Dentilla socotrana, Cascio & Romano & Grita, 2012

Cascio, Pietro Lo, Romano, Marcello & Grita, Flavia, 2012, New species and new records of mutillid wasps from the Socotra Archipelago (Hymenoptera: Mutillidae), Acta Entomologica Musei Nationalis Pragae 52, pp. 525-544 : 539-541

Dentilla socotrana sp. nov.

( Figs. 14–15 )

Type locality. Yemen, Socotra Island, Wadi Ayhaft, 12°36.5′N, 53°58.9′ E.

Type material. HOLOTYPE: ♀ ( NMPC), ‘ Socotra Is. ( YE), Wadi Ayhaft / 12°36.5′ N – 53°58.9′ E, 200 m / Jan Batelka leg., 7-8.xi.2010 ’. PARATYPES: ♀, ‘ Socotra: Homhil / 23-24.ii.2009 / leg. P. Lo Cascio & F.Grita’ ( PLFG) ; ♀, ‘ Yemen: Soqotra / Wadi Zerig, 8.iv.2008 / leg. B. Massa’ ( PLFG) .

Diagnosis. A female of Dentilla belonging to the group that includes species without spots of pubescence on T2, head and mesosoma red.

Holotype description. Body length: 5.6 mm. Habitus as in Fig. 15 . Head pale red, roundish, 1.14 broader than long and 0.9 narrower than pronotum. Surface of vertex shiny, with wide and irregularly lacunose punctuation, while on occipital area surface is matt and rugose and punctuation is smaller; genae finely punctate. Eyes oval, large, clearly protruding from head profile and strongly convex; maximum orbital diameter 0.6 of interocular distance; ratio between maximum and minimum orbital diameter 1: 0.69. Clypeus with prominent upper carina, clearly visible from above, ending in shiny basal tubercle. Mandibles ferruginous, weakly curved, darkish in apical half. Antennae entirely pale reddish, with curved scapes.

Mesosoma pale red, subrectangular, 1.14 longer than broad; pronotum just slightly arched, with sharp angles, less rounded and evanescent than posterior ones; lateral margins straight. Surface shiny, with punctuation larger and denser than head; in posterior half, interpuctual spaces very small but protruding in jagged denticles, aligned in arcuate rows parallel to back edge. Scutellar scale large and rounded. Pleurae with slightly rugose surface on mesopleural area. Propodeum feebly arched, without a distinct angle between propodeal and dorsal surface of mesosoma.

Legs including calcaria pale red, without salient characteristics.

Metasoma in holotype has lost the original black colour (see Variability) and became brown due to permanence in alcohol; metasoma 1.30 broader than mesosoma on its maximum width. T1 0.34 narrower than T2. Surface of T2 sparsely and finely punctate, dorsally with variolate punctures that laterally are larger, denser, and sometime confluent. Pygidial area as in Fig. 14 .

Pubescence on head yellowish, with recumbent and backward-facing short setae mostly on vertex; erect setae uniformly occurring, longer ones close to eyes and on occipital side; shorter erect setae occur also on clypeal margin and around upper carina, as well as on scapes, pedicels and F1, while all following flagellomeres are just clothed by short pubescence. Mesosoma dorsally covered with recumbent pubescence, with long erect setae on lateral and posterior margins, shorter setae occur on dorsum and on pronotal margin. T2 with long erect scattered yellowish setae and black recumbent setae, sparsely covering surface; posterior margin covered by continuous yellowish-whitish fringe with short and recumbent setae, just slightly forward extended in middle. Pubescence of T3–T5 mixed between long erect and short recumbent yellowish-whitish setae. Felt lines golden, 1.35 longer than their distance from posterior margin of T2.

Male. Unknown (see Remarks).

Variability. Length range of paratypes 5.5–5.6 mm. Head 1.09–1.19 broader than long and 0.87–0.91 narrower than pronotum. There are no substantial differences from the holotype, except for the colour of metasoma, which is black, and for the occurrence of long erect setae also on legs.

Differential diagnosis. Dentilla socotrana sp. nov. is morphologically comparable only with D. arabica ( Hammer, 1962) , originally described from continental Yemen as Smicromyrme ( HAMMER 1962) and recently placed in Dentilla by LELEJ & HARTEN (2006). After the examination of a specimen of D. arabica kept at ZMAN (labelled ‘ Yemen, Wadi Bana / 24.X.1992 / A. van Harten’, det. A. Lelej), we can exclude with certainty the identicality between the new and the latter species, which differs in the following features: larger eyes, both in relation to the head size and in maximum orbital length; clypeus less pronounced and protruding; head in a lateral view truncated forward (more round-shaped in D. socotrana ); mesosoma slightly narrowed in the anterior margin; surface of mesosoma finely and densely punctate; scutellar scale small and evanescent; propodeum more clearly truncated, with concave propodeal face; T2 less globose and slightly flattened; small pubescent spot on basal fringe of T2; different streaks pattern on pygidial area ( Fig. 13 ).

Etymology. The specific epithet is based on the current name of the island where the species has been found.

Biological notes. Data from labels indicate a broad phenology for this species, extended at least from November to April, and a wide distribution on the island. One of the specimens was collected at Homhil (about 1000 m a.s.l.) in a stony area subject to intensive grazing. Other traits of its biology are still unknown.

Remarks. Dentilla socotrana sp. nov. is the only female belonging to this genus found at Socotra so far. Therefore, it cannot be excluded that it could represent the opposite sex of the above-described D. purcharti sp. nov. Since the faunistic knowledge of the Mutillidae of the study area is not exhaustive, however, further studies could reveal the occurrence of other species. Furthermore, as males and females of this family are highly dimorphic, it is strongly recommended to establish their proper association after a direct observation of mating pairs under natural conditions (see ROMANO 2004, MANLEY & PITTS 2007), rather than based on the assumption of their sympatry.

Figures

Figs. 7–14. 7 – Fore wing of Dentilla purcharti sp. nov. (holotype). Scale bar = 1 mm. 8–10 – Genitalia of D. purcharti sp. nov. (holotype) in dorsal, lateral and ventral view. Scale bar = 200 μm. 11 – Mandibles of D. ehrenbergi Lelej, 2006 (paratype). Scale bar = 200 μm. 12 – Mandibles of D. purcharti sp. nov. (paratype from Wadi Da’arho). Scale bar = 200 μm. 13 – Pygidial plate of D. arabica (Hammer, 1962). Scale bar = 200 μm. 14 – Pygidial plate of D. socotrana sp. nov. (holotype). Scale bar = 200 μm.

Fig. 15. Habitus of Dentilla socotrana sp. nov. (holotype) in dorsal and lateral view. Scale bar = 1 mm.