Wagnerinus frugivorus Yoshitake

Yoshitake, Hiraku, Kato, Toshihide, Jinbo, Utsugi & Ito, Motomi, 2008, A new Wagnerinus (Coleoptera: Curculionidae) from northern Japan: Description including a DNA barcode, Zootaxa 1740, pp. 15-27 : 17-23

Wagnerinus frugivorus Yoshitake , sp. nov.

( Figs. 2–28 )

Diagnosis. This species is distinguished from other congeners mainly by the following characteristics in males: mucrones of mid and hind tibiae larger, more acute ( Figs. 12, 13 ); concavity on ventrites I and II deeper ( Fig. 14 ); paired prominences on ventrite V larger ( Figs. 15, 16 ).

Description. Male. LB: 2.25–2.68 (mean 2.48). LR: 1.11–1.36 (mean 1.23). WP: 0.81–1.00 (mean 0.91). LP: 0.63–0.76 (mean 0.70). WE: 1.40–1.69 (mean 1.56). LE: 1.68–2.03 (mean 1.86). N = 5 for all measurements. Habitus as shown in Figs. 2 and 3 .

Black in general appearance; apex of rostrum, antennae, and legs tinged with red.

Body surface very shiny, but evenly covered with ochraceous secretions in life ( Fig. 26 ). Head moderately covered with dark hair-like scales; scales becoming paler on frons. Rostrum moderately covered with dark hair-like scales at base; scales becoming sparser and minute apically. Prothorax moderately covered with dark hair-like scales, mingled with light-colored scales; dorsum with 3 stripes of white elliptic to lanceolate scales; basal margin fringed with row of minute ovate scales; latero-ventral parts with stripes of white elliptic to lanceolate scales; ocular lobes fringed with short vibrissae. Elytra sparsely covered with dark hair-like scales; interval I with longitudinal postscutellar patch of dense elliptic to lanceolate white scales. Legs moderately covered with white hair-like to linear scales; scales replaced with brown setae in apical part of each tibia. Lateral pieces of meso- and metasterna sparsely covered with white elliptic to lanceolate scales, except upper part of mesepimera and posterior part of metepisterna densely covered with white lanceolate scales. Sterna moderately covered with light-colored elliptic to lanceolate scales, sparsely mingled with hairs and linear scales; scales becoming sparser on the periphery. Venter moderately covered with elliptic to lanceolate white scales, sparsely mingled with hairs and linear scales; scales becoming sparser on the periphery; ventrites III and IV with scales in line on disc; ventrite V covered with dark hairs and white linear scales on prominences; posterior margins of prominences fringed with dense white acicular to lanceolate scales. Tergite VIII mostly covered with dark fine incurved hairs, mingled with white linear scales.

Head ( Figs. 4, 5 ) finely reticulately punctured, with long glossy median carina extending from vertex to base of forehead; forehead faintly depressed, slightly wider than base of rostrum. Eyes ( Figs. 4, 5 ) moderately prominent from outline of head, not approximated anteriorly. Rostrum ( Figs. 4, 5 ) slender, 1.70–1.79 times as long as prothorax, evenly moderately curved; dorsum with 3 glossy carinae extending from base to middle, minutely punctured along carinae, and shallowly emarginate at apex; punctures becoming minute and sparser apically; sides slightly dilated from constricted base, subparallel in basal 1/3, slightly dilated to antennal insertions, subparallel to apical 1/4, then gradually expanded toward apex; antennal scrobes well-separated along entire length. Antennae ( Figs. 6, 7 ) inserted at middle of rostrum; scape moderate in length, nearly as long as funicular segments I, II, III, IV, and V combined, bluntly produced into short lamina at apex; funicle 7-segmented, with segment I as long as II, II nearly twice as long as III, III nearly as long as IV, IV slightly longer than V, V as long as VI, VI as long as VII, and VII evidently longer than wide; club lanceolate, finely pubescent except basal 1/4.

Prothorax ( Figs. 8, 9 ) 1.28–1.33 times as wide as long, closely punctured; dorsum densely finely punctured along midline; apical margin slightly anteriorly produced, widely shallowly emarginated in middle, nearly flat in profile; basal margin bisinuate, nearly flat, not raised to basal margin of elytra, smooth, not crenulate; sides slightly dilated from constricted base, widest at basal 1/3, slightly narrowed to apical 1/3, then rapidly convergent toward subapical constriction.

Elytra ( Fig. 10 ) 1.18–1.21 times as long as wide, very shiny, widest just behind humeri, subparallel-sided in basal half, then gently convergent toward subapical calli; suture nearly straight; each interval with 1–2 rows of small squamate granules; odd-numbered intervals more prominent than even-numbered ones; striae shallow; each puncture in striae oval, bearing minute hair, flanked by granules, separated by distance greater than its diameter; basal margin fringed with row of minute hairs.

Legs relatively slender; femora clavate, toothed; each tooth small, obtuse, concealed by bundle of suberect white scales; hind femora simple, lacking jumping organ; tibiae ( Figs. 11–13 ) mucronate on mid and hind legs; each mucro acute, conspicuous; tarsi simple, bearing no projection; claws without setae, appendiculate; appendages large, acute.

Sterna moderately punctured; prosternum densely punctured in intercoxal area, with deep rostral groove before coxae; groove limited laterally by keels; mesosternum densely punctured in anterior part, with shallow circular depression in middle for reception of rostrum; metasternum coarsely punctured on sides, with shallow longitudinal depression in middle for reception of rostrum. Venter ( Figs. 14, 15 ) moderately punctured, opaque; ventrite I widely concave on disc, with strong luster in concavity; ventrite II narrowly concave in middle; ventrites III and IV with punctures in line; ventrite V with large semicircular concavity on disc; concavity deep, finely punctured, bearing large acute prominence on each side. Tergite VII with pair of minute plectral tubercles; each tubercle bearing hair. Pygidium ( Fig. 16 ) transverse-pentagonal, nearly twice as wide as long, opaque, densely punctured; upper flange smooth, lacking projection, arcuate downward on each side. Sternite IX ( Fig. 19 ) diminished to pair of small oblong-ovate sclerites; spiculum gastrale ( Fig. 19 ) slightly longer than aedeagal body, nearly as long as aedeagal apodemes, faintly curved leftward. Tegmen ( Fig. 20 ) with slender apodeme; apodeme slightly longer than diameter of tegminal ring. Aedeagal body ( Figs. 17, 18 ) slender, weakly curved, with blunt apical projection on ventral side; sides moderately expanded from base, slightly constricted at basal 1/4, gently narrowed to apical 1/4, then straightly narrowed to subapical part, and finally more strongly straightly convergent to apex; apodeme slender, nearly as long as body. Endophallus ( Fig. 17 ) moderate in length, slightly longer than aedeagal body, with 2 plate-like sclerites at base, with 4 longitudinal rows of dentiform sclerites in middle; plate-like sclerites followed by obtuse triangular spicules; rows of dentiform sclerites followed by acicular spicules; triangular spicules dense, forming spiculate field in basal part; acicular spicules rather sparse, forming indistinct spiculate field in subapical part.

Female. LB: 2.35–2.68 (mean 2.57). LR: 1.15–1.33 (mean 1.28). WP: 0.88–0.99 (mean 0.95). LP: 0.65– 0.75 (mean 0.72). WE: 1.49–1.68 (mean 1.62). LE: 1.80–2.00 (mean 1.93). N = 5 for all measurements.

Rostrum 1.74–1.79 times as long as prothorax, slightly thinner, polished in apical half. Antennae inserted just behind middle of rostrum. Prothorax 1.30–1.35 times as wide as long. Elytra 1.18–1.21 times as long as wide. All tibiae simple, not mucronate. Ventrite I faintly narrowly concave in middle. Ventrite II simple, lacking concavity. Ventrite V slightly inflated on disc. Pygidium smaller, narrower, fan-shaped. Sternite VIII ( Fig. 21 ) with slender arms nearly as long as apodemes, apically furnished with pair of patches of several long setae; apodemes moderate in length. Ovipositor ( Fig. 22 ) with coxites robust, nearly half as long as plate of sternite VIII, nearly twice as long as styli, partially sclerotized, furnished with several minute setae; each coxite followed by plate-like sclerite; styli cylindrical, nearly three times as long as broad, inserted apicolaterally, apically furnished with several short setae. Spermatheca ( Fig. 23 ) larger than apex of ovipositor; cornu long, attenuate, with small projection at apex; collum moderately developed; ramus indistinct, almost uniformly continuous with body; gland short, slightly longer than body; insertions of duct and gland close to each another. Otherwise, essentially as in males.

DNA barcode. A 1366-bp fragment of the COI gene from the holotype was determined. The sequence data including the standard barcoding region for animal species has been deposited as a DNA barcode of W. frugivorus in the DDBJ Nucleotide Sequence Database under accession number AB 250208 .

Type series. HOLOTYPE male (Type No. 3238, Voucher No. 0 0 0 0 0 0 0 1, ELKU), “[ JAPAN: Hokkaido] Kamikawa / Aizankei (930–1,035 m) / N 43°43’28.4”E 142°48’32.4”– / N 43°42’51.2”E 142°48’15.8” / 5. VII. 2005 Hiraku Yoshitake” (typed on a white card), “On Weigela middendorffiana / (Carr.) K. Koch / Caprifoliaceae ) / [JN: Ukon-utsugi] / Det. Motomi Ito, 2005” (typed on a white card), “male” (typed on white card), “Right legs away / for DNA extraction” (typed on a yellow card), “[HOLOTYPE] / Wagnerinus frugivorus / Yoshitake, 2006 ” (typed on a red card); “ ELKU Voucher Specimen / No. 00000001” (typed on a red card). PARATYPES (46 males and 35 females). JAPAN: HOKKAIDO. Aizankei, Kamikawa: 17 males and 10 females, same data as for the holotype ( PCHY); 2 males and 2 females, 2. vii. 1982, Y. Sawada, on W. middendorffiana . Yukomanbetsu, Higashikawa ( MNHAH): 22 males and 19 females, 1035–1100 m, 6. vii. 2005, H. Yoshitake, on W. middendorffiana ( PCHY); 1 female, 1000 m, 6–8. vii. 1980, H. Takemoto ( ELKU). 5 males and 3 females, Horoshikatouge Pass, 1050–1085 m, Kamishihoro, 7. vii. 2005, H. Yoshitake, on W. middendorffiana ( PCHY).

Distribution. The type series were collected from mountainous areas (930–1100 m) in Daisetsuzan National Park, which is located in the center of Hokkaido, northern Japan ( Fig. 1).

Natural history. This species is associated with Weigela middendorffiana (Caprifoliaceae) ( Fig. 24 ). The host plant is a deciduous shrub distributed in Sakhalin, the Kuriles, Hokkaido, northern Honshu, Ussuri, Amur, and Okhotsk, and in subalpine scrub and on exposed slopes ( Ohba 1993). In all study sites, many adults were found on W. middendorffiana growing along margins of subalpine forests dominated by Picea jezoensis (Pinaceae) , Picea glehnii (Pinaceae) , and Betula ermanii (Betulaceae) ( Figs. 25, 26 ). They were diurnal and were observed feeding on flowers and leaves of W. middendorffiana . Female adults laid their eggs singly in the unripe seed capsules of W. middendorffiana . Hatched larvae grew in and fed on the capsules ( Fig. 27 ) and pupated in the soil when they fully matured ( Fig. 28 ). About one month elapsed between hatching and emergence. The voltinism of W. frugivorus is not clear at this time, although this species may be univoltine, as are most other ceutorhynchine weevils from temperate regions.

Etymology. This species was named after its larval feeding habit.

Figures

FIGURES 2, 3. Wagnerinus frugivorus Yoshitake. 2. Dorsal habitus. 3. Lateral habitus.

FIGURES 4 – 10. Wagnerinus frugivorus Yoshitake. 4. Dorsal view of head, male. 5. Lateral view of head, male. 6. Antennal space. 7. Antennal funicle. 8. Dorsal view of prothorax. 9. Lateral view of prothorax. 10. Elytron. Scale: 0.50 mm for 4, 5, 8, 9; 0.20 mm for 6, 7; 1.00 mm for 10.

FIGURES 11 – 16. Wagnerinus frugivorus Yoshitake. 11. Front tibia, male. 12. Mid tibia, male. 13. Hind tibia, male. 14. Venter, male. 15. Ventrites III – V, male. 16. Pygidium, male. Scale: 0.20 mm for 11 – 13; 0.50 mm for 14, 15; 0.25 mm for 16.

FIGURES 17 – 23. Wagnerinus frugivorus Yoshitake. 17 – 20. Male genitalia. 17. Dorsal view of aedeagus. 18. Lateral view of aedeagus. 19. Sternite IX. 20. Tegmen. 21 – 23. Female genitalia. 21. Sternite VIII. 22. Ovipositor. 23. Spermatheca. Scale: 0.20 mm for 17 – 20; 0.10 mm for 21 – 23.

FIGURES 24 – 28. Wagnerinus frugivorus Yoshitake. 24. Host plant, Weigela middendorffiana. 25. Habitat in Aizankei, Kamikawa, Hokkaido. 26. Adult on a leaf of W. middendorffiana. 27. Third-instar larva in a seed capsule of W. middendorffiana. 28. Pupa in the soil.