Hypocaccus (Baeckmanniolus) laevis Thérond, 1963

Lackner, Tomáš, 2013, Hypocaccus (Baeckmanniolus) laevis Thérond, 1963 is not synonymous with H. (B.) virescens Thérond, 1963 (Coleoptera: Histeridae: Saprininae), Zootaxa 3731 (1), pp. 183-192 : 184-186

Hypocaccus (Baeckmanniolus) laevis Thérond, 1963 stat. restit.

( Figs. 1–9 )

Baeckmanniolus laevis Thérond, 1963: 111 .

Hypocaccus (Baeckmanniolus) laevis: Mazur, 1984: 100 .

Type locality. Somalia, Mudugh [=Mudug] region: Obbia [=Hobyo].

Type material examined. Holotype (NHMB), ♀, mounted on its side on triangular point, both antennal clubs, right protibia, right mesotibia missing, with printed label: “Obbia SOMALIA / Mudugh VIII.1958 / C. KOCH”; another label (printed-written): “J. Thérond det. 1962 / Baeckmanniolus / laevis nov. sp.”; another printed label: “Museum Frey / Tutzing”; with another pink, pencil-written label: “D07-069”; and another red, written label: “ HOLOTYPUS / Baeckmanniolus / laevis Thérond, 1963 / label attached by / T. Lackner 2008”. Paratype (MNHN), ♀, side-mounted on triangular point, right protarsus, left protibia missing, right mesotibia broken off, glued to the same point as specimen, both metatarsi missing, with printed label: “Obbia SOMALIA / Mudugh VIII.1958 / C. KOCH”; followed by another printed label: “Museum Frey / Tutzing”; and another red, hand-written label: “ Paratype ”; followed by another hand-written label: “ Baeckmanniolus / laevis / Thérond.

Other material examined. 1 ♀ (BMNH): “Nyali Bch. / 23.V.1955 / V.F. Easton; C.E. Tottenham / collection. /B.M. 1974-587”.

Remark. Thérond (1963) mentioned that the holotype had been deposited at NHMB, while he apparently kept the paratype in his collection, now deposited at MNHN (although he does not mention this explicitly in the text). Therefore, I labelled the specimen from NHMB as the holotype despite the fact that it did not have a type label attached.

Re-description. Body length: PEL: 1.75–1.85 mm; APW: 0.75–0.80 mm; PPW: 1.30–1.35 mm; EL: 0.95– 1.00 mm; EW: 1.45–1.55 mm. Body ( Figs. 1–2 ) rectangular oval, convex, cuticle light brown to slightly red, elytra somewhat lighter than pronotum, legs and antennal scape rufo-castaneous.

Mouthparts. Mandibles ( Fig. 3 ) stout, outer margin rounded, upper margin carinate; disk of labrum with two well-impressed pits, each with two setae; width of terminal labial palpomere about one-third its length; mentum ( Fig. 4 ) square-shaped, without emargination in middle of anterior margin; anterior margin with several setae, lateral margins with a single row of short ramose setae; disk of mentum with few short ramose setae becoming more setose along margins. Cardo of maxilla with two short setae on lateral margin; stipes triangular, with three longer setae; terminal maxillary palpomere somewhat thickened, its width about one-third its length, approximately twice as long as penultimate; other parts of mouth not examined.

Clypeus + frons. Clypeus ( Fig. 3 ) rectangular, somewhat depressed medially, anterior margin elevated; frontal stria well impressed, straight, carinate, continued as strongly carinate supraorbital stria. Frons smooth, medially with single deeply marked chevron, anterior to it two short fragments of rugae present; eyes flattened, almost invisible from above.

Pronotum. Pronotal sides ( Fig. 1 ) almost parallel on basal half, thence moderately convergent anteriorly, apical angles produced, anterior emargination for head deep, almost straight in middle; marginal pronotal stria complete, on apical half slightly carinate; disk entirely smooth except for a single row of round punctures along base; pronotal hypomeron smooth; scutellum small, visible.

Elytra + propygidium and pygydium. Elytral epipleura almost impunctate; marginal epipleural stria complete, very fine; marginal elytral stria deeply impressed, continued as well impressed complete apical elytral stria. Humeral elytral stria well impressed on basal third; inner subhumeral stria absent; elytral disk with four finely impressed finely punctate dorsal elytral striae 1-4, slightly surpassing elytral half, fourth one basally well connected with sutural elytral stria; sutural elytral stria well impressed and complete, apically connected to apical elytral stria. Punctuation of elytral disk limited to small apical area near sutural elytral stria on apical third; punctures very fine, sparse, separated by several times their own diameter. Punctuation of propygidium and pygidium denser and coarser than that of elytra, punctures separated by about two times their own diameter; pygidial apex smooth.

Prosternum. Anterior margin of median portion of prosternum ( Fig. 5 ) rounded, prosternal foveae deeply impressed and large. Prosternal process slightly concave with sparse punctures of irregular sizes; interspaces with isodiametric structures. Lateral prosternal striae well impressed, convergent anteriorly, united in front; carinal prosternal striae slightly carinate, slightly divergent between procoxae, thence running almost parallel, vaguely united in front.

Meso-metaventrite + metepisternum and abdomen..Anterior margin of mesoventrite weakly emarginated medially; marginal mesoventral stria well impressed, carinate laterally, anteriorly somewhat weakened; mesometaventral suture weakly impressed, straight. Disk of mesoventrite flat, smooth; intercoxal disk of metaventrite smooth, basally covered with irregular sparse microscopic punctures. Lateral metaventral stria well impressed, carinate, slightly bisinuate, stopping near metacoxa. Lateral disk of metaventrite ( Fig. 6 ) excavate, with shallow sparse punctures of various sizes, fringed with very short setae; metepisternum with coarser and denser punctures, fringed with minute setae. Intercoxal disk of the first abdominal ventrite completely striate laterally; almost smooth, only with sparse minute punctures along basal margin.

Legs. Protibia ( Fig. 7 ) slightly dilated, outer margin with two large triangular distal teeth topped by rounded triangular denticle, followed by two smaller teeth, diminishing in size posteriorly, topped by denticle and followed by two minuscule denticles; outer row of setae regular, setae well-sclerotized and approximately similar in length; protarsal groove deep; protibial stria almost complete; median row of setae regular, setae shorter than those of outer row; outer part of posterior surface with irregular rugae divided from median part of posterior surface by definite boundary and two well-distanced minuscule denticles; posterior protibial stria terminating in two short lamellate setae and single thick inner posterior denticle; setae of inner row lamellate, regular and growing in size apically; protibial spur minute, growing out from apical protibial margin; apical margin of protibia with two well-separated minuscule apical denticles. Mesotibia ( Fig. 8 ) slender, outer margin with two differently-sized rows of approximately seven denticles in each row, growing in size apically; outer row of setae sparse, setae long and wellsclerotized, as long or longer than the denticles of the longer row of outer margin themselves; setae of median row sparse, shorter and thinner than those of outer row; anterior surface of mesotibia almost glabrous, only with sparse minuscule punctures; anterior mesotibial stria almost complete, shortened apically; mesotibial spur welldeveloped; claws of apical tarsomere broken off. Metatibia ( Fig. 9 ) in all aspects similar to mesotibia but more slender; outer row of setae absent; setae of median row longer than those of mesotibia and denticles on outer margin sparser and shorter.

Male unknown.

Distribution. Somalia, Mudug province, newly recorded from Kenya ( Mombasa env.) ( Fig. 29 ).

Biology. As typical for the members of the subgenus Baeckmanniolus , the type series as well as the third known specimen were collected on beach.

Comment. Thérond (1963) mentions that this species is larger than H. (B.) virescens and differs from it (and from all known congeners, for that matter) by completely smooth elytra. Having examined the holotype and paratype, I can conclude that these statements are not supported by the observation of the type specimens. The size of H. (B.) laevis is smaller than that of H. (B.) virescens and elytra of H. (B.) laevis are furnished with a small apical area of very small and scattered punctuation. The main differences between the two species are outlined in the table below.

Figures

FIGURE 29. Distributional map of Hypocaccus (Baeckmanniolus) virescens Thérond, 1963 and H. (B.) laevis Thérond, 1963.

FIGURES 1 – 9. Hypocaccus (Baeckmanniolus) laevis Thérond, 1963, SEM micrographs: 1 — habitus, dorsal view; 2 — ditto, ventral view; 3 — head, dorsal view; 4 — mentum, ventral view; 5 — prosternum; 6 — lateral disk of metaventrite + metepisternum; 7 — protibia, dorsal view; 8 — mesotibia, dorsal view; 9 — metatibia, dorsal view.