Chrysodema (Gelaeus) walkeri subsp. walkeri walkeri (Waterhouse 1892
Creators: name: Frank, David
name: Sekerka, Lukáš
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Buprestidae
Chrysodema
Chrysodema walkeri
Chrysodema (gelaeus) walkeri walkeri (waterhouse, 1892)

description: Chrysodema (Gelaeus) walkeri walkeri (Waterhouse, 1892)
(Figs 24–26, 62)
Pseudochrysodema (?) Walkeri Waterhouse, 1892: 411 (original description).
Chrysodema Walkeri: KERREMANS (1903): 76 (catalogue); KUROSAWA (1982): 190 (noted as type species of Gelaeus).
Gelaeus Walkeri: WATERHOUSE (1905): 584 (noted); OBENBERGER (1926): 129 (catalogue); THÉRY (1935): 248 (key, catalogue); VOLKOVITSH (2001): 46 (noted); BELLAMY (2003): 35 (catalogue).
Chrysodema (Gelaeus) Walkeri: KERREMANS (1909): 509 (key), 510 (redescription, incl. colour Fig. 5, Pl. 22); HOŁYŃSKI (1994): 71 (noted as type species of Gelaeus in key to subgenera); LANDER (2003): Fig. 152 (colour photograph, not typical C. (G.) walkeri), BELLAMY (2008): 542 (catalogue).
Type locality. Indonesia, Maluku Province, Damar Island.
Type material examined. LECTOTYPE (present designation): ♀, ‘Damma I. [6.–11. xi.1891, J. J. Walker lgt.] / 92—20. [w, p] / Pseudochrysodema? / Walkeri / (Type) Waterh. [w, h] / Type [r, p] / 5766 [w, p]’ (BMNH). The specimen provided with an additional red printed label: ‘ LECTOTYPE ♀ / Chrysodema (Gelaeus) / walkeri walkeri / (WATERHOUSE, 1892) / David Frank & / Lukáš Sekerka des. 2016 [year handwritten]’.
Additional material examined. INDONESIA: MALUKU PROV.: Damar Island, 1 ♀ (NMPC), 1 ♀ (MNHN), 9 ♀♀ (MFNB), 2 ♀♀ (DFPC), 1 ♀ (RMNH), 1 ♂ 2 ♀♀ (RMNH, ex coll ZMAN), 6.–11. xi.1891, 1 ♀, J. J. Walker lgt. (BMNH).
Redescription of lectotype. Well preserved ♀ specimen missing only left fore ultimate tarsomere with claws. Length 31.75 mm, width 11.75 mm, length/width ratio: 2.70. Body strongly shiny.
Body generally bright green with golden and copper reflections, only tibiae with bluishgreen reflections (Figs 24–26). Elytra deep blue-violet, apex with purple reflections (Figs 24, 26). Tarsi brown with metallic green distal half of last tarsomere and claws.
Pronotum in general coarsely but sparsely punctate, only laterally punctures dense. Medial line well marked and impunctate. Medial impressions very weak, impressed only along medial line, basically present as rows of dense punctures, punctures slightly smaller than remaining ones on disc. Principal impressions present as narrow, moderately deep and sharply bordered line almost connected to basal impressions, with small dense punctures. Lateral impression shallow and punctate. Basal impressions large and triangular.
Elytra without lateral impressions, moderately punctate. Rows visible from base to apex, only apically weakly impressed, generally regularly arranged, and irregularly double in apical half. Punctures in rows V–VIII in middle third of elytra quite regular and sparse, forming distinct rows, not isolated groups; spaces much broader than puncture diameter, flat, not reticulate (Fig. 26). Intervals basally flat, not elevated, broad, approximately 4–6× as wide as rows of punctures, impunctate; apically and laterally somewhat elevated and punctate.
Mid femora in central part strongly shiny, sparsely punctate, punctures large, on sides punctures smaller and densely arranged.
Ventral side of body (Fig. 25) overall coarsely and quite densely punctate, only central parts of thoracic and abdominal ventrites sparsely punctate. Almost whole lateral sides of abdominal ventrite I densely and coarsely punctate, punctures small. Lateral sides of ventrite II mostly similarly punctate to ventrite I only basal line impunctate. Ventrites III–V largely smooth and sparsely punctate, dense punctation present as patch in lateroapical corners.
Variation. Body ♂ (n = 1) length: 31.25 mm, width: 11.00 mm, length/width ratio: 2.84; ♀♀ (n = 18) length: (26.50)29.25–35.00 mm, width: (9.50) 10.50–12.75 mm, length/width ratio: (2.66)2.71–2.85. Medial impressions in some specimens more impressed thus medial line looks elevated. Pronotum a variable tone of green but mostly with more or less distinct bluish tint. Principal impressions variable but always with more or less deeply impressed furrow. Two specimens have tarsi brown except for metallic claws. Remaining 17 studied specimens have last tarsomere metallic green. Aedeagus (Fig. 62) (n = 1) length: 8.11 mm, width 1.63 mm, length/width ratio: 4.97. Apex of parameres rounded. Penis elongate, subparallel-sided.
Differential diagnosis. The nominotypical subspecies can be easily distinguished from others by usually metallic coloured ultimate tarsomere (brown in other subspecies) and has smoothest elytra with sparsest punctation of all the subspecies. For additional characters see Table 1.
Chrysodema (G.) walkeri can be distinguished from other species of Gelaeus by dichromatic dorsal side of body with green pronotum and blue elytra. Similar colour combination is also present in C. (G.) cyanicollis (differing in uniformly metallic green tarsi) and in C. (G.) sara sp. nov. (differing in smooth surface of elytra without impressed rows or elevated intervals).
Distribution. Indonesia: Maluku Prov.: Damar Is.
Remarks. WATERHOUSE (1892) did not state how many specimens he had at his disposal when describing C. (G.) walkeri. We have located two specimens in BMNH with identical locality label ‘Damma I. / 92—20’, however, only one is labelled as type and has the original label handwritten by C. O. Waterhouse. The latter specimen perfectly matches the original description and has identical size to that of mentioned in the original description hence we designate this specimen a lectotype in order to fix identity of this taxon. We do not consider the other specimen as part of the type series as it has larger size than mentioned in the original description and the specimen does not bear any proof that it was studied by Waterhouse when describing C. (G.) walkeri. It is listed among Additional material examined with supplemented data according to the BMNH collection register. The number ‘[18]92—20’ refers to the following entry in the register: ‘458 coleoptera, various localities presented by the Lords of the Admiralty: collected by Mr J. J. Walker during the cruise of HMS ‘Penguin’; [Nos.] 5762–5988 (266 coleoptera) Damma Island Nov[ember] 6–11 [18]91’ (M. Barclay, pers. comm.).
AKIYAMA & OHMOMO (2000: plate 42) illustrated three forms of C. (G.) walkeri, however, they belong to C. (G.) walkeri nigriventris subsp. nov. (Figs 445-1, 445-2) and C. (G.) sara sp. nov. (Fig. 445-3).
description: Published as part of Frank, David & Sekerka, Lukáš, 2016, Revision of the subgenusGelaeus of Chrysodema (Coleoptera: Buprestidae: Chrysochroinae), pp. 671-719 in Acta Entomologica Musei Nationalis Pragae 56 (2) on pages 705-708, DOI: 10.5281/zenodo.5310800