Chalcionellus libanicola ( Marseul, 1870 )

Lackner, Tomáš, 2011, On the identity of Chalcionellus orcinus and Chalcionellus libanicola (Coleoptera: Histeridae), Acta Entomologica Musei Nationalis Pragae 51 (2), pp. 505-515 : 511-514

Chalcionellus libanicola ( Marseul, 1870)

( Figs. 17–21 , 22–29 )

Saprinus libanicola Marseul, 1870: 113 .

Chalcionellus libanicola: REICHARDT (1932: 141) ; MAZUR (1984: 82); MAZUR (1997a: 32); MAZUR (1997b: 247); MAZUR (2004: 91).

Type locality. Lebanon.

Type material examined. LECTOTYPE (by present designation): specimen of unknown sex, but possibly a female, since it lacks the median longitudinal line on the metaventrite that is typical for males of this genus ( MNHN): all legs and antennae missing, head, labrum, both mandibles, both elytra, thorax and parts of abdomen glued on a mounting card, bearing the following labels: with rounded yellow label (written): ‘ Saprinus / libanicola / m. Liban / Coq. ’68’; with another printed label: ‘Museum Paris / Coll. De Marseul / 2842-90’; followed by another label, red-printed: ‘TYPE’; followed by another printed-written label: ‘ Chalcionellus / libanicola / 1996 det. S. Mazur’; followed by another red label (written): ‘ Saprinus / libanicola / Marseul, 1872 / LECTOTYPE / des. T. Lackner ’09’ Additional material examined. SYRIA: 1 J, Seron? Syrie, Coye ( BMNH). TURKEY: 1 J, Konya, Sertavul Geçidi [= Sertavul Pass], 1500-1600m, 25.iv.[19]78, / Besuchet Löbl ( MNHG).

Differential diagnosis. Chalcionellus libanicola differs from Ch. orcinus by the following characters depicted in Table 1 as well as by the differently shaped spiculum gastrale that is apically more dilated in Ch. libanicola than in Ch. orcinus and aedeagus that is slightly more contracted before apex (compare Figs. 14–15 and 26–27 ).

Redescription (based on the lectotype). Very similar to the preceding species, but slightly larger; body length: 2.50 mm; width: 1.80 mm. Labrum and mentum likewise similar; labrum ( Fig. 19 ) imbricate-punctate, somewhat depressed anteriorly; anterior margin of mentum ( Fig. 21 ) with shallow median notch, surface around it fringed with several long setae, lateral margins with double row of much shorter setae, disc of mentum with scattered short setae. Clypeus also similar to that of Ch. orcinus , but not depressed, flat; frontal disc covered with moderately coarse and dense punctuation, punctures separated by about their own diameter, on anterior half of frontal disc slightly depressed, interspaces between punctures with alutaceous microsculpture, this microsculpture also present on entire clypeus; on posterior fifth, near occipital stria medially with single deep fovea. Rest of frons and clypeus as with Ch. orcinus . Pronotal sides similar to Ch. orcinus , but almost parallel on posterior two-thirds, on apical third slightly convergent apically, apical angles obtuse. Pronotum very similar to that of preceding species, but punctuation not forming a lateral band like in Ch. orcinus . Elytral color light brown, shining, with metallic luster. Elytra ( Fig. 17 ) very similar to that of Ch. orcinus , but the configuration of elytral striae somewhat different: first and third striae about the same length, not reaching elytral half apically, second and fourth striae longer, reaching approximately elytral half apically; elytral striae 1–3 in tiny shallow, almost inconspicuous punctures, fourth stria in much coarser and larger punctures; sutural elytral stria fine, thin, reaching approximately four-fifths of elytral length apically, next evanescent. Approximately apical elytral half covered with rather sparse elongate punctures, separated by about twice their diameter; on basal half and lateral sides of elytra (roughly) punctuation becomes much finer and sparser, punctures separated several times their diameter. Prosternum ( Fig. 20 ): marginal prosternal stria absent; lateral sides of prosternal process substrigulate-punctate; lateral prosternal striae costiform; rest of prosternum as with Ch. orcinus . Mesoventrite and metaventrite: marginal mesoventral stria slightly emarginate anteriorly; discs with scattered microscopic punctures; rest of meso- and metaventrite otherwise identical to those of preceding species.

Male genitalia (based on the specimen from Syria): Very similar to those of Ch. orcinus , but eighth sternite ( Figs. 22–23 ) widely separated medially; apex of eighth sternite laterally with several rows of short sparse setae; eighth tergite and sternite fused laterally ( Fig. 24 ). Morphology of 9 th and 10 th tergites ( Figs. 25–26 ) similar to those of Ch. orcinus , but spiculum gastrale ( Fig. 26 ) more dilated apically than in Ch. orcinus . Basal piece of aedeagus ( Figs. 29 ) and aedeagus ( Figs. 27, 28 ) also very similar between the two species.

Remarks. MARSEUL (1870) mentioned that there were multiple specimens of this species available, but presently only a single specimen remains in the MNHN collection. This specimen is therefore designated as the lectotype.

Distribution. Lebanon (Mount Lebanon mountain range), Turkey (Sertavul Pass, between cities Karaman and Mersin) and Syria (illegible locality).

Figures

Figs. 17–21: Chalcionellus libanicola (Marseul, 1870). 17 – right elytron, dorsal view; 18 – left mandible, dorsal view; 19 – labrum, dorsal view; 20 – prosternum; 21 – mentum, ventral view.

Figs. 22–29: Chalcionellus libanicola (Marseul, 1870). 22 – Eighth sternite and tergite, ventral view; 23 – same, dorsal view; 24 – same, lateral view; 25 – ninth and tenth tergites + spiculum gastrale, lateral view; 26 – ninth and tenth tergites, dorsal view + spiculum gastrale, ventral view; 27 – aedeagus, dorsal view; 28 – same, lateral view; 29 – phallobase (basal piece of aedeagus), lateral view.

Figs. 10–16: Chalcionellus orcinus Reichardt, 1932. 10 – eighth sternite and tergite, ventral view; 11 – same, dorsal view; 12 – same, lateral view; 13 – Ninth and tenth tergites, dorsal view + spiculum gastrale, ventral view; 14 – ninth and tenth tergites + spiculum gastrale, lateral view; 15 – aedeagus, dorsal view; 16 – same, lateral view.