Siemssenius cheni Lee

Lee, Chi-Feng, 2016, Review of the genus Siemssenius Weise, 1922 (Coleoptera: Chrysomelidae: Galerucinae) from Taiwan, with descriptions of five new species, Zootaxa 4158 (3), pp. 367-384 : 368

Siemssenius cheni Lee , sp. nov.

( Figs 1 A–1B, 2A– 2I)

Type locality. Taitung county, Hsiangyang (向陽), 23°14’53”N, 120°59’09”E, 2300 m.

Type material (n= 4). Holotype ♂ ( TARI): Taitung: Hsiangyang (向陽), 20.VI.2011, leg. C.- F. Lee . Paratypes: 1♂ ( TARI), same data as holotype ; 1♂ ( TARI), same locality, 31.V.2011, leg. J.- C. Chen ; 1♀ ( TARI), same locality, 18.VII.2014, leg. W.- C. Huang.

Description. Length 8.2–9.6 mm, width 3.8–5.3 mm. General color yellow, but head, scutellum, femora, elytra, tarsi, and apices of tibiae black; antenna apically paler ( Figs 1 A–1B). Antenna filiform, relatively shorter in male ( Fig. 2 A), 0.8x as long as body, antennomeres III–V apically widened, length ratios of antennomeres III to XI about 1.0: 1.4: 1.4: 1.2: 1.4: 1.2: 1.2: 1.2: 1.6, and length to width ratios of antennomeres III to XI about 3.0: 3.7: 3.7: 3.3: 4.1: 3.8: 4.5: 4.4: 6.1; relatively longer in female ( Fig. 2 B), about 0.9x as long as body, antennomeres III–V apically broadened, length ratios of antennomeres III to XI 1.0: 1.3: 1.2: 1.1: 1.1: 0.9: 1.0: 1.0: 1.4, and length to width ratios of antennomeres III to XI 4.1: 3.8: 3.7: 3.2: 3.4: 2.9: 4.1: 4.0: 4.7. Apical margin of abdominal ventrite V with two well developed incisions in male, surface with deep, wide, longitudinal groove, apically expanding into entire area between incisions; apical margin of ventrite IV with very small incision midway ( Fig. 2 E). Aedeagus concave and basally widened, weakly curved in lateral view; apico-lateral angles obtuse, narrow in lateral view, base obtusely angulate; middle of apical margin with a long, broad tube-like process, wide in lateral view, apex with median notch; dorsal process subapically and strongly swollen in lateral view but slender and subapically narrowed in dorsal view, apex pointed and triangular in lateral view ( Figs 2 C–2D). Abdominal ventrite V not modified in female, apical margin truncate, disc without depression ( Fig. 2 F); apical margin of ventrite IV straight. Gonocoxae reduced. Ventrite VIII ( Fig. 2 H) heart-shaped, with short spiculum and sparse, elongate setae along apical margins of triangulate processes. Tergite VIII ( Fig. 2 G) with apex rounded and dense setae on disc. Receptacle of spermatheca ( Fig. 2 I) weakly swollen, barely separated from pump, pump much narrower and longer, sharply curved; proximal spermathecal duct long and narrow.

Diagnosis. Siemssenius cheni sp. nov. is similar to S. metallipennis in possessing yellow body and black head, tibiae, tarsi and apices of femora. But, adults of this new species have black elytra (greenish or purplish bronze elytra in S. metallipennis ) and obtuse apico-lateral angles of the aedeagus.

Host plant. Lonicera acuminata Wall., 1832 (Caprifoliaceae) ( Fig. 3 A).

Etymology. This new species is named after Mr. Jung-Chan Chen, a member of the TCRT and first to collect this new species.

Distribution. Only known from the type locality, Hsiangyang (向陽) in southeast Taiwan ( Fig. 4 ).

Figures

FIGURES 1. Habitus of Siemssenius species. 1 A. S. cheni Lee, sp. nov., dorsal view; 1 B. Same, ventral view; 1 C. S. metallipennis (Chûjô), dorsal view; 1 D. Same, ventral view.

FIGURES 2. Diagnostic characters of Siemssenius cheni Lee, sp. nov. 2 A. Antenna, male; 2 B. Antenna, female; 2 C. Penis, lateral view; 2 D. Penis, dorsal view; 2 E. Abdominal ventrites III – V, male; 2 F. Abdominal ventrite V, female; 2 G. Abdominal tergite VIII, female; 2 H. Abdominal ventrite VIII, female; 2 I. Spermatheca.

FIGURES 3. Habitat photographs of Siemssenius species. 3 A. S. cheni Lee, sp. nov. and the host plant Lonicera acuminata Wall., 1832; 3 B. S. metallipennis (Chûjô, 1962); 3 C. Lonicera acuminata Wall., 1832; 3 D. Adult of S. tsoui Lee, sp. nov. feeding on leaves of L. hypoglauca Miq., 1866; 3 E. Adult of S. tsoui Lee, sp. nov. feeding on flower buds of L. hypoglauca Miq., 1866; 3 F. Adult of S. tsoui Lee, sp. nov. and the host plant Hydrangea angustipetala Hayata, 1911.

FIGURE 4. Distribution map of Taiwanese species of Siemssenius, solid line: 1000 m, broken line: 2000 m. Red spots: S. rufipennis (Chûjô); blue spots: S. tsoui sp. nov; gray spots: S. liui sp. nov.; pink spots: S. yuae sp. nov.; orange spots: S. metallipennis (Chûjô) and S. rufipennis (Chûjô); green spot: S. jungchani sp. nov.; yellow spot: S. cheni sp. nov.