Tomogenius kuscheli Dahlgren, 1976

Lackner, Tomas & Leschen, Richard A. B., 2017, A monograph of the Australopacific Saprininae (Coleoptera, Histeridae), ZooKeys 689, pp. 1-263 : 187-191

Tomogenius kuscheli Dahlgren, 1976 Figs 660, 661-669, 670-678, 766

Tomogenius kuscheli Dahlgren, 1976: 409, fig. 22B.

Type locality.

New Zealand: Stephens Island.

Type material examined.

Tomogenius kuscheli Dahlgren, 1976: holotype, ♀, side-mounted on a triangular card, both protarsi broken off, with the following labels: "Stephens I / Nelson 16 Feb. 76 / G.W. Ramsay" (printed); followed by: “Litter” (printed); followed by: " Tomogenius / sp. n. 1 / Kuschel det. 1974" (written-printed); followed by: "HOLOTYPE / TOMOGENIUS / KUSCHELI / G. DAHLGREN / 30.12.1975" (written); followed by: “HOLOTYPE” (red label, printed); followed by: "Entomology / Division / D.S.I.R / New Zealand" (olive label, printed) (NZAC).

Additional material examined.

NEW ZEALAND. South Island. SD: 1 ♀, Motuara Island, 23.i.1971, J. R. Jackson (ex Puffinus gavia nest) (AMNZ); 3 ♂♂ & 2 ♀♀, ditto, but LUNZ (1 ♂ in coll. TLAN); 1 spec., Stephens Island, Keepers Bush, 20.ii.1994, J.W.M. Marris (ex petrel burrow) (LUNZ).

Biology.

Found in the burrow of a petrel and a shearwater ( Puffinus gavia ).

Distribution.

New Zealand, South Island (SD) Stephens and Motuara Islands (Fig. 766).

Remarks.

Several specimens from the Motuara Island have a short stria next to humeral elytral stria, which may be homologous with the first dorsal elytral stria. However, in the Saprininae , often the humeral elytral stria is doubled and it is therefore difficult to determine exact homology of this stria. Its basal end is not hooked as in the other dorsal elytral striae; it is less deeply impressed and is not on par with the humeral elytral stria regarding its length. This species is most similar to T. australis , especially by the structure of prosternal keel, elytral punctation, or the doubled first striae (compare Figs 622 and 665 or 619 and 660).

Re-description.

Body length: PEL: 4.00-4.40 mm; EL: 2.25-2.75 mm; APW: 1.25-1.50 mm; PPW: 2.75-3.00 mm; EW: 3.25-3.50 mm.

Body (Fig. 660) ovoid, moderately convex, pronotum narrower than elytra; cuticle without metallic luster, dark brown to black; legs, antenna and mouthparts dark brown.

Antennal scape (Fig. 661) not particularly thickened, lower margin carinate, with few short setae; club (Fig. 662) rounded, rather small, entirely covered in dense short sensilla, intermingled with sparser longer erect sensilla; ventral side of antennal club with two pairs of slit-like orifices, sensory structures situated within antennal club not examined.

Mandibles finely and sparsely punctate, rounded, acutely pointed, sub-apical tooth on inner margin of left mandible rather small, obtuse; labrum slightly convex, almost even, not depressed medially, with several punctures (especially on basal half); each labral pit with two moderately long labral setae; terminal labial palpomere elongated, its width about one-fourth its length; mentum (Fig. 663) sub-trapezoid, anterior angles slightly produced, anterior margin with a deep median emargination, surface around it with several longer setae, lateral margins with a single one row of much shorter sparse ramose setae, disc with few scattered setae, median part of mentum almost smooth; cardo of maxilla with few short setae on lateral margin; stipes triangular, with several setae; terminal maxillary palpomere elongated, its width about one-fourth its length, about three times as long as penultimate palpomere; rest of mouthparts not examined.

Clypeus (Fig. 661) large, rectangular, even, rounded laterally, with very dense shallow elongate punctures, separated by less than half their diameter; frontal and supraorbital striae absent; frontal disc (Fig. 661) with punctures similar to those of clypeus, becoming more rounded and sparser posteriorly; eyes flattened, visible from above.

Pronotal sides (Fig. 660) feebly convergent anteriorly, apical angles prominent, marginal pronotal stria complete, thin, slightly carinate; disc entirely with punctation, becoming coarser and denser laterally where punctures very coarse and dense separated by less than their diameter, interspaces with isodiametric structures, medially punctures becoming finer and sparser separated by several times their diameter; along pronotal base an irregular row of larger punctures present; distinct pre-scutellar depression present; pronotal hypomeron glabrous; scutellum small.

Elytral epipleura with small punctures and irregular strioles; marginal epipleural stria double, both striae well impressed, complete; marginal elytral stria well impressed, shortly present also along elytral base, apically continuous along elytral apex as fine, complete apical elytral stria; humeral elytral stria deeply impressed on basal third (occasionally doubled), surface around it deeply striolate; inner subhumeral stria absent; elytral disc with three dorsal elytral striae 2-4, first dorsal elytral stria absent, second to fourth striae well impressed, impunctate, slightly surpassing elytral half; between fourth dorsal elytral and sutural striae a characteristic hooked appendix present; sutural elytral stria present on basal eighth as a short fragment. Elytral disc on basal half (roughly) with punctures separated several times their diameter (fourth elytral interval almost impunctate), on apical half (roughly) punctures becoming larger and denser, laterally extremely aciculate, confluent, interspaces imbricate.

Propygidium (Fig. 664) transverse, about four times as broad as long, partially covered by elytra, with dense and coarse punctures separated by less than their diameter; pygidium (Fig. 664) with similar round punctures, becoming sparser and finer towards apex.

Anterior margin of median portion of prosternum (Fig. 665) rounded; marginal prosternal stria present only laterally; prosternal process between carinal prosternal striae flattened, broad, anterior third elevated, slightly projecting, laterally with sparse shallow oval punctures, intermingled with alutaceous microsculpture, apically and between carinal prosternal striae punctures sparse and microscopic; carinal prosternal striae (Fig. 665) slightly bisinuate, terminating in large and deep apical foveae separated by apex of prosternal keel (Fig. 665); lateral prosternal striae carinate, bisinuate, convergent anteriorly, apically terminating near apical foveae.

Discal marginal mesoventral stria well impressed, somewhat carinate, anteriorly medially projected; disc flattened, laterally with deep large punctures separated several times their diameter becoming finer and even sparser, intermingled with sparse microscopic punctures; meso-metaventral suture distinct, meso-metaventral sutural stria well impressed, undulate, slightly distanced from meso-metaventral suture.

Intercoxal disc of metaventrite convex, finely and sparsely punctate, punctures in apical and basal corners becoming larger and coarser. Lateral metaventral stria well impressed, carinate, almost straight, not reaching metacoxa; lateral disc of metaventrite (Fig. 666) flattened, with sparse shallow punctures; metepisternum + fused metepimeron (Fig. 666) evenly with much coarser and denser punctation; lateral metepisternal stria absent.

Intercoxal disc of first abdominal ventrite completely striate laterally; disc laterally with dense and coarse punctation becoming sparser and finer medio-apically.

Protibia (Fig. 667) almost identical to that of T. australis , differing from it only by areolate outer part of posterior surface of protibia (Fig. 668) (as opposed to smooth in T. australis ) and by the presence of two-three irregular rows of short setae on median part of posterior surface of protibia (as opposed to two dense rows of minuscule setae in T. australis ). Meso- and metatibiae (Fig. 669) basically identical to those of T. australis .

Male genitalia. Eighth sternite (Figs 670-671) widely separated medially, their apices with a tuft of long regular setae arranged in two rows; eighth tergite (Fig. 671) only slightly larger than sternite, apically faintly inwardly arcuate; basal margin strongly inwardly arcuate. Basal margin of eithth tergite medially with a curious oval structure; 8 th sternite and tergite not fused laterally (Fig. 672). Ninth tergite (Figs 673-674) medially narrowly separated; apical margin of tenth tergite straight. Spiculum gastrale (Figs 675-676) with almost parallel body and dilated ends: apical end strongly sclerotized; basal margin cordate. Aedeagus (Figs 677-678) almost parallel-sided, apical fifth roundly dilated; parameres fused almost along their entire length. Basal piece of aedeagus rather short, its ratio to ratio of parameres approximately 1:4.