Plumarius gracilis Diez & Roig-Alsina

Diez, Patricia A. & Roig-Alsina, Arturo, 2016, Revision of Plumarius Philippi 1873 (Hymenoptera: Chrysidoidea, Plumariidae) from Argentina north of Patagonia, with description of eighteen new species, Zootaxa 4098 (3), pp. 442-470 : 465

Plumarius gracilis Diez & Roig-Alsina , sp. nov.

( Figs 18 A–E)

Diagnosis. This species falls in a group with the anterior ocellus above the supra-torular line and the marginal cell with the anterior margin short and the apex not narrowed. It is related to P. fidalgoi sp. nov. and P. ocellulatus sp. nov. but differs by the torulus closer to the lateral ocellus than to the clypeus. It is characterized by the short, medially narrowed marginal cell of the fore wing.

Description. Holotype, ♂. Body length: 5.9 mm (paratypes 3.0– 6.5 mm). Color. Light brown, head darker (except clypeus and mandible).

Head. 1.1 × as wide as high, in frontal view; narrower in dorsal view than width of scutum between tegulae (3.5:3.8). OOD 1.5 × diameter of lateral ocellus; POD 1.4 × OOD. Antennocular distance 0.5 × diameter of torulus; interantennal distance 4.7 × antenocular distance. Vertex reticulated, scarcely punctate between lateral ocelli (punctures separated by 2.5 × puncture diameter). Torulus closer to lateral ocellus than to clypeus (1.4:2.0). Lateral ocelli in frontal view below upper margin of head. Median ocellus above supra-torular line, ( Fig. 18 A). Genal carina absent. Length of area between preoccipital carina and suboral swelling shorter than length of suboral swelling (0.5:0.7); without median, longitudinal carina; low area of genal bridge close to mandibular articulation without carinae or punctures ( Fig. 18 B). Malar area equal than apical width of F1 (0.6:0.6); striate anteriorly. Supraclypeal area with weak lateral striae; weakly rounded in lateral view. Epistomal suture evident. Clypeus 1.4 × wider than high, with weak lateral striae; weakly rounded in lateral view ( Fig. 18 C). Proportion of lengths of maxillary palp, from base to apex: 8:7:12:15:14:14. Scape without swelling or projection. F1 4.0 × as long as its apical width, shorter than scape and pedicel combined (2.1:2.4).

Mesosoma . Area anterior to pronotal lobe smooth; pronotal lateral carina distinct, forming lower pocket. Notaulus weakly marked, as long as admedian line. Anterior surface of scutum scarcely punctate. Propleuron scarcely punctate, and mesopleuron without punctures. Metaposnotum with weak striae reaching posterior margin. Propodeum transverse; swollen behind spiracle, without carina anterior to spiracle. Fore wing: marginal cell with anterior margin 2.4 × as long as posterior margin, medially narrower ( Fig. 18 D); vein Rs3 subequal than Rs4 (3.0:3.1); vein M separated from cu-a by 3.5 × length of cu-a; discal cell rectangular. Protarsomere 1with two lateral spines. Length of mesotarsomere 1 shorter than metatarsomere 1 (2.3:3.5); inner metatibial spur 2.5 × as long as outer spur.

Metasoma. T7 triangular. Genitalia as in Fig. 18 E.

Examined material. Holotype, ♂. ARGENTINA, La Rioja, 1 ♂, Anguiñan (Chilecito), 16–30.VI.1969, col Willink, Terán, Stange (Malaise) ( IFML). Paratype: Catamarca, 1 ♂, 6 km N de Belen, 1240 m, 1–15.VI.1969, col Willink, Terán, Stange (malaise) ( MACN).

Distribution. Argentina (La Rioja, Catamarca).

Etymology. The specific name refers to the slender habitus of the species.

Figures

FIGURE 18. Plumarius gracilis sp. nov., ♂. A, Head, frontal view; B, Head, ventral view; C, Head, lateral view, D, Fore wing, marginal cell; E, Genital capsule, ventral view. Scale bars = 0.5 mm.