Pyrrhalta tahsiangi, 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 tahsiangi sp. nov. Figs 5G-I , 7C, D , 10

Types.

Holotype ♂ (TARI), Taiwan. Ilan: Tsuifenghu (翠峰湖), 4.VII.2010, leg. M.-H. Tsou. Paratypes. 3♂, 8♀ (TARI), same data as holotype; Ilan: 6♀ (TARI), Yuanyanghu (鴛鴦湖), 23.VIII.2011, leg. M.-H. Tsou; 1♂, 5♀ (TARI), same but with "leg. H. Lee"; 7♀ (TARI), Taipingshan (太平山), 25.V.2009 (reared from larvae), leg. C.-F. Lee.

Diagnosis.

Elytra smooth, lacking longitudinal ridges; yellowish brown, with brown longitudinal stripes.

Description.

Length 4.8-5.6 mm, width 2.1-2.4 mm. Body color (Fig. 5G-I ) yellowish brown; antennae brown, four apical antennomeres darkened; elytra with two pairs of wide, poorly defined, longitudinal brown stripes, one pair near suture, the other arising from humeral calli. Eyes small, interocular space 2.55-2.58 × diameter of eye. Antennae filiform in males (Fig. 10A ), length ratios of antennomeres I-XI 1.0: 0.6: 1.2: 1.0: 0.9: 0.9: 1.0: 0.9: 0.9: 0.8: 1.0, length to width ratios of antennomeres I-XI 2.6: 2.2: 4.3: 3.8: 3.8: 3.3: 3.4: 3.3: 3.0: 3.0: 4.0; similar in females (Fig. 10B ), length ratios of antennomeres I-XI 1.0: 0.7: 1.1: 1.0: 1.0: 1.0: 1.0: 0.9: 0.9: 0.8: 1.1, length to width ratios of antennomeres I-XI 2.6: 2.6: 4.0: 3.6: 3.5: 3.4: 3.7: 3.2: 3.4: 3.3: 4.3. Pronotum and elytra convex. Pronotum 1.8-1.9 × wider than long, disc smooth; with extremely dense, coarse punctures, and short pubescence, with median longitudinal and lateral depressions; lateral margins slightly rounded, widest at apical 1/3, apical and basal margin slightly concave; anterior and posterior setiferous punctures slightly erect. Elytra elongate and broad, parallel-sided, 1.7 × longer than wide; disc rugose, with dense, coarse punctures, and short pubescence. Apical spur of tibia of middle leg slender (Fig. 10F ), and tarsomere I ax-shaped in lateral view, with narrowed basal half and expanded apical half (Fig. 10H ) in males. Aedeagus (Fig. 10C, D ) broad in dorsal view, 5.0 × longer than wide, parallel-sided, asymmetric, curved at middle, apex narrowly rounded; ostium large, mostly covered by membrane; straight but strongly curved near base in lateral view, apex narrowly rounded; primary endophallic sclerite elongate, 0.5 × as long as aedeagus, with several fine teeth near apex. Only apices of gonocoxae (Fig. 10K ) sclerotized, short, with several short setae near apex, and four long setae near apex. Ventrite VIII (Fig. 10E ) well sclerotized, apex truncate, plate-shaped and projecting, several extremely short setae along lateral margin and apical area, apical margin with cluster of long setae near middle, spiculum extremely long. Receptacle of spermatheca (Fig. 10G ) swollen; pump short and strongly curved; sclerotized proximal spermathecal duct wide and extremely short. Apical margin of abdominal ventrite V slightly concave medially and with deep depression in males (Fig. 10J ); while slightly concave and with short internal ridge at middle in females (Fig. 10I ).

Remarks.

Adults of this new species are easily separated from other members of the species group by their yellowish brown elytra bearing longitudinal brown stripes and modified tarsi of the middle leg. In addition, some putative autapomorphies are found in genitalic characters, including the characteristic shape of the aedeagus and single endophallic sclerite bearing teeth near the apex (Fig. 10C ). The truncate apex of abdominal ventrite VIII in females is also diagnostic (Fig. 10E ) (tapering apex of abdominal ventrite VIII in females of others).

Host plants.

adults feed on leaves of Rhododendron chilanshanense Kurashige (Fig. 7C ); larvae and adults feed on leaves of R. mariesii Hemsl. and E. H. Wilson ( Ericaceae ) (Fig. 7D ).

Biology.

The first author and Mr Ta-Hsiang Lee collected young larvae on tender leaves of Rhododendron mariesii May 1, 2009 in Taipingshan, northeastern Taiwan, and reared them in the laboratory. Newly eclosed adults emerged from soil May 25. Mr. Mei-Hua Tsou collected a number of adults July 5, 2010 at the same locality (= Tsuifenghu) (Fig. 7C ). The first author, Mrs. Hsueh Li, and Mr. Mei-Hua Tsou found adults feeding on leaves of R. chilanshanense (Fig. 7D ) August 23, 2011 in Yuanyanghu, northeastern Taiwan.

Distribution.

This new species is restricted to mid-altitudes (1,000-2,000 m) in northeastern Taiwan.

Etymology.

Dedicated to Mr. Ta-Hsiang Lee. He and the first author were the first to find larvae of this new species and rear them successfully to adults.

Figures

Figure 5. Habitus of Pyrrhalta gressitti Kimoto, P. houjayi sp. nov., and P. tahsiangi sp. nov. A P. gressitti, male, dorsal view B ditto, ventral view C ditto, lateral view D P. houjayi sp. nov., male, dorsal view E ditto, ventral view F ditto, lateral view G P. tahsiangi sp. nov., male, dorsal view H ditto, ventral view I ditto, lateral view.

Figure 7. Field photographs of Pyrrhalta gressitti Kimoto and P. tahsiangi sp. nov. on host plant A mature larva of P. gressitti B P. gressitti, adult C adult of P. tahsiangi on Rhododendron chilanshanense D adult of P. tahsiangi on R. mariesii.

Figure 10. Diagnostic characters of Pyrrhalta tahsiangi sp. nov. A antenna, male B antenna, female C aedeagus, dorsal view D ditto, lateral view E abdominal ventrite VIII F apex of tibia of middle leg, male G spermatheca H tarsi of middle leg, male I abdominal ventrite V, female J abdominal ventrite V, male K gonocoxae.