Archaeoglenes fujikawai Yanagi & Akita, 2024

Yanagi, Takeharu & Akita, Katsumi, 2024, Description of a new species of the genus Archaeoglenes Broun, 1893 (Coleoptera, Tenebrionidae, Phrenapatinae) from the Ryukyus, Japan, with ecological insights, Zootaxa 5538 (1), pp. 45-53 : 46-49

Archaeoglenes fujikawai Yanagi & Akita sp. nov.

[Japanese name: Ryukyu-chibi-kokunusuto-modoki]

( Figs 1–4 , 7 , 9–10 )

Archaeoglenes orientalis Sasaji, 1983 : Ueno 1993: 12 (no specimen data, recorded from Okinawa Is.).; Matsumura et al. 2022: 204, Plate 57, Fig. 4 (no specimen data, recorded from Okinawa Is.).

Type materials. Holotype ♂. “ JAPAN: Ryukyus , / Okinawa-jima Is. , / Kunigami-son, / Benoki, 11.II.2019, / Hiroaki Fujikawa leg. // K. AKITA / Collection / KAC 176665 // Holotype / Archaeoglenes / fujikawai / Yanagi & Akita, 2024” ( MIE).

Paratypes: Ryukyus : Amami-ôshima Is. : 1 ♂, 2 ♀♀, Sumiyô-chô, Santarô-tôge , 22.VIII.2018, Naoki Toda leg. ( KAC, NTC) ; 1 ♂, 3 ♀♀, Uken-son, Yuwan , 3.III.2022, Ryo Nakamura leg. ( RNC) . Okinawa-jima Is. : 29 exs. (incl. 13 ♂♂, 7 ♀♀), same data as for the holotype ( KAC, YNG, HFC) ; 85 exs. (incl. 8 ♂♂, 12 ♀♀), Kunigami-son, Benoki , host sampled by Hiroaki Fujikawa on 12.V.2019, breed by Katsumi Akita, emerg. on 19.III.2020 ( KMC-NSMT, EUM, MIE, NHM, KAC, YNG, HFC) ; 2 ♂♂, 2 ♀♀, Kunigami-son, Benoki , 10.XI.2018, Hiroaki Fujikawa leg. ( KAC); 43 exs. (incl. 2 ♂♂), ditto, 3. III.2019, Hiroaki Fujikawa leg. ( KAC, YNG, HFC) ; 11 exs., ditto, 290 m, 17.II.2019, Fumitaka Nakano leg. ( FNC); 7 exs., ditto, 28. III.2019, Katsuya Nakano leg. ( KNC) ; 17 exs., Kunigami-son, Sate , 345 m, 23.II.2020, Fumitaka Nakano leg. ( FNC, KAC) .

Description. Male. BL 1.56–1.89 mm (av = 1.69 mm, n = 25, holotype: 1.61 mm). BL/BW 2.31–2.38.

Body rounded oval, color dark brown dorsally, slightly lighter in color ventrally.

Head: transverse, HW/HL 2.20–2.24, HW/PW 0.66–0.74; clypeus with anterior margin distinct, loosely triangular anteriorly projection in dorsal view; frontal-clypeal suture semicircular; frons rather densely punctate, anterior margin weakly concave; gena distinctly trapezoidally inflated, with few punctures, lateral parts flattened basolaterally with very fine punctures; vertex gently and distinctly convex, triangularly protruding anteriorly in dorsal view; compound eye very small, each consisting around 15 facets, segmented on the sides of the head. Antennae moderately, ten segmented; segment I rounded, distinctly articulated at junction with segment II; segment II rather small, ovate; segments III–VIII distinctly shorter and connected; segment IX large, bowl-shaped, transversely; segment X very large, rounded, medially convex; 2–4 white pubescence on segment II; sometimes 1–2 very sparse and feeble pubescence on segments IV, VI and VIII; distinctly densely pubescent on segments IX and X. Mandibles distinctly curved as a whole, bifid at the apex, the internal one and a half longer than the external, with a distinct mortar at the basal. Maxilla relatively solid, both lacinia and galea large and broad and bearing several thick setae; maxillary palpus with terminal segment rounded, slightly longer than other segments; labial palpus slender, the terminal segment conical, distinctly longer than other segments.

Pronotum: transverse, rectangular, PW/PL 1.37–1.42, punctate throughout, anterior margin gently arched and densely covered with fine white hairs like a brush; anterior corners rounded and obtuse; lateral margins with anterior corners appear to be slightly three-dimensional and double-structured, very clearly, becoming thicker toward basally, and gently arched down toward dorsum, uneven punctures densely and continuously to propleuron; lateral part distinctly convex in anterior 1/5, concave with indistinct lateral marginal groove from anterior to apical 1/2, almost flat in basal 1/2, but slightly concave in basal 1/5; medial part strongly convex, with rather sparse punctures, posterior part three-dimensional and steeply concave on both sides; median portion with two symmetrical protrusions toward base, with few punctures; middle of the most posterior margin with four rounded triangular protrusions facing, without punctures; the space between each protrusions rugged black and densely covered with many fine punctures.

Propleuron: anterior margin distinctly black, arcing upward and fused with lateral margin of pronotum about at apical 1/5; anterior margin with shallow anterior groove along anterior margin extending ventrally from fusion.

Prosternum: convex, rather densely, coarsely punctate; anterior margin linear, lacking punctures in band; prosternal process concave and truncate, with indistinct punctures, posterior margin distinctly margined in blackish brown, slightly convex; prosternum-propleuron suture completely absent, with continuous punctures; propleuron densely punctate and slightly convex, ventro-anterior margin with a strongly apically mountain-shaped projecting which is finely punctate.

Scutellum: indistinctly concave.

Elytra: ovate, very strongly convex, with coarse puncture lines, EL/EW 1.36–1.42, maximum width at anterior 1/3; lateral and posterior sides steeply inclined; lateral margin strongly protruding ventrally in anterior 1/3, thick wavy and rugose toward wing tip in posterior 1/4, sparsely covered with very fine pubescence at posterior 1/8; humeri strongly protruding laterally, their inner sides slightly concave; gently curved interiorly, with downward projection just above the first stria, massively fused with third and fifth intervals; apices rounded, peripheral postero-lateral margin outwardly protruding; meeting line fused, coarsely and finely punctate along it; interval I slightly convex, stria I with very fine punctures up to basal 1/2, becoming larger posteriorly; interval II barely raised up to basal 1/2, but slightly convex at posterior; stria II punctures generally of normal; interval III distinctly raised; stria III with coarse and rather large punctures; interval IV slightly concave, with bridge-like raised areas between intervals III and V; stria IV punctures also rather large, interval V strongly convex; stria V punctures large and rough, with some gaps; interval VI horizontal or slightly convex, with bridge-like lateral prominence from basal 1/4 to posterior; stria VI slightly finely punctured anteriorly to basal 1/2; interval VII weakly raised anteriorly from base 2/5, strongly linearly raised posteriorly; stria VII distinctly smaller; interval VIII slightly convex, indistinct anteriorly from the basal 1/4 and absent posteriorly 1/3; stria VIII large and coarse, merging with origin of stria VII at basal 1/5; interval IX very slightly convex, disappears near basal 3/5; stria IX fine, with 8–13 punctures, which begin at basal 1/6 and disappear near basal 1/2, and posterior 5 punctures very small; stria X with row of punctures, treated as lateromarginal puncture row in this study.

Hind wing reduced.

Mesothorax: mesosternum with surface microsculpture, elongated posteriorly in center; mesepisternum arcuate, with surface fine punctures, and one or two large punctures; mesepimeron with surface microsculpture and 2–3 large punctures.

Metathorax: metepisternum, coarse, somewhat irregular with 2–3 large punctures, surface somewhat uneven; metasternum large, rounded, oblong, with large, coarse punctures, medial punctures slightly smaller; metepimeron small, like triangular, with coarse very small punctures.

Abdomen: ventrite I transverse, with single large uneven punctures row along posterior margin, linear fusion of metacoxa with edges of puncture; ventrite II, two rows of punctures, larger anteriorly and smaller posteriorly, space between puncture rows linearly convex; ventrite III, posterior 2/3 clearly convex, with two rows of punctures, large and regular anteriorly, but uneven and small posteriorly; ventrite IV with posterior 3/4 strongly protruding ventrally and anterior 1/4 concave; ventrite V semicircular, convex, with two row of 3–4 punctures on anterior margin, anterior one slightly larger, and posterior one smaller and indistinct, terminal end rather densely punctured with fine punctures.

Legs; slender, slightly short, fine hairs rather dense throughout; shape of each leg generally the same.

Aedeagus ( Fig. 7 ) slender, AL 0.30 mm, AW 0.06 mm, AW/AL 0.19–0.20, Aal/AL 0.54–0.55 [n = 10]; thick and parallel on both sides from apical 1/2, tapering abruptly from apical 1/3, apex slightly pointed.

♂ measurements (n = 25): BL/BW 2.31–2.38 (av = 2.32); HW/HL 2.20–2.24 (av = 2.22); HW/PW 0.66–0.74 (av = 0.68); PW/PL 1.37–1.42 (av = 1.38); EL/EW 1.36–1.42 (av = 1.40); EL/PL 2.25–2.36 (av = 2.33); EW/PW 1.19–1.22 (av = 1.21).

♀ (n = 25) ( Fig. 4 ). Body slightly larger, BL 1.69–2.25 mm (av = 1.84 mm, n = 10), more rounded; pronotum more square-like. In many specimens, anterior corner more strongly protruding laterally and anteriorly, but with wide range of variation; elytra, convexity more weakly, maximum width more posteriorly as in male, about 1/2 of length, more parallel on both sides. Female measurements: BL/EW 2.15–2.25 (av = 2.16); HW/HL 2.01–2.14 (av = 2.09); HW/PW 0.54–0.74 (av = 0.58); PW/PL 1.19–1.37 (av = 1.26); EL/EW 1.34–1.45 (av = 1.39); EL/PL 2.21–2.61 (av = 2.43); EW/PW 1.25–1.29 (av = 1.26).

Remarks. Although this new species is similar to A. orientalis Sasaji, 1983 , it can be clearly distinguished by the following differences: body more slender (male BL/EW 2.17–2.24, av = 2.21 [n = 27]; female BL/EW 1.98–2.16, av = 2.06 [n = 23] in A. orientalis ), distinctly darker and dark brown (light brown or yellowish brown in A. orientalis ); male pronotum narrower and longer (PW/PL 1.56–1.61, av = 1.58; EL/PL 2.09–2.14, av = 2.11 [n = 27] in A. orientalis ); elytra more convex, lateral margins more abruptly directed ventrally; male genitalia clearly slender, AW/AL 0.19–0.20, (AW/AL 0.26–0.29 [n = 10] in A. orientalis , see Fig. 8 ); central neckline reaches the apices in ventral view; terminal sternite more rounded, semicircular. The new species is also cearly distinguishable from other species of Archaeoglenes and Sepilokus by differences in antennae, body shapes and elytral costae, etc.

Distribution. Japan: the Ryukyus, Okinawa-jima Is. and Amami-ôshima Is.

Distributional note. A. orientalis was recorded from Tokara Isls., Nakano-shima Is. by Ueno (1993), but it was not possible to examine specimens and therefore its identification is not sure.

Etymology. The specific name of the present new species is given in honor of Mr. Hiroaki Fujikawa who collected the type specimens.

Figures

FIGURE 9. Ecological photo of A. fujikawai sp. nov., inhabiting Akagarezai.

FIGURE 10. Ecological photo of A. fujikawai sp. nov., inhabiting Akagarezai.

FIGURES 1–6. Archaeoglenes spp. 1–3, Archaeoglenes fujikawai sp. nov.: 1, Holotype of A. fujikawai sp. nov. in dorsal view; 2, ditto, in lateral view; 3, ditto, in ventral view; 4, female paratype in dorsal view; 5, A. orientalis, male, in dorsal view; 6, ditto, female, in dorsal view.

FIGURES 7–8. Aedeagus. 7, A. fujikawai sp. nov.; 8, A. orientalis. Scale: 0.1 mm.