosternal foveae very weakly impressed, often indiscernible (absent?); prosternal process deeply concave, constricted, prosternal structures and configuration of the two sets of prosternal striae similar to those of Exaesiopus grossipes . Disc of mesoventrite (Fig. 40) almost smooth, similar to that of Exaesiopus grossipes , but almost as long as wide; meso-metaventral sutural stria undulate; intercoxal disc of metaventrite with longitudinal depression in both sexes, more prominent in male, smooth, basally with several irregular rows of sparse punctures; lateral metaventral stria (Fig. 41) obliquely arcuate, apically almost reaching metacoxa; lateral disc of metaventrite (Fig. 41) and metepisternum generally similar to those of Exaesiopus grossipes , but metepisternum with denser and coarser punctation and longer setae; meterpisternal stria unrecognizable beneath setae (absent?). Intercoxal disc of first abdominal sternite as in Exaesiopus grossipes . Protibia (Figs 42-43) on outer margin with a single massive triangular tooth, followed by another lower tooth; both teeth topped by triangular denticle followed by two-three inconspicuous rounded denticles entombed in outer protibial margin; protibial spur inconspicuous (absent?); outer part of posterior surface of protibia (Fig. 43) smooth, separated from comparatively narrower median part by a definite ridge, posterior protibial stria complete, terminating in two minuscule inner posterior denticles; inner margin of protibia with double row of long dense lamellate setae. Mesotibia (Fig. 44) as in Exaesiopus grossipes , but denticles on outer margin longer. Metatibia (Fig. 45) even more triangularly dilated and thickened than that of Exaesiopus grossipes ; outer margin with about four strong denticles larger in size apically; dilated anterior margin dorsally with several irregular rows of scattered tiny rounded denticles.

Male genitalia. Eighth sternite (Figs 46-47) apically with a brush of sparse setae and a moderately sized velum; eighth tergite apically faintly inwardly arcuate; eighth sternite and tergite fused laterally (Fig. 48). Ninth tergite (Fig. 49) apically faintly inwardly arcuate; tenth tergite apically rounded; spiculum gastrale (Figs 51-52) similar to that of Exaesiopus grossipes . Aedeagus (Figs 53-54) short and stout, slightly dilated apically; apex with pseudopores; parameres fused on their apical half. Basal piece of aedeagus short; ratio basal piece: parameres approximately 1:4.

Differential diagnosis.

Exaesiopus henoni is most similar to the species Exaesiopus laevis and Exaesiopus therondi , with which it shares the shape of protibia (see also Key to species for details). From Exaesiopus therondi it differs by sparsely punctate pronotum, frons that is devoid of tiny irregular rugae, and anterior face of protibia, which is glabrous in Exaesiopus henoni , whereas it is obscurely variolate in Exaesiopus therondi . From Exaesiopus laevis it differs by punctate body (almost impunctate in Exaesiopus laevis ) and present inner subhumeral stria (absent from Exaesiopus laevis ). From the remaining species of the genus Exaesiopus henoni differs by the shape of the protibia (see also Key to species for details).

Biology.

A typical psammophile, found in sand.

Distribution.

So far known only from Algeria and Morocco ( Gomy et al. 2011). New to Libya and Djibouti.