Vanuatubasis malekulana (Kimmins, 1936)

Saxton, Natalie A., Marinov, Milen G. & Bybee, Seth M., 2022, Revision of Vanuatubasis Ober & Staniczek, 2009 (Odonata, Coenagrionidae), with description of seven new species, ZooKeys 1128, pp. 129-169 : 129

Vanuatubasis malekulana (Kimmins, 1936)

Figs 7 , 20E , 21F

Neosbasis malekulana Kimmins, 1936: 72-73; Ober and Staniczek 2009: 492-495.

Remark.

Vanuatubasis malekulana was known by males only. Here we tentatively assign and describe the female.

Material examined.

Holotype (1 ♂ NHM). "Holo- | type" "New Hebrides: | Malekula, | Ounua. | Mar.and Apl. 1929 | Miss L.E. Cheesman. | B.M.1929-343." “331.” "NESOBASIS | malekulana | ♂ Holotype sp.n. | det. D.E.Kimmins. " Additional material (2 ♂♂ BYU). " VANUATU: Malekula Is: | Litslits, -16.1459 | 167.465, 18, 24.v.2018, | coll. S. Bybee and G. Powell " .

Paratypes (2 ♂♂ NHM). "Para- | type" " New Hebrides: | Malekula , | ounua. | Feb.1929. | Miss L.E.Cheesman. | B.M.1929-234." “231.” "NESOBASIS | malekulana | ♂ sp.n. | det. D.E.Kimmins. " .

Description of female.

Head: Labrium overall pale beige; labrum pale green with brown latero-posterior edges and a small, slightly indented medial pale spot at posterior edge; anteclypeus, genae, and mandibles (expect for reddish tips) pale green; postclypeus green with faint brown maculation medially; frons pale green, turning black posteriorly; scapes, pedicels, and flagella dark brown; vertex of head black, back of head pale green; three pale ocelli with small green patch apical of the median ocellus; eyes green.

Thorax: Prothorax dorsally black; laterally green; pronotum black medially with green edges, latero-posterior corners rounded to acute angles and weakly explanate, mid-line obviously indented across the pronotum, hind lobe with raised ridge that is curved outward medially, and extends to a sharp, acute point that protrudes posteriorly; mesostigmal plate black with green lateral edges, internal margins raised and protruding posteriorly. Pterothorax with black carina; laterally mesepisternum with black stripe reaching the dorsal carina and extending more than 3/4 of the mesepisternum, dark green on latter 1/4 of mesepisternum except for short brown strip at posterior edge of mesopleural suture; mesepimeron overall pale green with hints of yellow; metepisternum overall green with short, brown line located on metapleural suture near the base of the wings; mesinfraepisternum pale green to yellow; metepimeron pale green, with beige anterior portion; coxae and trochanters beige, femora dorsally dark brown and ventrally beige with black spines; tibiae pale brown with slightly darker, and smaller, spines than that of the femora; tarsi beige with dark brown edges and small, dense spines; pale brown tarsal claws that darken apically to reddish tips, claws with a small tooth located on the basal 1/4 of their length.

Wings: Hyaline with dark brown; pterostigma dark brown and rhombus-shaped, darkest on the edges; CuP halfway between antenodals in both wings; arculus just distal of second antenodal crossvein in both wings; discoidal cells unequal with FW dorsal edge being 1/2 as long as HW. Nodal index: 12/2-2/11 in FW and 10/2-2/9 in HW.

Abdomen: Overall pale green to yellow with black dorsal stripe from S1-S8 and lightening towards the edges, with pale brown setae; S1 and S2 green laterally; S3-S8 yellow laterally; S9 with pale blue dorsal stripe; S10 pale blue; Ovipositor overall beige, with darker serrated ventral edge; stylus with rounded edges, pale brown and lightening apically; gonapophysis reddish brown with slightly serrated dorsal edge. Cerci roughly triangular, brown, and narrowing to a rounded apex, dorsal and ventral edge straight.

Measurements (mm): total length 34-35 mm, abdomen 24-28 mm, HW 21-22 mm (n = 3).

Diagnosis.

Male. Vanuatubasis malekulana can be distinguished from all other Vanuatubasis , by the dorso-posterior corner of the mesostigmal plate raised in an auricle, lack of dark color on the metepimeron. Female. Females of V. malekulana can be distinguished by the dorsal, black area on S9 having an almost straight posterior edge, and having distinctly raised dorso-posterior corners of the mesostigmal plate in an auricle.

Variation.

Male. Postclypeal maculation sometimes extending to posterior edge of postclypeus; internal projects of cerci vary from rounded to more pointed; variable extent to which internal margins of mesostigmal plates are raised; dorsal patch on S9 variable in shape and ranging in color from cream to blue. Female. Postclypeal maculation variable in extent; sometimes having small, brown maculation on the mesinfraepisternum.

Distribution.

Malekula, Vanuatu.

Notes.

The male of this species was recently treated in Ober and Staniczek (2009). This species is the most variable within the genus with regional differences in size and coloration that do not represent any consistent structural differences. The female is tentatively associated here as variation among the males makes it difficult to determine species limits. Future work may lead to additional new species.

Figures

Figure 7. Vanuatubasis malekulana (♂ BYU) A dorsal thorax B lateral terminalia C dorsal terminalia D lateral habitus V. malekulana (♀ BYU) E dorsal thorax F lateral terminalia. Scale bars: 0.5 mm.

Figure 20. Male dorso-posterior and dorsal terminalia of A V. bidens B V. evelynae C V. insularivorum D V. kapularum E V. malekulana F V. nunggoli G V. santoensis.

Figure 21. Female face and dorsal terminalia of A V. bidens B V. discontinua C V. evelynae D V. insularivorum E V. kapularum F V. malekulana G V. nunggoli H V. rhomboides I V. santoensis J V. xanthochroa.