Pyrrhalta formosanensis, Lee & Bezděk, 2021

Lee, Chi-Feng & Bezdek, Jan, 2021, Revision of the genera Xanthogaleruca Laboissiere, 1932 and Pyrrhalta Joannis, 1865 (Coleoptera, Chrysomelidae, Galerucinae) of Taiwan, with type designation of Galerucella lineatipes Takei, ZooKeys 1039, pp. 1-108 : 1

Pyrrhalta formosanensis sp. nov. Figs 26B , 27A-C , 28

Types.

Holotype ♂ (TARI), Taiwan. Kaohsiung, Tienchih (天池), 2.VII.2009, leg. M.-H. Tsou. Paratypes. 1♂, 12♀, same data as holotype; Hualien: 1♂ (TARI), Kuanyuan (關原), 2.VII.2008, leg. M.-H. Tsou; 1♂ (TARI), Pilu (碧綠), 6.VII.2018, leg. H.-F. Lu; Ilan: 1♀ (TARI), Chienching trail (見晴步道), 23.IV.2019, leg. M.-D. Chen; 1♀ (TARI), Tsuifenghu (翠峰湖), 15.VIII.2007, leg. S.-S. Li; Kaohsiung: 1♂ (TARI), Chungchihkuan (中之關), 10.VI.2015, leg. C.-F. Lee; Nantou: 1♂ (TARI), Meifeng (梅峰), 24-26.VI.1981, leg. K. S. Lin & W. S. Tang; 1♂ (TARI), Piluhsi (碧綠溪), 8.VII.2015, leg. C.-F. Lee; 1♂ (TARI), Tsuifeng (翠峰), 30.VII.2014, leg. C.-F. Lee.

Diagnosis.

Legs reddish brown; tibia of middle leg with apical spine; tarsomere I modified. Sides of ventrite V strongly shortened in males.

Description.

Length 4.6-5.5 mm, width 2.4-2.9 mm. Body color (Fig. 27A-C ) reddish brown; head black but antennae dark brown. Eyes small, interocular space 2.62-2.69 × diameter of eye. Antennae filiform in males (Fig. 28A ), length ratios of antennomeres I-XI 1.0: 0.6: 0.8: 0.8: 0.6: 0.7: 0.6: 0.6: 0.6: 0.6: 0.8, length to width ratios of antennomeres I-XI 2.8: 1.9: 2.5: 2.4: 2.0: 2.2: 2.0: 1.9: 1.9: 2.0: 2.4; similar in females (Fig. 28B ), length ratios of antennomeres I-XI 1.0: 0.5: 0.7: 0.6: 0.6: 0.6: 0.6: 0.6: 0.6: 0.5: 0.7, length to width ratios of antennomeres I-XI 3.2: 2.0: 2.4: 2.2: 1.9: 2.0: 1.9: 1.7: 1.7: 1.6: 2.2. Pronotum and elytra convex. Pronotum 2.1-2.2 × wider than long, disc with dense, extremely coarse punctures and extremely short pubescence, with transverse ridge near apical margin deflexed near antero-lateral corners, with median longitudinal and lateral depressions; lateral margins moderately rounded, apical margin slightly concave, basal margin straight; anterior and posterior setiferous punctures slightly erect. Elytra elongate and broad, parallel-sided, 1.4-1.5 × longer than wide; disc with dense, extremely coarse punctures and extremely short pubescence. Apical spur of tibia of middle leg slender (Fig. 28G ), tarsomere I axe-shaped in lateral view, with narrow basal part and expanded apical 2/3, posterior angles of expanded part narrowly rounded (Fig. 28M ) in males. Aedeagus (Fig. 28C-E ) extremely asymmetric in dorsal view, inner margin of right side expending at apical 1/3, covering right side of ostium, lateral margin of right side expanding downwards, with a notch at middle; inner margin of left side expanding inwards at basal 2/5 and apical 2/5; primary endophallic sclerite elongate, several fine teeth on apex. Sclerotized gonocoxae (Fig. 28J ) transverse, both gonocoxae separated, with several long setae near apices. Ventrite VIII (Fig. 28H ) transverse; disc with dense, long setae along apical margin; spiculum short. Receptacle of spermatheca (Fig. 28I ) slightly swollen; pump short and strongly curved; sclerotized proximal spermathecal duct wide and short. Apical margin of abdominal ventrite V slightly concave medially, with deep triangular depression at middle in males, sides of abdominal ventrite V shortened, sides of basal margin of abdominal ventrite IV expanding downwards in males (Fig. 28K ); only slightly concave in females (Fig. 28L ).

Remarks.

Adults of P. formosanensis sp. nov. are similar to those in Taiwanese populations of P. semifulva with their reddish bodies, but differ in the reddish brown scutellum, legs, and thoracic ventrites (Fig. 27B ) (black scutellum, legs, and thoracic ventrites (Fig. 27E ) in P. semifulva ), modified sides of abdominal ventrite V (Fig. 28K ), and mesotarsomere I of middle leg (Fig. 28M ) in males, and very characteristic aedeagus (Fig. 28C-E ).

Food plant.

Adults feed on flowers of Prunus campanulata Maxim. ( Rosaceae ) (Fig. 26B ).

Distribution.

The species is widespread at mid-altitudes (1,500-2,500 m) in Taiwan.

Etymology.

This species is named after Taiwan, a beautiful island.

Figures

Figure 26. Field photographs of adults of Pyrrhalta species on host plants A P. tsoui Bezdek & Lee B P. formosanensis sp. nov. C P. semifulva (Jacoby) D P. ishiharai Kimoto.

Figure 27. Habitus of Pyrrhalta formosanensis sp. nov. and P. semifulva (Jacoby) A P. formosanensis sp. nov., female, dorsal view B ditto, ventral view C ditto, lateral view D P. semifulva, from Taiwan, female, dorsal view E ditto, ventral view F ditto, lateral view.

Figure 28. Diagnostic characters of Pyrrhalta formosanensis sp. nov. A antenna, male B antenna, female C aedeagus, dorsal view D ditto, left-side view E ditto, ventral view F ditto, right-side view G apex of tibia of middle leg, male H abdominal ventrite VIII I spermatheca J gonocoxae K abdominal ventrite V, male L abdominal ventrite V, female M tarsi of middle leg, male.