Tanytarsus sinuatus Goetghebuer, 1936

Tanytarsus sinuatus Goetghebuer, 1936 View in CoL

( Figs 11–14 View FIGURE 11 View FIGURE 12 View FIGURE 13 View FIGURE 14 )

Tanytarsus sinuatus Goetghebuer, 1936 View in CoL in Thienemann 1936: 185.

Tanytarsus alpicola Goetghebuer, 1950: 5 View in CoL .

Tanytarsus sinuatus Reiss & Fittkau 1971: 134 View in CoL .

Material examined. Holotype: male ( RBINS: 18.073), Germany, Bavaria, 1935, leg. et det. M. Goetghebuer. GoogleMaps 3 males (SHOU & BOLD sample ID: XL676, XL678, XL679), Italy, Trentino-Alto Adige/Sudtirol, Trento , Peio , Stilfser Joch National Park , Glacier Lake below the Lago Marmotta , 46.434723°N, 10.677778°E, 2633 m, a.s.l., sweep net, 8.VII.2017, leg. X.L. Lin. GoogleMaps 3 larvae (SHOU & BOLD sample ID: XL55, XL438, SHOU sample ID: XL56), China, Xizang, Chamdo City , Ranwu Village , Ruanwu Lake , 29.50581°N, 96.76048°E, 3963 m a.s.l., 10.VII.2014, leg. X.L. Lin; GoogleMaps 3 larvae (SHOU & BOLD sample ID: XL3586, XL3587, XL3593), China, Qinghai, Bande Lake , 34.2161°N, 92.0769°E, 4600 m a.s.l., 12.VI.2020, leg. Jia-Ping Chen; GoogleMaps 2 larvae (SHOU & BOLD sample ID: XL2722, XL2723), China, Yunnan, Nu jiang of the Lisu Autonomous Prefecture , Lanping Bai and Pumi Autonomous County, Erdaobaihe Village , Glacial Lake , 26.5897222°N, 99.0213899°E, 3789 m a.s.l., 24.V.2018, leg. X.L. Lin; GoogleMaps 1 larva (SHOU & BOLD sample ID: XL3843), China, Xizang, Naqu , Nima Wetland , 31.7128°N, 92.0582°E, 4628 m a.s.l., 5.IX.2020, leg. Yu Peng; GoogleMaps 1 larva (SHOU & BOLD sample ID: XL3828), China, Xizang, Nyingchi City, Bayi , 29.7617°N, 94.742°E, 3332 m a.s.l., 28.IIX.2020, leg. Yu Peng. GoogleMaps

Diagnostic characters. The adult male of Tanytarsus sinuatus can be distinguished from known species of the T. norvegicus species group by the following combination of characters: Frontal tubercles ( Fig. 11B View FIGURE 11 ) cylindrical. Thorax ( Fig. 11C View FIGURE 11 ) pale brown with dark brown on scutum and parapsidal suture, light brown on median anepisternum II, preepisternum and epimeron II. Ac absent. LR 1 1.48–1.50. Anal point ( Fig. 11D View FIGURE 11 ) slender triangular, tapering near the apex, with 9–13 spinulae in single row between large parallel crests. Superior volsella ( Fig. 11E View FIGURE 11 ) roughly slender elliptical in outline but extended into a robust tooth on the anal median side. Digitus ( Fig. 11F View FIGURE 11 ) is thickened distally, significantly surpassing superior volsella and bears a small, well-discernible protuberance or lobe at mid length. Stem of median volsella ( Fig. 11F View FIGURE 11 ) clublike thickened distally, with several lamellae of the broad awl-type. Inferior volsella ( Fig. 11F View FIGURE 11 ) distal part round head-like.

Larva (n = 5)

Total length 5.4–6.8, 6.1 mm.

Head Capsule ( Fig. 12B View FIGURE 12 ). Length 357–423, 385 μm, width 322–378, 350 μm, length/width 1.05–1.14, 1.10; mental and mandibular teeth dark brown. Antennal pedestal ( Fig. 13 View FIGURE 13 A-B) 53–59, 57 μm long.AHR 0.13–0.17, 0.15; AAR 0.48–0.62, 0.53. Antenna shorter than head length, 5-segmented. Antennal segment length (in μm): 93–117, 108; 28–36, 32; 8–13, 11; 6–8, 7; 3–6, 5. AR 1.74–2.34, 1.97. Antennal blade 25–37, 31 μm long. LO stems + stylus 32–43, 36 μm long; LOR 1.44–1.70, 1.57. Style 6–9, 8 μm long. Mandible ( Fig. 13 View FIGURE 13 C-D) 135–156, 148 μm long, 54–69, 62 μm wide, one ventral apical tooth, three ventral inner teeth, 4 dorsal teeth and 1 robust dorsal plate; seta subdentalis thick and curved, 51–59, 56 μm long, reaching beyond apex of dorsal tooth; seta interna well-developed with four main branches. Mentum ( Fig. 13 View FIGURE 13 E-F) 106–122, 111 μm wide, with 11 teeth; median tooth lingulate with small lateral notches; ventromental plate 117–132, 125 μm wide, 26–32, 29 μm long, MVR 0.85–0.93, 0.89. Premandible ( Fig. 14 View FIGURE 14 A-B) 76–88, 83 μm long, with five teeth in addition to lateral spine; premandibular brush well-developed. Labrum ( Fig. 14C View FIGURE 14 ) with S I pectinate and chaetae plumose; S II long, simple; clypeal seta S3 long, simple. Labral lamella pectinate. Pecten epipharyngis consisting of three plumose lobes. Maxilla ( Fig. 14D View FIGURE 14 ) with two long and one short lacinial chaetae, palp well-developed, postoccipital margin darkly pigmented. Postmentum 154–171, 163 μm long.

Abdomen. Procercus 48–52, 51 μm high, with eight anal setae, 530–568, 550 μm long. Anal tubules two pairs,130–195, 162 μm and 107–132, 114 μm long.

Remarks: The larvae of Tanytarsus sinuatus and T. dawai are very similar, but can be distinguished by following morphological characters: T. dawai has a higher LOR (1.92–2.63), whereas LOR = 1.44–1.70 in T. sinuatus . In addition, the median tooth on the mentum exhibits a rounded shape in T. dawai , whereas it bears lateral protrusions in T. sinuatus .

Distribution. Austria, China (Qinghai, Xizang, Yunnan), Germany, Italy and Norway.