Xenos hamiltoni Kathirithamby and Hughes

Kathirithamby, Jeyaraney & Hughes, David P., 2006, Description and biological notes of the first species of Xenos (Strepsiptera: Stylopidae) parasitic in Polistes carnifex F. (Hymenoptera: Vespidae) in Mexico, Zootaxa 1104, pp. 35-45 : 38-41

Xenos hamiltoni Kathirithamby and Hughes , new species (Figs. 1–3)

Type. Holotype ɗ: MEXICO, Estación de Biología “Los Tuxtlas” UNAM, 8 May 2002, (D. Hughes) (Colección Nacional de Insectos, Instituto de Biologia, Universidad Nacional Autonoma de Mexico, Mexico City).

Paratypes. ɗ: MEXICO, Estación de Biologia “Los Tuxtlas” UNAM, 8 May 2002, (D. P. Hughes) (Colección Nacional de Insectos, Instituto de Biologia, Universidad Nacional Autonoma de Mexico, Mexico City). ɗ: (same data as above), (D. P. Hughes) (Colección Nacional de Insectos, Instituto de Biologia, Universidad Nacional Autonoma de Mexico, as long as pro­ and mesothorax (scutum length, 0.32–0.35mm). Scutellum length: 0.42–0.45 mm. Postlumbium half the length of scutellum (length, 0.25–0.27 mm). Postnotum: twice as long as scutellum (length, 0.80–0.81 mm) ( Fig 3 A).

Wing: R1 is infuscated and interrupted in the middle; R2 arises a little after this and is as long as R3, R4 not reaching margin, R5 is short and arises below R4, MA, CuA1, CuA2 and CuP present and uninterrupted. Length of wing (along its longest length) = 2.77–2.83 mm ( Fig 3 C).

Length of IX th abdominal segment, 0.25–0.26 mm (Fig 1D).

Length of adeagus, 0.24–0.27 mm ( Fig 3 B).

Male cephalotheca. Length, 0.86–0.88 mm; width, 1.11–1.3 mm. The male cephalothecae extruded both between abdominal tergites and sternites (II–III, or III–IV or IV–V) ( Table 1 ).

Diagnosis. This is the nineteenth species of Xenos to be described from Mesoamerica and the first from Mexico. The new species is distinguished by short, pointed maxillary palpi which fits in a socket of the basal segment. The aedeagus, with pointed anterior and posterior heads and a hump on the dorsal posterior region, and the lengths of the pro­and mesothorax, are more than a third of the length of the metathorax.

The new species can be distinguished from X. zikani which has no basal maxilla segment, a long palpus which is 1/8 shorter than mandibles ( X. hamiltoni has a long basal segment and very short palpus), R3 arising close to R4 and R5 is absent in the wing (R3 not arising close to R4 and R5 present in X. hamiltoni ) and hump on dorsal posterior of aedeagus absent.

Etymology. The new species is named after the late Bill Hamilton FRS, who inspired us to study the behavioural ecology of the Strepsiptera family Stylopidae .

Figures

FIGURE 3. Xenos hamiltoni sp. n. A. Dorsal view of head and thorax. Scale bar = 0.5 mm. B. Aedeagus. Scale bar = 0.2 mm. C. Wing (right). Scale bar = 1.2 mm.

Tables

TABLE 1: Position of the extruded male pupae of Xenos hamiltoni sp. n. in the abdomen of the wasp Polistes carnifex F.

Number of male	pupae	Position on abdomen of Polistes
1		IInd & IIIrd tergites
2		IIIrd & IVth tergites
2		IVth & Vth tergites
1		IVth & Vth sternites
2		IIIrd & IVth sternites