Trachystolodes tianjialini, Wang & Xie & Wang, 2021

Wang, Yu, Xie, Guanglin & Wang, Wenkai, 2021, A new species of Trachystolodes Breuning, 1943 from Central China (Coleoptera Cerambycidae, Lamiinae), Zootaxa 4942 (1), pp. 135-140 : 137-140

Trachystolodes tianjialini sp. nov. (mẋṚDR+)

( Figs 1, 4 , 7 , 10, 13, 16–25 )

Description. Male (holotype): Length 19.5 mm (measured from vertex to elytral apices), width 8.4 mm (measured across humeri). Body black, mostly clothed with brown to castaneous appressed pubescence, with sparse grey-white appressed setae. Labrum and lower edge of frons covered with long gold setae ( Fig 13 ); frons with some short erect black setae laterally; pronotum with short gold setae on anterior and posterior margin ( Fig 10 ), and with several long brown setae on both sides behind the middle of disc. Elytra slightly darker at middle, each elytron with a black oblique patch of short setae behind the middle, and unevenly spaced with black and white short setae presenting inconspicuous spots on posterior third, black setae extend forward along the suture to anterior fourth.

Head sparsely and shallowly punctate; frons transverse, slightly convex, with fine punctation, vertex coarsely wrinkled between eyes. Antennae about 1.5 times as long as body, scape cylindrical, about as long as antennomere III, antennomeres III–X gradually decreasing in length; antennomere XI subequal in length to antennomere IV. Pronotum broader than long, width (across tips of lateral spines) about 1.6 times as long as length; lateral spine short, with basal half thickened and apical half tapered; disc with three distinct small calli, two laterals located before middle, relatively smaller, subuliform, and one central, close to posterior margin, subtriangular, with a mesial longitudinal furrow, strongly notched apically ( Fig 10 ). Scutellum linguiform. Elytra elongate, about 1.5 times as long as humeral width; subparallel at middle, then gradually narrowing towards apex, rounded apically; elytral surface strongly punctate, with glabrous granules of different size before black patches, and with basal longitudinal ridges of granules ( Figs 7 , 10 ). Distal abdominal sternite with apical edge nearly straight. Legs moderately long; claws widely divergent.

Male genitalia: Tergite VIII ( Fig 21 ) mostly yellowish-brown, with fuscous to black brown edge and a triangular apical pigmented patch, apex broadly truncate, slightly emarginate medially, dorsal surface on apical third and apical two-thirds on lateral margins with sparse long setae. Sternite VIII ( Fig 22 ) with an umbrella-shaped pigmented patch and a stout spiculum relictum. Spiculum gastrale ( Figs 23–25 ) curved in lateral view, broadly bifurcate basally. Parameres black brown, inner sides subparallel, with setae of various lengths apically. Tegminal struts of phallobase separated apically. Penis uniformly curved, dorsal struts about 0.48 time as long as whole penis ( Figs 18–20 ).

Female: No specimens available for study, but two photographs of a specimen ( Figs 16–17 ) may represent its habitus.

Remarks. Breuning (1943) described a variation of T. tonkinensis as “m. pici” based on a specimen with the pronotum with less acute lateral spines and more parallel lateral margins, the elytra with smaller basal granules, less developed basal ridge and the slightly smaller posterior spots without ocherous bordering.

The new species is very similar with T. tonkinensis , mainly with the variation described by Breuning as m. pici, but it can be distinguished from it by the femora without golden apical rings and the tibiae without golden basal spots on dorsum ( Figs 1, 4 , 7 ), the frons with sparser, finer and shallower punctations ( Fig 13 ), the male antennae about 1.5 times as long as body, with distal three antennomeres exceeding elytral apex (while in T. tonkinensis , the male antennae is about 2.0 times, with distal five to six antennomeres exceeding elytral apex), and the elytra with indistinctly longitudinal basal ridges and the smaller posterior spots ( Figs 1–2 ). Some characters of the genitalia also allow to differentiate both species: in the new species the apical margin of tergite VIII is broadly truncate and emarginate medially, and the apex of parameres is close to each other ( Figs 18, 21 ). In T. tonkinensis the apical margin of tergite VIII is rounded, the apex of parameres is relatively wide apart from each other. Illustrations of the male terminalia of T. tonkinensis refer to Huang et al. (2020).

The new species shares with T. huangjianbini the femora without golden rings at apex and tibiae without golden spots, and the elytral spots without ocherous bordering ( Figs 1, 3–4, 6–7, 9 ). The new species differs by the different pronotal calli ( Figs 10, 12 ), the frontal punctations ( Figs 13, 15 ), the elytral basal ridges and posterior spot shape ( Figs 1, 3 , 7, 9 ), the apical margin of tergite VIII emarginate, and the apex of parameres close to each other ( Figs 18, 21 ). In T. huangjianbini , the apical margin of tergite VIII is truncate and straight and the apex of parameres are away from each other. Illustrations of the male terminalia of T. huangjianbini refer to Huang et al. (2020).

It is worth mentioning that T. huangjianbini has the notably different pronotal calli which are rather large, nearly rectangular, flat, and strongly wrinkled dorsally, while in the other species of the genus, the pronotal calli are relatively small, away from each other, the two anterior laterals are distinctly subuliform and the posteromedial is subtriangular.

Another specimen (may be a female, according to the length of antenna, which is subequal to the body and is showed in Figs 16–17 ) of the new species was found by Mr. Zheyu Chen in Chaibuxi Canyon in the same county on June 26, 2019, about 60 km away from the type locality as the crow flies. Unfortunately, the specimen has been lost and only two photographs have been kept ( Figs 16–17 ).

Type material examined. Holotype (male), China: Hubei, Wufeng county, Houhe National Nature Reserve , August 2, 2019, coll. by Shuai Zhao. The holotype is deposited in the Entomological Museum, Yangtze University, Jingzhou, China.

Distribution. China: Hubei (Wufeng).

Etymology. This new species is named after Mr. Jialin Tian, to appreciating his help in the specimen collection.

Figures

FIGURES 1–6. Male habitus of Trachystolodes spp. 1, 4. T. tianjialini sp. nov., holotype; 2, 5. T. tonkinensis; 3, 6. T. huangjianbini, holotype. 1–3. Dorsal view; 4–6. Ventral view. 2, 3, 5, 6 taken by Guiqiang Huang.

FIGURES 7–9. Male habitus of Trachystolodes spp., lateral view. 7. T. tianjialini sp. nov., holotype; 8. T. tonkinensis; 9. T. huangjianbini, holotype. 8, 9 taken by Guiqiang Huang.

FIGURES 10–17. Habitus of Trachystolodes spp. 10, 13, 16–17. T. tianjialini sp. nov., 10, 13. holotype; 11, 14. T. tonkinensis; 12, 15. T. huangjianbini, holotype. 10–12. Dorsal view of pronotum and base of elytra; 13–15. Frontal view of head; 16–17. Living adult (maybe a female). 11–12, 14–15 taken by Guiqiang Huang; 16–17 taken by Zheyu Chen.

FIGURES 18–25. Male terminalia of T. tianjialini sp. nov., holotype. 18–20. Tegmen + aedeagus. 21–22. Tergite VIII and sternite VIII; 23–25. Spiculum gastrale; 18, 21, 23. Dorsal view; 19, 24. Lateral view; 20, 22, 25. Ventral view. Scale bar: 1.0 mm.