Apetasimus involucer Scott

Ewing, Curtis, 2006, Revision of the endemic Hawaiian sap beetle genus Apetasimus Sharp 1908 (Coleoptera: Nitidulidae), Zootaxa 1385, pp. 1-30 : 16-18

publication ID	https://doi.org/ 10.5281/zenodo.175088
DOI	https://doi.org/10.5281/zenodo.6254938
persistent identifier	https://treatment.plazi.org/id/464B425A-FF90-2452-FE93-FA8F1763FC23
treatment provided by	Plazi
scientific name	Apetasimus involucer Scott
status

Treatment

Apetasimus involucer Scott in Sharp & Scott, 1908: 458.

Diagnosis:

The only nitidulid on Kauai with reduced flight wings. It can be separated from other involucer -group members by the combination of less reduced eyes ( Fig. 2 View FIGURE 2 L) and tarsal lobes ( Fig. 2 View FIGURE 2 J), and from the brachypterous Eupetinus by prosternal process strongly recurved dorsad behind procoxae.

Description

Size: Length 4.8mm, Width 2.0– 2.1mm

Color: brick red

Head: ( Fig. 2 View FIGURE 2 L) Transverse, 0.76mm L, 1.02mm W, L/W ratio 0.75. Punctures dense and definite, some irregularly shaped due to contiguous adjacent punctures, intervals glabrous to reticulate. Eyes medium, length 0.20mm, facets 12, medial margin arcuate.

Temple long, rounded, postgenae shallowly concave. Antennomere 5 elongate, 6 quadrate, 7 and 8 transverse.

Prothorax: Pronotum transverse, 1.16mm L, 1.81mm W, L/W ratio 0.64 ( Fig. 2 View FIGURE 2 K). Lateral margins broadly rounded, slightly recurved at posterior angle, narrowed anterad, widest near midpoint, anterior/posterior width ratio 0.64. Distinctly emarginate anteriorly, posterior margin truncate medially, inflexed laterally, bead distinct laterally, obsolete beyond anterior angle, along posterior margin most distinct medially. Punctation coarse, definite, dense, granular microsculpture inside punctures, intervals glabrous with some fine radiating lines. Prosternal process short, narrow between procoxae, expanded apically ( Fig. 4 View FIGURE 4 C), meeting mesosternum at ~45° angle, apex with long fimbria ( Fig. 4 View FIGURE 4 D).

Elytra: ( Fig. 2 View FIGURE 2 E) 1.52mm L, 0.98mm W, L/W ratio1.55. Interstitial setae forming tufts on dilated areas at base and apex of 3rd, 5th, and 9th interstices, and at midpoint and apex of 7th. Lateral edge smoothly curved in anterior 1/2, straighter and attenuated in posterior 1/2, widest 1/3 of total length from humeri, narrowest at posterior margin. Lateral margin strongly explanate anterad (0.22 of total at widest point), becoming less explanate toward posterior margin, obsolete just before posterior margin. Posterior margin subtruncate, broadly rounded.

Legs: Tarsomeres 1 and 2 with small lobes, tarsomere 3 lobe narrow, elongate, projecting to distal margin of 4 ( Fig. 2 View FIGURE 2 J).

Abdomen: Tergite 5, 6, and pygidium with nearly obsolete granular microsculpture, progressively more defined apically. Punctation definite, separated by 1–2 diameters. Male; pygidium gradually tapered, narrow, apex with notch, lateral apices acuminate, tip rounded and slightly upturned ( Fig. 2 View FIGURE 2 H), apex of sternite 7 bisinuate, fimbria short ( Fig. 2 View FIGURE 2 I). Female; pygidium elongate, projecting beyond posterior margin of sternite 7, posterior margin truncate, rounded laterally, with shallow medial depression at posterior margin creating appearance of emargination when viewed from angle, fimbria longest medially, length evenly decreased to lateral margin ( Fig. 2 View FIGURE 2 F). Apex of sternite 7 short, subtruncate ( Fig. 2 View FIGURE 2 G).

Male genitalia: Tergite 8 with shallow median notch, broadly rounded laterally, fimbria evenly arranged on serrate lateral lobes, median notch smooth with 3 setae on midline ( Fig. 2 View FIGURE 2 N). Posterior margin of sternite 8 smoothly concave with small median protuberance, 4 to 5 macrosetae and one microseta on each side of concavity ( Fig. 2 View FIGURE 2 N). Tegmen broadly rounded with small apico-medial protuberance, lateral setae extend from edge of protuberance to point even with anterior excavation. Posterior excavation with setae laterally for 3/4 length, lip of anterior excavation spiculate, median triangle of longer setae at base of lip ( Fig. 2 View FIGURE 2 M). Aedeagus concave ventrally, tip acuminate in lateral view ( Fig. 2 View FIGURE 2 D), nearly parallel in ventral view, widest at base of apex, apex acuminate, tip blunt ( Fig. 2 View FIGURE 2 C). Basisac covered with short triangular spicules, two longitudinal folds extend from base of aedeagus to 7/8 length on dorsal surface. Distal 1/3 of manicasac spiculate. Sclerites-primary of perisac dorsal, heavily sclerotized, distal apices forming small ventrally directed hooks. Flagellum fused to proximal end of sclerites-primary, directed ventrally proximad junction with sperm duct. Dorsal emargination deep, 2/3 length, ventral emargination shallow, 1/6 length. Spicules extend from behind apex of flagellum to midlength on ventral surface, extended laterally ( Figs. 2 View FIGURE 2 A, 2B).

Female genitalia: Gonocoxites elongate, rounded at apex forming apical median notch. Lateral groove short, 0.28 x length of gonocoxite, 3 prestylar setae, stylus subapical, subequal to stylus length from tip, 2 apical stylar setae ( Fig. 3 View FIGURE 3 C). Vagina with U-shaped pouch at junction of bursa copulatrix. Base of bursa copulatrix constricted, evenly expanded to 90° bend near spermathecal duct, small patch of spicules at bend ( Fig. 3 View FIGURE 3 A). Spermatheca with apical depression funnel shaped, rounded at apex. Base of gland with U-shaped bend at insertion point ( Fig. 3 View FIGURE 3 B).

Lectotype ɗ, glued to card labeled: "Kauai, Makeweli, 2,500ft., II. 1897. Perkins, ɗ Type H.S.", underside of card "703" / " Type H.T." / "Sandwich Is., 1912–215". (BMNH).

Paralectotypes: 3 Ψ, 2 ɗ (BPBM). 2 Ψ, 1 ɗ (BMNH).

Etymology: (L.) involucrum; wrapper, case, envelope.

Distribution: Makaweli, Kauai, 2,500 ft.

Habits: Unknown.

Kingdom	Animalia
Phylum	Arthropoda
Class	Insecta
Order	Coleoptera
Family	Nitidulidae
Genus	Apetasimus