Iridoprinus myrmecophilus, Lackner, Tomas & Leschen, Richard A. B., 2017

Lackner, Tomas & Leschen, Richard A. B., 2017, A monograph of the Australopacific Saprininae (Coleoptera, Histeridae), ZooKeys 689, pp. 1-263 : 43-45

Iridoprinus myrmecophilus sp. n. Figs 202, 203-211, 212-218, 757

Type locality.

Australia: Coniston Station near Alice Springs.

Type material examined.

Holotype, ♂, side-mounted on a triangular card with male genitalia glued to the same card as specimen with the following labels: "Coniston Station, / near Alice Springs / N.W. Mules" (printed), with hand-written text on the reverse side: "Nov 1. Dec.31 1931"; "Good/ Saprinus " (hand-written); followed by: " SAMA Database/No.25-029415" (printed); followed by: “10-157” (yellow, pencil-written label added by the senior author); followed by: " Iridoprinus / myrmecophilus / n. gen. & sp. / HOLOTYPE / det. T. Lackner 2010 " (red label, written) (SAMA). Paratype, ♀, labelled: "AUSTRALIA / Kudgee / 16.xii.[19]72 / B.P. Moore (printed-written), with written text on the reverse side: "In nest of Iridomyrmex purpureus "; followed by: “10-139” (yellow, pencil-written label added by the senior author); followed by: " Iridoprinus / myrmecophilus / n. gen. & sp. / PARATYPE / det. T. Lackner 2010 " (red label, written) (ANIC).

Description.

Body length (only 1 specimen, the holotype was measured): PEL: 3.00 mm; APW: 0.85 mm; PPW: 2.35 mm; EL: 2.00 mm; EW: 2.65 mm.

Body (Fig. 202) rectangular oval, moderately convex from above, underside slightly flattened, cuticle light brown, pronotum rufous, elytra with blue iridescent metallic luster; legs and body appendages rufo-castaneous.

Antennal scape (Fig. 203) triangular, thickened, with several setae; club (Fig. 204) rather large, balloon-shaped, on apical two-thirds with short dense sensilla intermingled with sparse longer erect sensilla; sensory structures of antennal club not examined.

Mandibles with almost rectangular outer margin, acutely pointed, sub-apical tooth on inner margin of left mandible obtuse; mentum sub-trapezoid, anterior margin almost straight, without notch; other parts of mouth not examined.

Clypeus (Fig. 203) dorsally flattened, rounded laterally, with fine elongated punctures, separated by several times their diameter; supraorbital stria well developed, frontal stria carinate, prolonged onto clypeus; frontal disc (Fig. 203) densely punctuate, punctures deep, separated by about their diameter becoming elongate anteriorly, interspaces imbricate; eyes convex, well visible from above.

Pronotal sides (Fig. 202) feebly convergent anteriorly, apical angles obtuse, marginal pronotal stria present, laterally carinate, absent behind head; disc behind head with almost glabrous triangularly shaped ‘mirror’ (=polished area) with only scattered microscopic punctures, rest of pronotal disc coriarious-punctate, punctures becoming denser and coarser laterally, forming confluent elongate wrinkles; pronotal hypomeron glabrous; scutellum small, well visible.

Elytral epipleuron with microscopic punctures furnished with short setae; marginal epipleural and marginal elytral striae well impressed, complete; marginal elytral stria carinate, continuous along elytral apex as weakened apical elytral stria; humeral elytral stria inconspicuous (absent?); inner subhumeral stria absent; elytral disc with five curved strongly carinate dorsal elytral striae 1-5, striae sub-equal in length, fifth stria the shortest; sutural elytral stria absent. Entire elytral disc coarsely and very densely punctate, punctures rugulose, separated by less than half their diameter, each puncture with microscopic yellow seta well visible from lateral view.

Propygidium (Fig. 205) transverse, about four times as broad as long, partially covered by elytra, its punctation somewhat less dense and coarse than that of the elytra, punctures adorned with setae; pygidium (Fig. 205) with similarly dense and coarse setigerous punctures like those of the elytra, becoming sparser and finer towards apex.

Anterior margin of median portion of prosternum (Fig. 206) almost straight; marginal prosternal stria interrupted; prosternal process flattened, interspace between carinal prosternal striae excavated, smooth, laterally with scattered microscopic punctation, each puncture with minuscule seta; carinal prosternal striae (Fig. 206) divergent on both ends, united anteriorly; lateral prosternal striae carinate, almost straight, attaining apices of united carinal prosternal striae.

Anterior margin of mesoventrite (Fig. 207) almost straight; discal marginal mesoventral stria present only anteriorly, straight; disc flattened, with dense small punctures separated by about their own to twice their diameter, each puncture with microscopic seta, interspaces with alutaceous micro-sculpture; meso-metaventral suture distinct, straight, meso-metaventral sutural stria absent; intercoxal disc of metaventrite completely covered with punctation identical to that of mesoventrite, but interspaces without micro-sculpture. Lateral metaventral stria (Fig. 208) well impressed, shortened, carinate, curved outwardly; lateral disc of metaventrite (Fig. 208) excavated, with confluent shallow elongate punctures fringed with microscopic setae; metepisternum on apical half with deep longitudinal groove (Fig. 208) designed for accommodating mesotarsus, surface of metepisternum glabrous; fused metepimeron with scattered shallow punctures; lateral metepisternal stria present only on fused metepimeron, on metepisternum several large deep elongate punctures present.

Intercoxal disc of first abdominal ventrite completely striate laterally; surface of disc with punctation identical to that of mesoventrite, interspaces with alutaceous microsculpture.

Protibia (Fig. 209) flattened and dilated, outer margin almost without teeth, with 12-14 short thin denticles; setae of outer row short, sparsely paced; median row of setae absent; protarsal groove narrow but deep; anterior protibial stria absent; two thin, very short tarsal denticles present apically; protibial spur minute, growing out from apical protibial margin; outer and median part of posterior surface of protibia (Fig. 210) with several irregular rows of minute setae; demarcation line between outer and median part of posterior surface absent; posterior protibial stria complete, with regularly spaced minuscule setae turning into several thicker setae apically; inner margin with regular row of short setae becoming thicker apically.

Mesotibia (Fig. 211) dilated, outer margin with five widely spaced short denticles growing in size apically; setae of outer row sparse, regular, thin; setae of median row indistinguishable, entire posterior surface of protibia with several irregular rows of minuscule setae; posterior mesotibial stria inconspicuous (absent?); anterior surface of mesotibia with several irregular rows of minuscule setae; mesotibial spur stout, short; apical margin with two tiny denticles; claws of apical tarsomere about half its length; metatibia more slender than mesotibia, outer margin with only two short proximal denticles, in all other aspects similar to mesotibia.

Male genitalia. Eighth sternite (Figs 212-213) apically longitudinally separated medially; vela absent, eighth sternite apically with several setae; eighth tergite and eighth sternite not fused laterally (Fig. 214). Ninth tergite (Fig. 215) longitudinally fused medially; spiculum gastrale (Fig. 215) gradually dilated in most of apical half, basal half moderately dilated, rounded. Aedeagus (Figs 217-218) conspicuously long compared to eighth sternite and tergite, slender; basal piece of aedeagus short, ratio of its length: length of parameres 1: 6; parameres fused along their basal three-fourths; aedeagus slightly curved from lateral view (Fig. 218).