Chrysodema (Chrysodema) hainanensis, Qi & Ai & Song, 2022

Qi, Zhi-Hao, Ai, Hong-Mu & Song, Hai-Tian, 2022, Notes on the genus Chrysodema from China (Coleoptera: Buprestidae: Chrysochroinae), with one new species and one new record, Zootaxa 5099 (3), pp. 355-368 : 356-357

Chrysodema (Chrysodema) hainanensis sp. nov.

(Chinese common name: 海南fl彩吉丁)

( Figs 1A–C , 2A–J , 5A, 5B, 5F–H , 6D, 6E )

Type localiy. China, Hainan Island, Sanya City, Tianya District , Lizhiling Mountain .

Type specimens. Holotype ♂ ( FAFS): CHINA • Lizhiling Mountain, Tianya District, Sanya City , Hainan Province; 18°21'N, 109°27'E, alt. 390 m; 19.VI.2021; Hai-Tian Song leg. Paratypes 4 ♂♂, 5 ♀♀ ( CHTS); same collection data as for holotype; Hai-Tian Song & Zhi-Hao Qi leg. • 2 ♀ ( CHTS); same collection data as for the preceding; 18.VI.2021 • 4 ♀ ( CHTS); same collection data as for the preceding; alt. 350 m; 17.VI.2021 • 2 ♂♂, 2 ♀♀ ( CHTS); same collection data as for the preceding; 17.VI.2021; Shi-Jie Lu & Jia-Sheng Lu leg. • 6 ♀♀ ( CHTS); same collection data as for the preceding; 29.VI.–14.VII.2020; Jia-Sheng Lu leg. • 1 ♀ ( CHTS); same collection data as for the preceding; VII.2021; Jia-Sheng Lu leg. • 1 ♀ ( CHTS); Sanya City , Hainan Province; V–VI.2019; local collector leg . • 1 ♀ ( CHTS); Liuluo Valley, Tianya District, Sanya City , Hainan Province; VIII.2020; Rong-Jia Chen leg. • 1 ♀ ( CHTS); same collection data as for the preceding; VI.2020 • 1 ♂ ( CHTS); Jianfengling National Forest Park, Ledong Li Autonomous County, Hainan Province; 24.IV.2019; Shi-Liang Mo leg.

Description of holotype. Well preserved ♂ specimen ( Fig. 1A–C , 2C , 5A ). Length 2.03 cm, width 0.66 cm, length/width ratio: 3.08.

Body metallic green, shiny. Impunctate (or micropunctate) areas on dorsal side dark blue to purple. Pronotum with bright golden green mixed macropunctation, principal impressions with golden green mixed punctation. Punctation on elytra variegate golden green mixed, and elytra with metallic green regular stripes; principal and lateral impressions bright golden-green; lateral margin metallic green. Ventral side bright metallic green. Legs including tarsi metallic green, ventral pads black, basally brown. Labrum, maxillae and labium yellowish-brown; maxillar and labial palpi brown to black. Scape and pedicel metallic green, remaining antennomeres brownish-black.

Pronotum moderately densely macropunctate with narrow and sparsely micropunctate interspaces. Medial line well visible with longitudinal dense macropunctation from both sides of medial line to fifth of lateral margin, followed by relatively sparse punctation with many punctures connected and forming obviously narrow longitudinal impressed lines (principal impressions) at three fifths of medial line to lateral margin, next to lateral margin are moderately densely punctate. Medial impressions shallow but distinct. Principal impressions distinct and weakly delimited from disc. Lateral impressions not obvious. Lateral margin relatively straight.

Each elytron regularly with four slightly but distinctly convex costae, 1st and 2nd costa united at both base and apex of elytron, gradually narrowed. 1st slightly wider than 2nd. 3rd costa starts from lateral base and ends at apical third of elytron, 4th costa starts at basal fourth of elytron near lateral edge and ends at apex. Punctation always regular. Subscutellar interval (row of puncture distributed along basal part of elytral suture) denser at basal fifth. Other punctures form 4 wide longitudinal intercostal intervals on each elytron (1st–4th intercostal intervals). Small oval impression occurrs at base of 2nd intercostal interval and obvious oval impression at about basal third. Lateral impression (4th intercostal interval) with condensed wax layer thus appears like elongate opaque yellow stripe. Large elliptical principal impression protrudes from lateral impression to 3rd intercostal interval at apical third of elytron, and interrupts 3rd intercostal interval. Lateral impression narrowed after large elliptical principal impression, and then rewidening, before narrowingly evenly to apex. Epipleura gradually narrowed at apical third of elytron, with continuous teeth.

All tibiae and femora are metallic green, with dense punctation and short setae. Outer margin of apex of protibia has nearly triangular protrusion.

Ventral side of body ( Fig. 1B ) and lateral sides ( Fig. 1C ) of all abdominal ventrites very densely punctate. Ventrite V triangularly excavated at tip ( Fig. 2C ).

Aedeagus ( Fig. 5A ) length: 5.22 mm, width: 1.02 mm, length/width ratio: 5.12. Apices of parameres subtruncate, inner tip relatively rounded, lateral margin of parameres relatively straight, only slightly curved. Penis oval, in ventral view with shallow and linear impression along midline, lateral sides with deep canaliculus, which has dorsal side much broader than ventral.

Variation. Body ♂♂ (n=7) length: 1.66–2.34 cm, width: 0.52–0.75 cm, length/width ratio: 3.08–3.19; ♀♀ (n=21): length: 1.83–2.76 cm, width: 0.59–0.92 cm, length/width ratio: 3.00–3.10. (Main specimens see Fig. 2 .) Dorsal colouration usually with distinct dark blue purple tint. Oval impressions on 2nd intercostal interval vary from moderately large to small or absent, and the number from 3, 2, 1 to 0 on one side. These features are usually positively correlated with body size. The elliptical elytral principal impression also varies in size and shape. One specimen ( Fig. 2J ) with elliptical principal impression and oval impression at apical third obviously connected. Structure of elytra and pronotum nearly constant. Female Ventrite V slightly notched at the tip ( Fig. 2D ).

Aedeagus (n=5) length: 4.18–5.35 mm, width: 0.88–1.08 mm, length/width ratio: 4.75–5.12. Small-sized specimens may have some variation in the parameres, penis nearly constant ( Fig. 5B ).

Biology and adult host plant. Adults eat leaves of Toona ciliata and can be found on the tree frequently.

Etymology. The specific name is after the type locality.

Distribution. China (Hainan Island).

Remarks. The characters of this new species seem to be between Chrysodema sonnerati species-group and Chrysodema aurostriata species-group (sensu Frank & Sekerka, 2020). The following two characters of this new species are similar to the former species-group: 1) The principal impressions on pronotum distinct, longitudinal, narrowed; 2) elytra without obvious transverse impressions but with large elliptical principal impressions. However, with slightly but distinctly convex costae and wide longitudinal intercostal intervals on elytra are more similar to the latter species-group. Since the new species is most similar to C. (C.) lewisii nakatai at first glance, we assign it to the Chrysodema sonnerati species-group.

Although many species of genus Chrysodema have been sold as ornamental beetles in large quantities for years, only a limited number of host plants have been discovered, such as Terminalia catappa (Family: Combretaceae ), Machilus thunbergii (Family: Lauraceae ), Castanopsis sieboldii sieboldii , Lithocarpus edulis , Quercus phillyreoides (Family: Fagaceae ), Mallotus japonicus (Family: Euphorbiaceae ) and Casuarina equisetifolia (larva, Family: Casuarinaceae )( Ohmomo & Fukutomi, 2013; Ong & Hattori, 2019). The adult host plant of this new species is a newly recorded family and genus for Chrysodema .

Differential diagnosis. This new species presents several diagnostic characters which allow it to be easily separated from other related species: 1) Punctation on each elytron always regular, forms 4 wide longitudinal intercostal intervals, 2) most specimens with large elliptical principal impression protruding from lateral impression to 3rd intercostal interval at apical third of each elytron, 3) most specimens with oval impression in 2nd intercostal interval of each elytron at basal third, 4) apices of parameres subtruncate, inner tip relatively rounded, lateral margin of parameres relatively straight, only a slight curvature; Penis oval, no obvious widening.

Figures

FIGURE 1. Chrysodema, habitus (Scale = 10 mm): A–C—C. (C.) hainanensis sp. nov. (holotype); D–F—C. (C.) lewisii nakatai Frank & Sekerka, 2020 (female from New Taipei, Taiwan); G–I—C. (C.) lewisii lewisii Saunders, 1873 (male from Okinawa, Japan). A, D, G—dorsal view; B, E, H—ventral view; C, F, I—lateral view.

FIGURE 2. Chrysodema (Chrysodema) hainanensis sp. nov., habitus (Scale in A, B, E–J = 10 mm; in C, D = 1 mm): A, B—variable of males; C—male ventrite V; D—female ventrite V; E–G—female habitus; H–J—variable of females. A, B, E, H–J—dorsal view; C, D, F—ventral view; G—lateral view.

FIGURE 5. Chrysodema, genitalia and terminal abdominal segments (Scale in A–F, I, L, O, R = 1 mm; Scale in G, H, J, K, M, N, P, Q, S, T= 0.2 mm): A—C. (C.) hainanensis sp. nov. (holotype); B—C. (C.) hainanensis sp. nov. (paratype, small-sized); C—C. (C.) lewisii lewisii Saunders, 1873 (Okinawa, Japan); D—C. (P.) dalmanni (Mannerheim, 1837) (Ludao Island, Taiwan); E—C. (P.) yasumatsui Kurosawa, 1954 (Lanyu Island, Taiwan); F–H—C. (C.) hainanensis sp. nov. (paratype); I–K—C. (C.) lewisii nakatai Frank & Sekerka, 2020 (New Taipei, Taiwan); L–T—C. (C.) tonkinea Kerremans, 1909 (variability of ovipositor and terminal abdominal segments; all from Nanning, Guangxi).A–E—parameres (left) and penis (right); F, I, L, O, R—oviposi- tor; G, J, M, P, S—female tergite IX; H, K, N, Q, T—female tergite VIII.

FIGURE 6. Host plant and habits of Chrysodema (Chrysodema) hainanensis sp. nov. (Mt. Lizhiling, Sanya, Hainan):A—Toona ciliata in the wild; B—marginal feedings on the leaves of T. ciliata by C. (C.) hainanensis sp. nov.; C— natural habitat; D—lateral view of living individual; E—dorsal view of living individual.