Apetasimus abstrusus Ewing, sp. nov.
Creators: name: Ewing, Curtis
Publisher: name: Zenodo
Year: 2006
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Nitidulidae
Apetasimus
Apetasimus abstrusus

description: Apetasimus abstrusus Ewing sp. nov.
Diagnosis
Distinguishable from brachypterous Eupetinus and Gonioryctus by reduced eyes and tarsal lobes, more rounded temples and convex pronotum. Closely resembles A. conditus from Molokai but separated by shallow pronotal punctures, appearing irregular with intervals granular and prosternal process meeting postcoxal sclerites at 45° angle vs. 60° angle for A. ganeademus. (Fig. 4 D).
Description
Size: Length 4.7mm, Width 2.1mm
Color: head and elytra orange-red, remainder pale yellow
Head: Transverse (Fig. 4 B), 0.72mm L, 0.96mm W, L/W ratio 0.75. Punctation shallow, dense, adjacent punctures often contiguous, interval microsculpture on clypeus granular, elsewhere linear. Eye reduced, length 0.07mm, facets 6, anterior medial margin convergent. Temple distinct, forming obtuse angle with convex postgena. Antennomeres 1–4 elongate, 5 quadrate, 6–8 transverse.
Prothorax: Pronotum transverse, 1.09mm L, 1.74 W, L/W ratio 0.63 (Fig. 4 E). Lateral margin weakly explanate in anterior 1/2, with even increase in width to strongly explanate posterior angle. Lateral margin broadly rounded, widest behind midpoint, slightly sinuate before hind angle, hind angle definite, nearly at a right angle. Anterior margin distinctly narrower than posterior margin, anterior/posterior width ratio 0.62. Distinctly emarginate anteriorly, angles rounded. Posterior margin shallowly bisinuate. Bead definite from inside anterior angle to posterior angle, obsolete at posterior margin of angle, defined by fine line posterio-medially. Punctation of disc shallow, dense, becoming less definite laterally, indistinct at margin and appearing roughened, intervals granular. Prosternal process short, narrow between coxae, expanded apically (Fig. 4 C), strongly recurved dorsad behind coxae, meeting mesosternum at approximately 45° angle, apex fimbriate (Fig. 4 C).
Elytra: 1.74mm L, 1.21mm W, L/W ratio 1.44 (Fig. 4 A). Surface uneven, striae shallow, slightly irregular, striae wider than interstices. Striae consisting of dense, irregular punctures, appearing unevenly granular, interstices crossed by numerous irregular lines. Lateral margin evenly curved, abruptly and widely explanate behind humeri, narrowed evenly to posterior angle. Posterior margin shallowly bisinuate.
Legs: Lobes of pro- and mesotarsomeres 1 and 2 obsolete, 3 extended 1/2 length of tarsomere 4. Metatarsomeres 1–3 with lobes obsolete (Fig. 4 F).
Abdomen: Male; surface of tergite 5, 6, and pygidium with granular microsculpture, punctures distinct medially, dense and irregular laterally. Female; pygidium with punctation large anteromedially, progressively finer and less distinct toward apex, shallow medial depression at posterior margin appearing emarginate when viewed from angle. Apex of pygidium rounded, fimbria short (Fig. 2 F). Apex of sternite 7 broadly rounded, fimbria short (Fig. 2 G).
Holotype Ψ, labeled: "Oahu, Waianae Mts., Mt. Kaala NAR, 18–V–1991, el. 1,210m., Sifting tree fern litter beside road, J. K. Liebherr coll." (CUIC).
Etymology: (L.) abstrusus; hidden, concealed.
Distribution: Known from type locality.
Habits: Apparently rare, although the holotype was collected in tree fern litter it is possible that it is common in a different habitat. Mt. Kaala is one of the most intensively collected native dominated forest habitats in Hawaii, and other species of endemic nitidulid (i.e. Eupetinus) have been repeatedly collected in litter there.
description: Published as part of Ewing, Curtis, 2006, Revision of the endemic Hawaiian sap beetle genus Apetasimus Sharp 1908 (Coleoptera: Nitidulidae), pp. 1-30 in Zootaxa 1385 on pages 18-19, DOI: 10.5281/zenodo.175088