Tomogenius australis Dahlgren, 1976

Lackner, Tomas & Leschen, Richard A. B., 2017, A monograph of the Australopacific Saprininae (Coleoptera, Histeridae), ZooKeys 689, pp. 1-263 : 177-181

Tomogenius australis Dahlgren, 1976 Figs 619, 620-628, 629-637, 766

Tomogenius australis Dahlgren, 1976: 409, fig. 22C, F.

Type locality.

New Zealand: Motunau Island.

Type material examined.

Tomogenius australis Dahlgren, 1976: holotype, ♂, terminalia extracted and dismembered and glued to the same mounting card as the specimen, right metatarsus missing, with following labels: "Motanau Is. / 23.10.[19]63 / In Petrel burrow / B.A. Tunncliffe" (written); followed by: " Tomogenius / n.sp. 2" (written-printed); followed by: "HOLOTYPE / TOMOGENIUS AUSTRALIS / G. DAHLGREN / 30.12.1975" (written); followed by: "Entomology / Division / D.S.I.R. / New Zealand" (golden label, printed); followed by: “HOLOTYPE” (bright red label, printed); followed by: "NZ Arthropod Collection / barcode / NZAC04039485" (printed) (NZAC). Paratype, ♀, side-mounted on a triangular card, with following labels: "Motanau Is. / 22.10.[19]63 / In Petrel burrow / B.A. Tunncliffe" (written); followed by: "PARATYPE / TOMOGENIUS AUSTRALIS / G. DAHLGREN / 30.12.1975" (written); followed by: " Tomogenius australis / Dahlgren, 1976 / (PARATYPE) / Det. S. E. Thorpe, 2002" (printed); followed by: "Entomology / Division / D.S.I.R. / New Zealand" (golden label, printed); followed by: “09-084” (yellow, pencil-written label added by the senior author) (NZAC).

Additional material examined.

New Zealand: 1 spec., Motanau Island, 23.x.1963, G. Tunncliffe leg., in Petrel burrow (MNHN, coll. Thérond).

Biology.

Found in a petrel burrow.

Distribution.

New Zealand, South Island (NC), Motunau Island (Fig. 766).

Remarks.

This species is most similar to T. kuscheli , especially by the structure of prosternal keel, elytral punctation, and the doubled first dorsal elytral stria (compare Figs 622 and 665 or 619 and 660). T. australis is known only from the type series collected in a petrel burrow on Motunau Island, South Island, New Zealand. Although the original label reads “Motanau”, the correct name of the island is “Motunau”. Motunau Island is an important site for seabirds.

Re-description.

Body length: PEL: 3.75-4.10 mm; EL: 2.40-2.65 mm; APW: 1.25-1.60 mm; PPW: 2.50-2.60 mm; EW: 3.00-3.25 mm.

Body (Fig. 619) ovoid, moderately convex, pronotum narrower than elytra; cuticle without metallic luster, castaneous to dark brown, pronotum darker than elytra, almost black; legs, antennae and mouthparts rufous-brown.

Antennal scape (Fig. 620) not particularly thickened, lower margin carinate, with few short setae; club rather oval, entirely covered in dense short sensilla, intermingled with sparser longer erect sensilla; sensory structures of antennal club not examined.

Mandibles finely microscopically punctate, with rounded outer margin, acutely pointed, sub-apical tooth on inner margin of left mandible rather small, obtuse; labrum slightly convex with indistinct median costiform elevation, not depressed medially, with several punctures (especially on basal half) each labral pit with a single moderately long labral seta; terminal labial palpomere elongated, its width about one-fourth its length; mentum (Fig. 621) sub-trapezoid, anterior angles slightly produced, anterior margin with a deep median emargination, surface around it with five tightly spaced long 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 seven 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. 620) large, rectangular, even, rounded laterally, with sparse fine punctures, separated by several times their diameter; frontal and supraorbital striae absent; frontal disc (Fig. 620) with sparse fine round punctures similar to those of clypeus; eyes flattened, visible from above.

Pronotal sides (Fig. 619) feebly convergent anteriorly, apical angles obtuse, marginal pronotal stria complete, thin, slightly carinate, somewhat weakened behind head; disc entirely with punctation, becoming coarser and denser laterally where punctures are separated by less than their diameter, medially becoming finer and sparser separated by several times their diameter; along pronotal base a triple row of larger punctures present; pronotal hypomeron glabrous; scutellum very small.

Elytral epipleura impunctate; marginal epipleural stria double, both striae well impressed, complete; marginal elytral stria well impressed, continuous along elytral apex as weakened but complete apical elytral stria; humeral elytral stria well impressed on basal third, surface around it striolate; inner subhumeral stria absent; elytral disc with four dorsal elytral striae 1-4, first the shortest, only as long as humeral elytral stria (situated near it) and in the case of the female paratype continued as a vague intermittent impression, 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 tenth 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, but still rather sparse; on apical third punctures strongly aciculate, especially laterally.

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

Anterior margin of median portion of prosternum (Fig. 622) 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 much smaller but denser; carinal prosternal striae (Fig. 622) parallel, terminating before large and deep widely separated apical foveae; lateral prosternal striae carinate, convergent anteriorly, apically terminating in apical foveae.

Discal marginal mesoventral stria (Fig. 623) well impressed, somewhat carinate, anteriorly medially projected; disc flattened, laterally with deep large punctures separated several times their diameter becoming finer and even sparser; meso-metaventral suture distinct, meso-metaventral sutural stria well impressed, undulate.

Intercoxal disc of metaventrite in males with small narrow longitudinal furrow before hind margin, in females without such furrow, slightly 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. 624) flattened, with sparse shallow punctures; metepisternum + fused metepimeron (Fig. 624) evenly with much coarser and denser punctation; lateral metepisternal stria present, deeply impressed and almost complete.

Intercoxal disc of first abdominal ventrite completely striate laterally; surface of disc on basal half with scattered punctation, punctures becoming sparser and finer apically.

Protibia (Fig. 625) flattened and somewhat dilated, outer margin with six low triangular teeth followed by three tiny denticles; first two teeth conspicuously larger than the remaining ones (and separated by a wide gap) that are diminishing in size in proximal direction; teeth topped by short denticle; first (distal-most) tooth topped by double denticle. Setae of outer row short, moderately dense; setae of median row similarly dense and regular, slightly shorter than those of outer row; protarsal groove shallow; anterior protibial stria complete, costate; two thin, rather long tarsal denticles present apically; protibial spur moderately long, not particularly bent, growing out from apical protibial margin; apical margin of protibia posteriorly with two tiny apical denticles; outer part of posterior surface of protibia (Fig. 626) smooth, well divided from median part of posterior surface by ridge like stria; median part of posterior surface with two dense rows of minuscule setae; posterior protibial stria complete with tightly-spaced short and stout denticles near apical margin; inner margin with double row of short setae.

Mesotibia slender, outer margin with a single row of dense thin denticles growing in size apically; setae of outer row regular, rather dense but short, growing somewhat longer apically; setae of median row irregular, much shorter than those of outer row; posterior mesotibial stria complete; anterior surface of mesotibia with another row of denticles shorter, but similar to those of outer margin; a row of microscopic setae situated below it; anterior mesotibial stria (Fig. 627) complete, terminating in three tiny inner anterior denticles; mesotibial spur stout, short; apical margin with two tiny denticles; mesotarsus shorter than mesotibia; claws of apical tarsomere bent, longer than half its length; metatibia (Fig. 628) basically similar to mesotibia, but denticles of outer margin sparser and finer than those of mesotibia.

Male genitalia. Eighth sternite (Figs 629-630) completely fused medially; apically with a single row of tightly spaced long setae diminishing in size mesally; vela present, apically with another row of shorter but similarly dense setae; eighth tergite and eighth sternite fused laterally (Fig. 631); eighth tergite medially inwardly arcuate. Ninth tergite (Figs 632-633) longitudinally divided medially; outer margin of tenth tergite slightly arcuate inwardly, almost straight; spiculum gastrale (Figs 634-635) abruptly dilated on apical third, basal end abruptly dilated, cordate. Aedeagus (Figs 636-637) slender, almost parallel-sided, slightly dilated on apical fifth and thence convergent apically; apex of aedeagus not pointed, straight; basal piece of aedeagus short, ratio of its length: length of parameres 1:5; parameres fused almost along their entire length, only on apical fifth with an opening for median lobe; aedeagus slightly curved from lateral view (Fig. 637).