Crossotarsus beaveri Lai & Wang, 2021

Lai, Shengchang, Zhang, Ling, Li, You & Wang, Jianguo, 2021, A new species, a new combination, and a new record of Crossotarsus Chapuis, 1865 (Coleoptera, Curculionidae, Platypodinae) from China, ZooKeys 1028, pp. 69-83 : 69

Crossotarsus beaveri Lai & Wang sp. nov. Figures 1 , 2

Type material.

Holotype. Male, China: Jiangxi Province, Ganzhou City, Longnan County, Jiulianshan national nature reserve of Jiangxi, Hualu Village, 24°37'19"N, 114°29'57"E, 2.VII.2020, log dissection, host Paulownia fortunei , Shengchang Lai leg. (deposited in NZMC IOZ(E)225775).

Allotype. Female, same data as holotype (deposited in NZMC IOZ(E)225776).

Paratypes. 6 males, 6 females, same data as holotype, but host Phoebe zhennan and Liquidambar formosana (5 males, 5 females JXAU; 1 male, 1 female NZMC); 11 male, 6 females, as holotype except: Xunwu County, Xiangshan Town, Congkeng Village, 24°54'20"N, 115°52'44"E, ca 650m, 15.IX.2017, log dissection, host Castanopsis fargesii and Vernicia montana , Shengchang Lai leg. (10 males, 5 females JXAU; 1 male, 1 female RAB); 6 males, 6 females, as holotype except: Xunwu County, Liuche Town, Luanluozhang, 24°40'41"N, 115°44'9"E, ca 640 m, 22.VIII.2017, log dissection, host Castanopsis carlesii , Shengchang Lai leg. (5 males, 5 females JXAU; 1 male, 1 female RAB); 38 males, 38 females, China: Fujian Province, Zhangzhou City, Yunxiao County, Xiahe Town, Qigaoqi Village, 24°1'31"N, 117°10'36"E, 8.VII.2019, log dissection, host C. carlesii , Ling Zhang leg. (2 males, 2 females BMNH; 2 males, 2 females KIZCAS [KIZ0121459-0121462]; 2 males, 2 females NIAES; 2 males, 2 females NMNS; 2 males, 2 females RAB; 2 males, 2 females RIFID; 2 males, 2 females SYU; 2 males, 2 females USNM; 2 males, 2 females ZIN; 20 males, 20 females JXAU).

Description.

Male. 3.58-4.01 mm long (mean = 3.78; n = 20); 2.75-2.95 times as long as wide. Head and pronotum dark brown, disc of elytra reddish brown becoming dark brown, declivity of elytra nearly black.

Head. Frons flat, slightly shining, with irregular large punctures; finely, sparsely punctured above the epistoma, bearing bristly, erect, long setae, weakly concave, smooth around short median line, upper part of frons with scattered, coarse punctures, the punctures with moderate, semierect, dorsally directed setae. Antennal scape clavate with scattered, forwardly directed hairs on apical half; club oval, flattened, evenly covered with short setae. Labial palps two-segmented, with basal segments fused along the midline.

Pronotum. About 1.2 times longer than wide, shining, no mycangial pores, the lateral femoral grooves angulate anteriorly, pronotum widest in front of the grooves, with finely, scattered, irregular punctures, a few semierect backwardly pointed hairs close to anterior margin, median line extending about 1/4 from base.

Scutellum. Depressed below level of elytra, with a median longitudinal groove between lateral carinae.

Elytra. About 2.0 times as long as wide, about 1.4 times as long as pronotum. Surface of disc smooth, shining, striae distinctly impressed for almost their entire length, except striae 6 and 7, other striae with circular, distinct, shallow punctures, the bases of striae 1 and 2, striae 3 and 4, respectively, conjoint, more impressed; interstriae slightly raised on disc, interstriae 1, 3 and 5 distinctly raised and conjoint at base, interstriae 8 and 9 fused at apex of disc, forming ventral, rounded angle; cylindrical declivity obliquely truncate, acutely margined all around except at sutural apex, strongly concave, forming a cup-like structure, surface shining, with 4 rows of longitudinal granules bearing erect, long, golden setae, a row of sparse, medially directed, erect golden setae at the inner margin of declivity, elytral apex broadly emarginate, the main emargination approximately U-shaped, about as wide as deep, extending about 1/3 of the height of the declivity, at its inner end a much smaller, V-shaped second emargination (Fig. 1A, D ).

Protibia. Five transverse carinae at tibial apex, transverse rugae at base.

Abdomen. Abdominal ventrites 1-4 moderately finely punctured, with irregular rows of erect, short hairs at both sides posteriorly, ventrite 5 strongly concave at middle, with dense, large, circular punctures.

Female. 3.64-4.42 mm long (mean = 3.96 mm; n = 20); 2.79-2.93 times as long as wide. Head and pronotum brown, disc of elytra reddish brown becoming dark brown to apex.

Head. Similar to male, but frons flatter, very shining, smooth, with shallow, small punctures; finely, sparsely punctured above the epistoma, bearing bristly, erect, long setae; very shallowly concave in median line, upper part of frons with scattered, shallow, small punctures, the punctures with moderate, semierect, dorsally directed setae.

Pronotum. Similar to male.

Elytra. About 1.8 times as long as wide, about 1.5 times as long as pronotum, sides subparallel. Similar to male, but disc of elytra shining, with dense, longitudinal, semierect, backwardly pointed hairs at apex and declivity, striae weakly impressed, interstriae smoother, declivity vertical, a few irregularly granules, sparsely hairy.

Protibia. Three transverse carinae at tibial apex, fine, confused granules at base.

Abdomen. Surface of abdominal ventrites smooth, rounded, sparsely hairy, ventrite 5 without concavity, punctures shallow.

Etymology.

The species is named for Roger A. Beaver to honor his contributions to the study of platypodines and scolytines.

Host plants.

Castanopsis carlesii (Hemsl.) Hayata, C. fargesii Franch. ( Fagaceae ), Liquidambar formosana Hance ( Altingiaceae ), Phoebe zhennan S.K.Lee & F.N.Wei ( Lauraceae ), Paulownia fortunei (Seem.) Hemsl. ( Paulowniaceae ), Vernicia montana Lour. ( Euphorbiaceae ).

Distribution.

China (Jiangxi, Fujian).

Diagnosis.

The species is placed in Crossotarsus because it possesses a combination of characters similar to that cited in the introduction.

Crossotarsus beaveri is very similar to Crossotarsus brevis (Browne, 1975) (new combination, see below) and Crossotarsus platypoides (Browne, 1955). They can be easily distinguished from other Crossotarsus species by the male elytral apex truncate with a large, circular, concave declivity. The elytral apex of male of C. beaveri and that of C. brevis possess a deep, acutely margined declivity, with a broad, almost circular, apical emargination.

Figures

Figure 1. Male of Crossotarsus beaveri sp. nov. A dorsal view B head C lateral view D declivity. Scale bars: 0.5 mm.

Figure 2. Female of Crossotarsus beaveri sp. nov. A dorsal view B head C lateral view D declivity. Scale bars: 0.5 mm.