Gahaniella, Timberlake, 1926

Noyes, John Stuart, 2023, ENCYRTIDAE OF COSTA RICA (HYMENOPTERA: CHALCIDOIDEA), 4 Subfamily Encyrtinae: tribes Arrhenophagini, Habrolepidini, Cerapterocerini, Cheiloneurini, Trechnitini, Cercobelini, Polaszekiini, Protyndarichoidini, Gahaniellini and Syrphophagini (part), mainly primary parasitoids and hyperparasitoids of Coccoidea and Psylloidea (Hemiptera), Taxonomic Monographs on Neotropical Hymenoptera (Oxford, England) 2 (11), pp. 1-921 : 548-549

Genus GAHANIELLA Timberlake

Gahaniella Timberlake, 1926:23-26 . Type species: Gahaniella californica Timberlake , by original designation and monotypy.

Female. Length about 0.9-1.8mm.

Body generally dark metallic green with some coppery or purple areas; fore wing hyaline with pale yellow venation.

Head about 2X frontovertex or only slightly more; occipital margin sharp, carinate; vertex with a shiny bottomed depression along eye margin behind posterior ocellus; frontovertex with conspicuous punctate-reticulate sculpture of cell size about equal to diameter of eye face; scrobes shallow, weakly delimited dorsally and laterally; malar suture absent; antenna inserted about level with lower eye margin or slightly above, torulus separated from mouth margin by at least 1.5X its own length; scape short, about as long a malar space and about 3X as long as broad; funicle segments subequal in size, larger than pedicel, all with very conspicuous longitudinal sensilla which are about as long as segment; clava 3-segmented, sensory area minute, apex rounded; mouth narrow, about one-third head width; mandible with 1 tooth and a broad, slightly concave truncation; palp formula 4.3;

Thorax dorsally slightly convex; pronotum short, hardly visible behind head; mesoscutum with imbricate-reticulate sculpture; notaular lines absent; scutellum with strongly longitudinally elongate sculpture that is at least about as deep as that on mesoscutum; mesopleuron clearly separated from gaster by propodeum and hind coxa; mid tibial spur very slightly shorter than mid basitarsus; fore wing about 2.2X as long as broad; marginal vein about 2X as long as broad, about as long as stigmal vein, slightly longer than postmarginal vein; stigmal vein with only 3 campaniform sensilla at apex; parastigma not swollen; linea calva interrupted, sometimes closed; filum spinosum present, represented by only 2 or 3 modified setae; propodeum short, medially not more than 0.1X as long as scutellum, spiracles nearly touching anterior margin, about 10-15 silvery setae laterally.

Gaster about as long as thorax or a little shorter; paratergites absent; hypopygium not reaching more than half way along gaster and at least about 2.7X as broad as long, subrectangular, posterior margin fairly straight; syntergum slightly shorter than mid tibia to slightly longer, apex rounded or acute; ovipositor hidden or hardly exserted with the exserted part not more than about 0.3X mid tibial spur; gonostylus free, second valvifer with a distinct, short, leaf-like flange that overhangs the proximal part of the gonostylus.

Male. Length about 0.8-1.2mm. Generally very similar to female; funicle with segments about 1.5-2.0X as long as broad and clothed with whorls of long setae, the longest of which is about 3-3.5X as long as diameter of segments, setal socket unusually large; linear sensilla absent from 1 or 2 proximal segments and only about 0.5X as long as segment; phallobase slender, parameres present, slender, reaching about 0.7X to apex of digitus, with a single subapical seta and a basal seta; each digitus about 4.5X as long as wide, with an apical tooth and an apical bristle; aedeagus slender, nearly 8X as long as wide, with apex rounded and about 0.5X as long as mid tibia.

DISTRIBUTION. USA (Hawaii, Florida), Caribbean, Central and South America.

HOSTS. Recorded as parasitoids of various genera of Coccidae ( Hemiptera ) viz: Ceroplastes Gray , Coccus Linnaeus , Differococcus Granara de Willink , Milviscutulus Williams & Watson , Parasaissetia Takahashi , Parthenolecanium Šulc , Pulvinaria Targioni Tozzetti , Saissetia Deplanche , Toumeyella Cockerell (see below). Also recorded from Orthezia Bosc d’Antic (Homoptera: Ortheziidae ), and Planococcus Ferris ( Hemiptera : Pseudococcidae ) (see below) but these records probably need confirmation. There are also specimens reared from Crypticerya Cockerell ( Hemiptera : Monophlebidae ) in the NHMUK. It is likely that the species are hyperparasitoids (see Kerrich, 1953; Beardsley 1976).

COMMENTS. Females of Gahaniella can be recognised by the unique combination of the antenna placed relatively high on the head with a short scape, all funicle segments subquadrate, subequal and with conspicuous longitudinal sensilla, mandibles with one tooth and a broad truncation, pale fore wing venation and the ovipositor having short flat leaf-like extension at the apex of the second valvifer that overhangs the proximal part of the gonostylus.

IDENTIFICATION. Five species known, including one described as new below. For key to five previously described species see Trjapitzin, 2010; see also Timberlake (1926) and Kerrich (1953) for original descriptions of species.