Vanuatubasis malekulana (Kimmins, 1936) Ober & Staniczek, 2009

Ober, Stefan V. & Staniczek, Arnold H., 2009, A new genus and species of coenagrionid damselflies (Insecta, Odonata, Zygoptera, Coenagrionidae) from Vanuatu, Zoosystema 31 (3), pp. 485-497 : 492-495

Vanuatubasis malekulana

( Kimmins, 1936) n. comb. ( Figs 4B, E, H, K ; 5A )

Nesobasis malekulana Kimmins, 1936: 72 , 73, figs 5, 6.

HOLOTYPE. — Vanuatu. Malampa Province, Malekula, Unua, III-IV.1929, leg. L. E. Cheesman, ♂ ( BMNH).

PARATYPES. — Vanuatu. Malampa Province, Malekula, Unua, II.1929, leg. L. E. Cheesman, 5 ♂♂ ( BMNH).

LABELS. — Holotype: Holo-/ type; New Hebrides:/ Malekula ,/ Ounua. / Mar. & Apl. 1929./ Miss L.E.Cheesman. / B.M.1929-343 .; 331.; NESOBASIS / malekulana/ ♂ sp.n./ Holotype / det.D.E.Kimmins. Paratypes: 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.

ADDITIONAL MATERIAL. — Not available.

DISTRIBUTION. — The species is only known from the type locality.

REDESCRIPTION OF THE HOLOTYPE

Preserved dry, pinned. In fairly good condition. Head, prothorax, left foreleg, right hind wing, and abdomen between segments 5, 6 and 7 glued.

Head

Labium pale fulvous; labrum dark blue-green, centrally more glaucous, with a semicircular, central dark brown spot at the basal margin; genae glaucous; anteclypeus greyish-brown; postclypeus blackish, laterally at the basal margin glaucous; frons below a semicircular line from the basal joints of the antennae to the postclypeus glaucous, above blackish; antennae at the basal joints glaucous, each scapus dark brown, anteriorly with a small glaucous stripe, pedicelli and flagella brown; vertex and occiput black except for a small brown spot in front of the median ocellus, diminutive postocular spots, composed of whitish pruinosity; back of head yellowish with a diagonal dark brown stripe; eyes dark brown.

Thorax

Prothorax black with a touch of a greenish metallic shimmer, laterally with slight bluish-white pruinosity; hind lobe of pronotum slightly raised, each side of upper rim sinusoidally shaped, medially forming a slightly rounded apex. The apex is connected with the prominent, lower ridge by a median keel ( Fig. 5A ). Synthorax: mesanepisternum with black median band, slightly greenish metallic, reaching the mesopleural suture in its hindmost fifth, but elsewhere separated from it by a brownish band, dorsal carina black; mesostigmal lamina slightly triangular, posterior margin proximally with a distinctive, rounded, slightly quadrangular protuberance, apex of lamina forming a slightly overhanging process ( Fig. 5A ); mesokatepisternum brownish to dark brown in the upper, pale greenish-grey in the lower half; mesepimeron pale greenish-grey with a dark brown to blackish triangular streak in the anterior part; metanepisternum pale greenish-grey,posteriorly with a small, elongate, dark brown to blackish spot at the metapleural suture; metakatepisternum light ochre with slight bluish-white pruinosity; metepimeron pale greenish-grey becoming creamy anteriorly; poststernum bluish-white pruinose, posterior margin black; sternum creamy to light brown with bluish-white pruinosity. Legs creamy, except outer surface of coxae, trochanteres, and femora, and inner median parts of tibiae, which are light to dark brown, especially the coxae with bluish-white pruinosity; spines dark brown.

Wings

Hyaline; venation brown; pterostigma pale brown, anteriorly with small pale margin, less than one cell long, rhomboidal; 13/12 postnodal crossveins in the left and 15/14 postnodal crossveins in the right forewing, 11/10 postnodal crossveins in the

A left and 12/11 postnodal crossveins in the right hind wing.

Abdomen

Segment 1 dorsally dark brown with bluish-white pruinosity, creamy and greenish-grey laterally; segment 2 dorsally blackish with slight greenish metallic shimmer, laterally greenish-grey and partly creamy; segments 3-6 brown to dark brown, getting paler laterally and pale ochre ventrally, brown colouration darker at the segment borders; segments 7-9 dark brown dorsally and at sides, ventrally reddish brown; segment 9 dorsally with a reddish-brown, centrally creamy bar, incurved anteriorly; segment 10 reddish-brown, dark brown dorsally, apical margin blackish, raised and excised at its centre. Superior anal appendages reddish-brown, short, in dorsal view crescent-shaped ( Fig. 4B, E ); in dorsocaudal view broad with convex upper margins and slightly concave lower margins, both laterally and medially converging to strong, posteriorly projected, rounded tips; in lateral view each tip appears triangular, the inner tip being higher and more protruded than the outer one ( Fig. 4H, K ). Inferior anal appendages reddish-brown, in dorsal view forceps-like, incurved, ending in a black tip which is directed inwards, about three times as long as the superior appendages ( Fig. 4B, E ); in lateral aspect broad at base, narrowing to an acute tip ( Fig. 4H, K ). Each inferior anal appendage bears basally on its inner side a strong, quadrate process fringed with hairs ( Fig. 4B, E ).

Measurements

Length of abdomen: c. 33 mm (not completely elongated), length of hind wings: 20.3 mm.

VARIATION

Only two of the five designated paratypes were available for study. One paratype nearly resembles the holotype in colouration, but face dull aquamarine and thorax somewhat paler with a smaller and less intensive brown spot on mesepimeron. The pruinosity is a little more intensive posteriorly. Abdominal segments 1 and 2 laterally glaucous, segments 9 and 10 dorsally creamy with reduced brown markings. Pronotal hind lobe less raised than in holotype and in other paratype. The other, somewhat smaller paratype is more intensively coloured: face aquamarine, thorax bluish-green with dark brown to blackish stripes on mesepimeron and metepimeron; mesokatepisternum and metakatepisternum dark brown. Brown colouration on abdominal segments 1 and 2 generally more developed, bluish-green colouration reduced, but brighter than in the other two specimens at hand. Only a small pale brown spot dorsally on segment 9.

Venation in both paratypes only slightly different from holotype: 12-15 postnodal crossveins in forewings, 11-13 postnodal crossveins in hind wings.

REMARKS

This species is only known from six males found at the type locality. All paratypes have identical label data (see above) (D. Goodger pers. comm.). Vanuatubasis malekulana n. comb. differs from V. bidens n. comb. in the wavy, less erected pronotal hind rigde and the strong, medio-posterior protuberance of the mesostigmal laminae. The shape of the superior anal appendages is crescent-like, the forcipate inferior anal appendages are more incurved than in V. bidens n. comb.

For differences to the closely related V. santoensis n. sp. see above.

Figures

FIG. 4. — A, D, G, J, Vanuatubasis bidens (Kimmins, 1958) n. comb., holotype,♂ (BMNH), anal appendages in dorsal and lateral view; B, E, H, K, V.malekulana (Kimmins,1936) n. comb.,holotype,♂ (BMNH),anal appendages in dorsal and lateral view;C, F, I, L, V.santoensis n. gen., n. sp., holotype, ♂ (SMNS: ODO 000242 K), anal appendages in dorsal and lateral views. Scale bars: 0.2 mm.

FIG. 5. — A, Vanuatubasis malekulana (Kimmins,1936) n. comb.,paratype,♂ (BMNH),hind lobe of pronotum and mesostigmal laminae in dorsal view; B, V. santoensis n. gen., n. sp., holotype, ♂ (SMNS: ODO 000242 K), hind lobe of pronotum and mesostigmal laminae in dorsal view. Scale bar: 0.2 mm