Trachyphloeosoma david Borovec & Anderson, 2022

Borovec, Roman & Anderson, Robert, 2022, Three new species of Trachyphloeosoma Wollaston (Coleoptera: Curculionidae Entiminae) from southeast Asia with the first record of the tribe Trachyphloeini from the Philippines, Zootaxa 5182 (1), pp. 93-100 : 97-98

Trachyphloeosoma david Borovec & Anderson spec. n.

( Figs 2 , 9–12 )

Type locality. China, Fujian, Wuyishan Mts. , SE Tongmu-Guadun .

Type material. Holotype: ♀, ‘ China. Fujian prov., Wuyishan Mts. NNR, 0.5 km SE Tongmu-Guadun, 27°43.981′ N 117°38.375′ E, D. Král & J. Růžička lgt., (W09) 25.v.2018, 1230 m, sift #05, detritus with mycelia, dense short bamboo forest with inter-mixed high evergreen trees’ ( NMPC) . Paratypes: 2 spec., the same data as holotype ( NMPC) ; 1 spec., ‘ China. Fujian prov., Wuyishan Mts. NNR, 4.8 km SW Tongmu-Sangang, Xiaofeng Mt. , 27°42.707′ N 117°39.128′ E, D. Král & J. Růžička lgt., (W14) 27.v.2018, 1150 m, sift #08, detritus under dense shrubs, mixed broad-leaved forest with bamboo’ ( RBSC) ; 2 spec., ‘ China. Fujian prov., Wuyishan Mts. NNR, 4.8 km SW Tongmu-Sangang, Xiaofeng Mt. , 27°42.661′ N 117°39.131′ E, D. Král & J. Růžička lgt., (W13) 27.v.2018, 1170 m, sift #07, mixed broad-leaved forest with bamboo’ (1 spec. NMPC, 1 spec. CMNC) ; 1 spec., the same data, but ‘ 1.vi.2018, sift #15’ ( NMPC) .

Description. Body length: holotype 2.63 mm, paratypes 2.59–3.19 mm. Body ( Fig. 2 ) unicoloured piceous brown, antennal funicles with clubs and tarsi paler, reddish brown. Entire body except frons, antennal funicles with clubs and tarsi covered with a light brown, earth-like encrustation which conceals surface; appressed scales, covering entire body hardly visible through this encrustation. Elytra with one conspicuous, dense row of semi-erect setae on each interval; setae almost as long as width of one interval, narrowly subspatulate, only indistinctly enlarged apicad, widest at tip, distance between two setae about as long as length of one seta. Pronotum with similar setae, half as long as those on elytra, arising from the top of pronotal granules, orientated anteriad; head with rostrum with similar setae, irregularly scattered. Antennal scapes, femora and tibiae with fine, moderately long, erect setae, distinctly prominent from outline of scapes and legs.

Rostrum ( Figs 9, 10 ) moderately short and wide, 1.25–1.36 × as wide as long, widest at base and here 1.15–1.21 × as wide as at apex, evenly tapering apicad with almost straight sides; in profile regularly distinctly vaulted. Epifrons tapered anteriad with weakly concave sides, dorsally flat. Frons very short, wide, smooth, shiny, weakly depressed. Epistome extremely short, separated posteriorly by very slender, arched carina. Antennal sockets in dorsal view visible as almost parallel-sided, moderately wide furrows in apical two thirds of rostrum; in lateral view short, distinctly subtriangular, strikingly enlarged posteriad with dorsal margin slightly curved, directed towards dorsal margin of eye, ventral margin distinctly curved, directed deeply below ventral border of eye. Eyes small, in dorsal view not protruding from outline of head; in lateral view placed about in middle of head. Head in profile behind eyes finely longitudinally striate, striae hardly visible below appressed scales.

Antennae with scapes slightly exceeding anterior margin of pronotum, 1.5–1.6 × as long as funicle, in basal third visibly curved, in apical part subparallel-sided, at apex 0.7 × as wide as club. Funicle 7-segmented; segment 1 1.6–1.8 × as long as wide and 1.8–2.0 × as long as segment 2, segment 2 1.4–1.5 × as long as wide; segments 3–5 1.3 × as wide as long; segment 6 1.4 × as wide as long; segment 7 1.6–1.7 × as wide as long; clubs ovoid, short and large, 1.5–1.6 × as long as wide.

Pronotum ( Fig. 2 ) 1.07–1.12 × as wide as long, widest at anterior third, here distinctly rounded, anteriorly distinctly narrower than posteriorly, with anterior margin distinctly narrower than posterior one; sides in basal two thirds slightly rounded, almost straight. Pronotum roughly, irregularly granulate; in lateral view regularly vaulted; anterior margin directed back beneath and towards coxae.

Scutellum not visible.

Elytra ( Fig. 2 ) oval, 1.34–1.42 × as long as wide, widest at midlength, with regularly rounded sides. Striae conspicuously coarsely punctured, slightly impressed between punctures, distinctly wider than interstriae, separation of punctures shorter than their diameters. Interstriae flat, somewhat smooth. Elytra in lateral view slightly vaulted.

All femora edentate. Protibiae short and robust, 5.29–5.45 × as long as wide at midlength, at apical quarter distinctly curved along interior margin with mesal edge distinctly doubly sinuate, apical portion obliquely subtruncate, with fringe of dense, fine, yellowish setae, shorter in mesal than in lateral part, with long, slender brownish mucro. Tarsi short, segment 2 1.5 × as wide as long; segment 3 1.3 × as wide as long and 1.7–1.8 × as wide as segment 2; onychium 0.6 × as long as segment 3, strikingly widened apicad with very long, strongly divaricate claws, almost as long as onychium.

Abdominal ventrites 1.11–1.18 × as long as wide, sparsely roughly punctate; ventrite 2 at middle about as long as ventrite 1, distinctly longer than ventrites 3 and 4 combined; suture between ventrites 1 and 2 sinuose, others straight. Metaventral process about as wide as transverse diameter of metacoxa.

Male genitalia. Unknown.

Female genitalia. Spermatheca ( Fig. 11 ) U-shaped, cornu slender, evenly tapering apicad; ramus undeveloped; collum subtriangular, slightly longer than wide; corpus elongate; spermathecal duct well sclerotised, conspicuous, distinctly long, many times coiled. Sternite VIII ( Fig. 12 ) with plate elongate rhombic, 1.9–2.0 × as long as wide, with fenestra slender, long, reaching just to base of plate. Gonocoxites of ovipositor very slender, long, basally slightly enlarged, in apical part rod-shaped, bearing slender, long, apical, cylindrical stylus with apical setae.

Etymology. This species is named after the eminent specialist on Scarabaeidae , a good friend and colleague of the first author, Dr. David Král (Charles University, Prague, Czech Republic), one of the collectors of the type material. The specific name is a noun in apposition.

Bionomy. Specimens were sifted from forest detritus under mixed broad-leaved forest mixed with bamboo.

Differential diagnosis. The largest species of the genus, Trachyphloeosoma david is very similar to T. advena Zimmerman, 1956 in having funicles 7-segmented, rostrum widest at base, evenly tapered anteriad with straight sides, eyes large, dorsal margin of antennal sockets directed towards dorsal margin of eye, pronotum slender, all elytral interstriae with long, slender, erect setae, short onychium and female sternite VIII with arms defining slender fenestra. In the last key for that genus ( Borovec 2021) T. david belongs to the point 10. It is possible to distinguish it from T. advena by the following set of characters:

T. david: Larger , 2.6–3.2 mm. Elytral semi-erect setae narrowly subspatulate, slightly enlarged apicad. Pronotal setae semi-erect, inconspicuous, about half as long as those of elytra. Rostrum longer, 1.25–1.36 × as wide as long ( Fig. 9 ). Pronotum more slender, 1.07–1.12 × as wide as long. Elytra longer, 1.34–1.42 × as long as wide. Plate of female sternite VIII long, 1.9–2.0 × as long as wide, with fenestra long, reaching base of plate ( Fig. 12 ). Spermathecal duct well sclerotised, conspicuous, distinctly long and many times coiled ( Fig. 11 ).

T. advena: Smaller , 2.0– 2.3 mm. Elytral setae erect, piliform. Pronotal setae erect, conspicuous, almost as long as those of elytra. Rostrum shorter, 1.35–1.44 × as wide as long ( Fig. 13 ). Pronotum wider, 1.11–1.20 × as wide as long. Elytra shorter, 1.26–1.31 × longer than wide. Plate of female sternite VIII short, 1.5–1.6 × as long as wide, with fenestra long, reaching base of plate ( Fig. 16 ). Spermathecal duct unsclerotised, not visible, short ( Fig. 15 ).

Trachyphloeosoma david is also similar to T. ales , but it can be easily distinguished by the following set of characters: pronotum regularly domed (vs. with longitudinal median furrow in T. ales ), abdominal ventrites sparsely punctate (vs. densely punctate) and spermatheca with collum subtriangular and spermathecal duct conspicuous, well sclerotised (vs. spermatheca with corpus apically regularly rounded and spermathecal duct translucent, not visible).

Figures

FIGURES 1–3. Dorsal habitus. 1. Trachyphloeosoma ales. 2. T. david. 3. T. philippinense. Not to scale.

FIGURES 4–26. Structural details. 4–8. Trachyphloeosoma ales. 4. Head and rostrum, dorsal view. 5. Head and rostrum, lateral view. 6. Penis, dorsal and lateral view. 7. Spermatheca. 8. Sternite VIII in female. 9–12. T. david. 9. Head and rostrum, dorsal view. 10. Head and rostrum, lateral view. 11. Spermatheca. 12. Sternite VIII in female. 13–16. T. advena. 13. Head and rostrum, dorsal view. 14. Head and rostrum, lateral view. 15. Spermatheca. 16. Sternite VIII in female. 17–21. T. philippinense. 17. Head and rostrum, dorsal view. 18. Head and rostrum, lateral view. 19. Penis, dorsal and lateral view. 20. Spermatheca. 21. Sternite VIII in female. 22–26. T. buruana. 22. Head and rostrum, dorsal view. 23. Head and rostrum, lateral view. 24. Penis, dorsal and lateral view. 25. Spermatheca. 26. Sternite VIII in female. Scale bars: 0.50 mm (4, 5, 8–10, 12–14, 16–18, 21–23, 26), and 0.25 mm (6, 7, 11, 15, 19, 20, 24, 25).