Gymnetron vittipenne Marseul, 1876

Jiang, Chunyan & Zhang, Runzhi, 2015, The genus Gymnetron from China with description of pre-imaginal stages of G. miyoshii, G. auliense and G. vittipenne (Coleoptera, Curculionidae), ZooKeys 534, pp. 61-84 : 68-70

Taxon classification Animalia Coleoptera Curculionidae

Gymnetron vittipenne Marseul, 1876

Gymnetron vittipenne Marseul, 1876: 383.

Gymnetron apicale Faust 1885: 187.

Gymnetron vittipenne var. suturiferum Reitter 1907: 32.

Description.

Adult (Figures 5-6): Sides of pronotum covered with dense, imbricated, broad scales; uncus of metatibiae strongly enlarged at apex in male; first tarsal segment on venter covered with very dense and long setae in male; ductus of spermatheca sclerotized at base near insertion with spermatheca. Elytra parallel-sided, with reddish and black integument covered with moderately dense, recumbent to erect, seta-like scales arranged in three very irregular rows on each interstria; rostrum in lateral view slightly curved, angulate along dorsal margin at antennal insertion and weakly narrowed at apical third in male, strongly curved, cylindrical and of same length from base to apex in female ( Caldara 2008).

Egg: unknown.

Mature larva: measurements (mm): body length: 5.00-5.20 (n = 2), width: 1.60-2.00 (n = 2); capsule length (in dorsal view): 0.70-0.86 (n = 4), width: 0.57-0.68 (n = 4).

It differs from Gymnetron miyoshii by: General appearance (Figure 26): size greater. Head: Size greater, endocarinal line long, more than half as long as frons; hypopharingeal bracon distinct; clypeus transverse, bearing two pairs of cls, cls1 nearly same length as cls2, located in one line, parallel to clypeus, sensilla distinct; antenna (Figure 27) with one segment, contiguous with frontal suture, with one spinose and one tiny seta-like sensilla. Mouthparts (Figures 28-32): labrum (Figure 29) transverse, partly sclerotic, anterior margin nearly straight, posterior margin weakly extended medially into clypeal zone, with three pairs of lrms, lrms2 a bit shorter than lrms1, both centrally localized, lrms3 same length as lrms1, close to distal margin of labrum, with one mds, subequal to lrms2; epipharynx (Figure 30) with two pairs of als, three pairs of ams, one pair of mes, sensilla absent. All epipharyngeal setae stout, short and apically rounded; labium (Figure 31) membranous except sclerotized area. Labial palpus with one segment, longer than wide distinctly, with one pair of sensilla, apically flattened with dense crenulate setae. Premental sclerite (Pmsc) distinctly posteriorly and laterally dilated, U-shaped, with one pair of sensilla and one pair of long prms. Ligulate area with two pairs of tiny lgs, lgs1 same lengtgh as lgs2, with one pair of sensilla. Postlabium partly sclerotized, with two pairs of plbs at membranous area, plbs1 long, plbs2 short, one quarter as long as plbs1.; Maxillae with maxillary palpus (mxp) (Figures 31-32) two segmented, basal segment distinctly wider than long, with one pair of sensilla and one pair of short mxps, accessory appendage absent. Apical segment longer than wide, with one pair of sensilla, apically flattened with dense short irregular speculate setae. Mala with five robust dms, dms1-5 gradually shorter than the former one and four thin vms. Stipes bearing one sts, three palpiferal pfs and two sensilla, sts strong and long, basally medioventral, pfs1 short, located near mala, one third as long as pfs2, pfs2 basally medioventral, same length pfs3, pfs3 lateroventral. Cardo completely divided from stipes. Thorax (Figure 26): Pronotum with six pns. Spiracle (Figure 33) bicameral, air-tube distinctly longer than diameter of circular peritreme, pointing basad. Pedal area (Figure 34) distinct, with five setae; Mesonotum with two folds, prodorsum with one prs. Postdorsum with two pds, one dls transversally aligned. Pedal area same as prothoracic; Metanotum same as mesonotum. Abdomen (Figure 26): with seven spiracles on segments I-VII, size similar, all anterolateral and unicameral, each with single annulated air-tube, distinctly longer than diameter of circular peritreme, pointing basad. Abd I-VII: tergites with two folds, prodorsum with one tiny prs, postdorsum with soft protuberance posteriorly, with two pds, pds1 short, half as long as pds2. All setae shorter than thoracic setae; Abd VIII: pds1 short, half as long as pds2.

Pupa (Figures 35-37): measurements (mm): length: 4.75-4.85 (n = 4), width: 1.60-2.00 (n = 4).

It differs from Gymnetron miyoshii by: General appearance: size greater. Head: head yellow-gray with indistinct yellow stripes in middle, two pairs of pas, pas1 situated in middle of frons, pas2 situated at middle margin of eyes. Thorax: prothorax bearing a lightly pigmented tubercle, apically deeply bifurcate. Pronotum with three as, two sls, one ds and two pls. As and sls1, pls subequal, strong and long, pls1 and pls2 in one transverse row, sls2 and ds short; Mesonotum with three msns on scutellum. Abdomen: segment I-VII with tergite bearing two setae. Spiracular area with two ss; Legs: pro-, meso- and metafemora apically bearing one pair of slightly outcurved fes, apex with grey circular pigmented area.

Specimen examined.

CHINA: Xinjiang: Talaticun, Qinghe (46°40.53'N; 90°27.74'E, 1285m), 28-VII-2013, Veronica oxycarpa Boiss., leg Chunyan Jiang (33); Hualin Park (47°51.75'N; 88°07.18'E, 886m), 5-VIII-2013, leg You Li (1).

Biological notes.

After collecting the host plants Veronica oxycarpa Boiss. with galls on 28-VII-2013, 10 larvae and 20 pupae were obtained on 1-VIII-2013.

Remarks.

This species has been recorded from Armenia, Bulgaria, Croatia, Greece, Iran, Iraq, Kazakhstan, Lebanon, Palestine, Slovakia, Syria, Tajikistan, Turkey, Turkmenistan and Uzbekistan. This species is a new record for China.