Hypocacculus (Hypocacculus) hyla (Marseul, 1864)

Lackner, Tomas & Leschen, Richard A. B., 2017, A monograph of the Australopacific Saprininae (Coleoptera, Histeridae), ZooKeys 689, pp. 1-263 : 25-28

Hypocacculus (Hypocacculus) hyla (Marseul, 1864) Figs 111, 112, 113-118, 119-127, 755

Saprinus hyla Marseul, 1864: 339.

Type locality.

New Guinea.

Type material examined.

Saprinus hyla Marseul, 1864: Lectotype, present designation: ♀, side-mounted on a triangular card with right metatibia (metatarsus missing) and left antennal club broken off and glued to the same mounting card, left metatibia missing, last two segments of left mesotarsus missing, both protarsi missing, with the following labels: " Saprinus / hyla / N. Guinée / Wallace illegible text" (yellow, round label, written); followed by: " Saprinus / Hyla / N. Guinea" (written); followed by: "MUSEUM PARIS / Coll. De Marseul / 2842-90" (printed); followed by: “TYPE” (red-printed label); followed by: " Saprinus / hyla Marseul, 1864 / LECTOTYPE / Des. by Lackner & / Leschen, 2011" (red label, written) (MNHN). This species has been described from an unknown number of specimens and the lectotype designation fixes its taxonomic identity.

Additional material examined.

PAPUA NEW GUINEA: 1 ♂, Huon Golf, Simbang, 1899, Biró leg. (HNMH). INDIA. Orissa: 1 ♂, Koraput Jeypore, 22.x.2006, G. de Rougemont (NCB).

Biology.

Unknown, probably a saprobiont.

Distribution.

See above (Fig. 755).

Remarks.

The male specimen from India matches the form of the female lectotype, only differing by its color, which is somewhat darker, and the punctation of the elytra, which is less dense apically compared to the New Guinean lectotype.

Re-description.

Body length: PEL: 1.625-1.80 mm; APW: 0.625-0.75 mm; PPW: 1.25-1.625 mm; EL: 1.00-1.25 mm; EW: 1.425-1.75 mm.

Body (Fig. 111) rectangular oval, dorsal surface convex, ventral surface flattened, cuticle light to darker brown with bronze metallic luster, legs, mouthparts and antennae light brown.

Antennal scape (Fig. 113) with lower margin carinate, with two short setae; antennal club (Fig. 113) round, lower half of its surface glabrous, upper half (approximately) with thick short yellow sensilla; sensory structures of antennal club not examined.

Mandibles stout, with rounded outer margin strongly curved inwardly, dorsally with sparse fine punctures, acutely pointed, sub-apical tooth on inner margin of left mandible not examined; labrum punctate, dorsally with median costiform elevation; terminal labial palpomere elongated, its width about one-third its length, about twice as long as penultimate; mentum square-shaped, anterior angles slightly produced, anterior margin with deep median excavation, surface of mentum with sparse setae; stipes triangular, with three short setae; terminal maxillary palpomere elongated, its width about one-third its length, approximately twice as long as penultimate; other mouthparts not examined.

Clypeus (Fig. 113) sub-quadrate, rounded laterally, slightly concave medially, anterior margin slightly carinate, surface mesad to it with dense punctures; frontal stria complete and slightly carinate, slightly outwardly arcuate, continuous with weakly carinate supraorbital stria; frontal disc (Fig. 113) with regular punctation, punctures separated by several times their diameter; eyes slightly flattened, visible from above.

Pronotal sides (Fig. 111) slightly convergent anteriorly, apical angles obtuse; pronotal depressions absent; marginal pronotal stria complete, carinate; disc of pronotum laterally with shallow, moderately dense punctation, punctures become sparser and finer medially; along pronotal base a denser row of ovoid punctures present; pronotal hypomeron with microscopic sparse amber setae; scutellum small, visible.

Elytral humeri not particularly prominent; elytral epipleura with scattered microscopic punctures; marginal epipleural stria complete; marginal elytral stria straight and carinate; apical elytral stria absent. Humeral elytral stria well impressed on basal third; inner subhumeral stria present as a short median fragment; elytral disc with four deeply impressed dorsal elytral striae 1-4, all striae in punctures which are more prominent apically, striae about the same length, somewhat diminishing in length from first to fourth, reaching approximately two-thirds of elytral length apically; fourth elytral stria basally well connected with sutural elytral stria; sutural elytral stria well impressed, almost complete; basal third of elytral disc and elytral flanks only with scattered microscopic punctation, apical two-thirds with much denser and coarser punctation, punctures separated by about twice their diameter, on apical fifth punctation becomes even denser, punctures separated by their own diameter, extreme apex of elytra with a glabrous band.

Propygidium (112) on anterior half almost impunctate, on posterior half with dense punctures separated by about their diameter; pygidium (112) on basal third with punctures separated by about twice their own diameter, punctures becoming sparser and finer apically; extreme apex of pygidium almost impunctate.

Anterior margin of median portion of prosternum (Fig. 114) rounded; prosternal foveae large and deep; marginal prosternal stria present only laterally; prosternal process densely and coarsely punctate; carinal prosternal striae slightly divergent on prosternal apophysis, running parallel, not united apically; lateral prosternal striae carinate, widely united in front of carinal prosternal striae.

Discal marginal mesoventral stria (Fig. 114) anteriorly slightly inwardly arcuate, complete; disc of mesoventrite with deep and dense punctures, separated by about their own diameter, interspaces imbricate; meso-metaventral suture indistinct; meso-metaventral sutural stria bisinuate and undulate, slightly distanced medially from meso-metaventral suture; intercoxal disc of metaventrite on basal three-fourths with scattered fine punctures, in apical third and especially behind metacoxae much larger and deeper punctures present; lateral metaventral stria carinate, almost complete; lateral disc of metaventrite (Fig. 115) slightly excavate, with deep dense punctures of various sizes, apically becoming sparser; metepisternum + fused metepimeron with even denser and coarser setigerous punctures; lateral metepisternal stria present only on fused metepimeron.

Intercoxal disc of first abdominal ventrite almost completely striate laterally; disc laterally and anteriorly with punctures of various sizes, median part of disc almost impunctate, with alutaceous microsculpture.

Protibia (Fig. 116) slightly widening apically, outer margin with seven obtuse teeth topped by prominent denticle, diminishing in size in proximal direction, followed by two minute proximal denticles; setae of outer row thin, sparse, regular; setae of median row even shorter than those of outer row; protarsal groove deep; anterior protibial stria well impressed, bisinuate, shortened apically; protibial spur small, growing out from anterior protibial margin; outer part of posterior surface of protibia (Fig. 117) almost smooth, demarcation line between outer and median of posterior surface marked by double undulate stria, basally that stria with about seven strongly sclerotized setae; median part of posterior protibial surface almost smooth, imbricate, posterior protibial stria complete, fine, apically ending in two short denticles; inner margin with double row of short setae.

Mesotibia slender, outer margin with a row of several thin denticles growing in size apically; setae of outer row strongly sclerotized, about the size of denticles, growing in size apically; setae of median row present medially, much finer and shorter, posterior mesotibial stria not examined; anterior surface of mesotibia with another dense row of short denticles; anterior mesotibial stria straight and complete, terminates in two short denticles; mesotibial spur short; apical margin of mesotibia with three short denticles; claws of apical tarsomere bent, shorter than its half; metatibia (Fig. 118) similar to mesotibia, but denticles on its outer margin even sparser.

Male genitalia (based on a male from India: Orissa; see above). Eighth sternite (Figs 119-120) gradually narrowing apically, entirely fused medially; apex of eighth tergite (Fig. 120) shallowly emarginate; apex of eighth sternite with vela covered with dense microscopic setae. Eighth sternite and tergite fused medially (Fig. 121). Ninth sternite (Figs 122-123) typical for the subfamily; tenth tergite (Fig. 122) very small, basally inwardly arcuate. Spiculum gastrale (Figs 124-125) dilated on both ends, its body otherwise parallel-sided; basal end spatula-like. Aedeagus (Figs 126-127) gradually narrowing apically, parameres fused on their basal two-thirds (roughly); basal piece of aedeagus rather short, its ratio to fused parameres approximately 1:3.