Prothyma (Symplecthyma) coerulea Horn, 1920

Anichtchenko, Alexander & Wiesner, Jürgen, 2023, Philippine species of the genus Prothyma Hope, 1838 (Coleoptera: Cicindelidae). Part 2. Subgenus Symplecthyma Rivalier, 1964, Zootaxa 5357 (1), pp. 71-99 : 79-82

Prothyma (Symplecthyma) coerulea Horn, 1920 ( Figs 4 , 5 )

Prothyma heteromallicollis coerulea Horn 1920: 16 , 17. Type locality: “Mindanao: Dapitan”.

Prothyma lucidicollis coerulea: Horn 1926: 100 ; Horn 1934: 145, f. 5.

Prothyma (Symplecthyma) coerulea: Rivalier 1964: 160 , f. 17b, 161; Wiesner 1980: 124; Wiesner 1992: 59; Cabras, Cabigas & Wiesner 2016: 193; Dheurle & Colas 2018: 129, f. 5; Wiesner 2020: 139.

Type material. Lectotype (designed here) male: “Dapitan / Mindanao / Baker”, “Type / W. Horn”, “Snytypus [red label]”, “DEI Münchenberg / Col-14525 [green label]”, SDEI Coleoptera / # 301932”, “ LECTOTYPE / Prothyma / ( Symplecthyma ) / coerulea W. Horn, 1920 / design. Anichtchenko & Wiesner 2023 [printed, red]” [8.605538, 123.425010] ( SDEI). Paralectotypes, 1 male: idem, but “DEI Münchenberg / Col-14526 [green label]” ( SDEI); 1 female: “Dapitan / Mindanao / Baker”, “Type / W. Horn”, “Snytypus [red label]”, “coerulea / var. mihi ”, “DEI Münchenberg / Col-14524 [green label]”, SDEI Coleoptera / # 301933”, All specimens with label “ PARALECTOTYPE / Prothyma / ( Symplecthyma ) / coerulea W. Horn, 1920 / design. Anichtchenko & Wiesner 2023 [printed, red]”.

Diagnosis. Easily distinguished from other species by the following combination of characters:small size; narrow, slender body; upper side of body with microreticulation giving matte appearance; elytra with uniform punctures; dorsally with a uniform coloration, usually completely blue-violet in nominative subspecies, or in subspecies P. coerulea opacosericea comb. nov. head and pronotum blue-violet with copper elytra, rarely completely copper.

Re-description. Size: TL (without labrum) 8.4–10 mm (mean = 9.2 mm; n = 8). Body slender. Dorsally color varies from uniformly blue or violet to uniformly red, sometimes head and pronotum blue and elytra red with blue humeral stripes ( Figs 4a–c ).

Head: slightly wider than elytra (mean EW/HW = 0.9) ( Fig. 5 ). Dorsally color uniformly deep blue; sometimes with copper reflections, or rarely copper with blue reflections;clypeus deep blue; surface glabrous, with two setigerous punctures next to eye, one along frontal margin and one dorsally at center; longitudinal striae on orbital plates strong, straight, and parallel, becoming weakly undulating in the middle between eyes; rugae on the neck transverse and moderately undulate; striae becoming weak on genae and clypeus. Labrum golden-green, laterally with red and purple reflections. Labrum of male ( Fig. 4d ) wider than long (mean LW/LL = 1.37); with four setae located near the margin, two lateral and two apical; with two obtuse anterolateral teeth and two small teeth at the anteromedian lobe, intermediate space slightly convex. Labrum of female ( Fig. 4e ) slightly transverse (mean LW/LL = 1.1); with two setae located near the lateral margins and two setae centrally, between midline and lateral margins in anterior fourth; with two blunt anterolateral teeth and two inward directed, curved teeth on the anterior margin at the anteromedian lobe, intermediate space with a long and slightly downturned triangular tooth. Mandibles light brownish, with four dark brown teeth. Labial and maxillary palpi testaceous, the last segment of both brown. Antennae slender, reaching posteriorly to the middle of the elytra in the male, shorter in the females; scape testaceous with brown base, antennomeres 2–4 testaceous or sometimes with brownish apices; scape with one apical seta, the following three antennomeres almost glabrous; antennomeres 5–11 dark brown, matte, finely, and evenly pubescent.

Thorax: pronotum elongate (mean PW/PL = 0.82); sides subparallel between the transverse constrictions; glabrous; transverse wrinkles dense and coarsely rugate; evenly deep blue, sometimes with green reflections along midline; sternae and episternae glabrous.

Elytra: ( Figs 4a–c ) elongate, more than twice as long as wide (mean EL/EW = 2.2–2.3), parallel-sided, with a dorsally flattened basal hump, dorsal surface slightly microreticulated, matte; uniformly blue or violet sometimes coppery red with faint blue reflections in anterior half and laterally; testaceous elytral maculation in males consists of humeral, lateromedial, and preapical spots; the humeral spot is small and narrow, located in anterior margin of the humeri; the lateromedial spot is short and triangular, sometimes narrow or almost absent; the preapical spot varies from relatively large and rounded to a narrow and short stripe; in females humeral spot absent. Elytra uniformly sculptured laterally and on the disc. Punctures deeply impressed and rounded, slightly transverse in apical part; never squamiform. Apical margin minutely serrate, distinctly rounded and restricted towards middle suture, with a minute sutural spine. Epipleurae black.

Ventral aspect: bluish-violet; sternae and episternae glabrous; pro- and mesocoxa testaceous, metacoxa violet with testaceous apex; trochanter glabrous, pro- and mesocoxa with 4–5 setae, metacoxa bisetose; femur, tibia, and tarsi setose; Leg coloration varies between specimens from the same population, from completely yellow with only last tarsomeres slightly darker to dark brown with metallic blue luster and only base of femora yellow. Coxa, and basal half of femur relatively testaceous, remaining segments of legs brownish, with or without metallic luster. Protarsomeres 2–3 in males laterally and ventrally covered by long white setae.

Aedeagus: ( Figs 4f–h ) in overall appearance very similar with P. aeneoparva , i.e., median lobe relatively short, in lateral view abruptly widened from the base to the middle and tapering again towards the short apex with hook on the tip. Apical hook with sharp or blunt tooth. Ventral side of median lobe, just behind the middle towards to apex, with rounded protrusion, in which the coil of spiral sclerite is situated. The spiral sclerite of endophallus at the base has three complete coils.

Distribution. The nominative subspecies known from Mindanao: Dapitan ( Horn 1920: 16). The subspecies P. coerulea opacosericea Horn, 1929 is known from SE Luzon ( Map 1 ).

Figures

MAP 1. Distribution of species of Prothyma (Symplecthyma).

FIGURE 4. Prothyma (Symplecthyma) coerulea Horn, 1920. a) Dorsal habitus Lectotype, male. b) Dorsal habitus Holotype P. bella Dheurle & Colas, 2018, syn. nov. = P. coerulea opacosericea Horn, 1929 comb. nov.; c) Dorsal habitus Lectotype, male P. coerulea opacosericea Horn, 1929 comb. nov. Scale = 5 mm. d–e Labrum P. coerulea s.str. ST. Scale = 1 mm.: d) Male, e) Female. f–h. Aedeagus. Scale = 1 mm. f) P. coerulea Lectotype. g) Lectotype, male P. coerulea opacosericea Horn, 1929 comb. nov.. h) Holotype P. bella Dheurle & Colas, 2018, syn. nov. = P. coerulea opacosericea Horn, 1929 comb. nov.

FIGURE 5. Head of Prothyma (Symplecthyma) coerulea Horn, 1920. a) P. coerulea s.str. b) P. bella Dheurle & Colas, 2018, syn. nov., c) P. coerulea opacosericea Horn, 1929. Scale = 1 mm.