Genus Soita Walker

Soita Walker 1865: 136 . Type species: psiloides Walker, by monotypy.

Phantasmiella Hendel, 1914: 87 (key); Hendel, 1915: 434 (desc.). Type species: Phantasmiella cylindrica Hendel, 1914, by original designation. Synonymy by Kagesawa (1998).

Xaniosternum Enderlein, 1920: 336 . Type species: Xaniosternum ophioneum Enderlein, 1920, by original designation. New synonymy

The genus Soita Walker was proposed by Walker (1865) for a single species, S. psiloides Walker, from Salawati, near New Guinea. Hardy (1974) added two species from the Philippines, S. baltazarae Hardy and S. ensifer Hardy, and provided a key to the three known species. Later, Hardy (1983) redescribed the female of S. psiloides and provided detailed figures of this species. Permkam and Hancock (1995) reviewed the diagnosis of this genus and recorded S. psiloides from Australia. Subsequently, the name Phantasmiella Hendel, 1914, was synonymized with Soita by Kagesawa (1998), who also provided a key to the four known species and studied the biology of S. cylindrica (Hendel) in detail. Norrbom and Hancock (2004) recorded this genus from New Caledonia.

Soita is characterized by the yellow slender body and wasp-like appearance, and head usually with 1 strong and strap-like orbital seta situated close to the middle of the frons, the abdomen usually having pairs of welldeveloped setae at least on the posterior margin of tergite 5. Head rounded in lateral view, with antenna longer than face and 1st flagellomere apically rounded (size and shape unknown in S. ophioneum); arista short plumose (unknown in S. ophioneum). Thorax yellow, lacking black marking, elongate, usually 2 times or more as long as wide. Scutum with complete transverse suture. Scutellum flat, shorter than wide, with 1–2 pairs of setae. Wing with veins R1, R4+5 and base of vein Cu1 with long, conspicuous setulae dorsally, R-M crossvein just beyond middle of cell dm; cell bcu with posterodistal lobe short and broad. Anatergite covered with long, fine setulae. Metathoracic postcoxal bridge broadly sclerotised. Mid tibia with 2 or 3 apical spurs, femora without rows of spines.

This genus generally resembles Ichneumonosoma, but differs in having the base of vein Cu1 setulose, 1 distinct and strap-like orbital seta, antenna longer than face, and most thoracic setae present (Permkam and Hancock, 1995). The host plants of S. cylindrica were recorded as Asclepiadaceae in Hokkaido and Honshu in Japan (Kagesawa, 1998). This is the only known biological information for this genus.

Xaniosternum was proposed as a monotypic genus by Enderlein (1920), who compared it with Phantasmiella Hendel, 1914, but not with Soita . Since then, no species have been added to Xaniosternum . However, Phantasmiella has been regarded as a synonym of Soita (Kagesawa 1998) . According to Enderlein, Xaniosternum differs from Phantasmiella mainly as follows: head not elongated, rounded; scutellum with only 1 pair of setae; mesonotum on anterior half densely covered with short, stiff, upright setulae (not with only one longitudinal row of such setae on each side); abdomen very long, slender, strongly compressed laterally; first tergite in lateral view about 2.5 times as long as high posteriorly; crossvein R-M somewhat proximal to middle of cell dm. However, all these characters are shared with Soita . Except for the katepisternum having 3 rows of short brown spines extending longitudinally along the anteroventral margin, an autapomorphy of X. ophioneum, we have found no significant difference between Xaniosternum and Soita . Xaniosternum also agrees well with the description of Soita by Hardy (1974), and our morphology based cladistic analysis supports it as a natural member of Soita (Figs. 151–153). Therefore, we here consider Xaniosternum a subjective junior synonym of Soita .

Here we also describe one additional new species, S. infuscata Chen & Norrbom, from New Caledonia. Consequently, Soita now includes six species, with known distributions in the Oriental (Philippines, China), Australasian (Indonesia, Papua New Guinea, New Caledonia, Australia), Palaearctic (Japan) and Afrotropical (Equatorial Guinea) Regions.