Diversinervus elegans Silvestri, 1915

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 : 492-494

Diversinervus elegans Silvestri

(Figs 1228-1233; Hab. E 177, G 178)

Diversinervus elegans Silvestri, 1915:304-305 . LectotypeE (here designated), Eritrea, DEZP, examined.

Cheiloneurus bicristatus Girault, 1915a:96 . Holotype E, Australia (Queensland), QMB, examined. Synonymy with elegans by Girault (1917a:37).

Diversinervus meridionalis Compere, 1931:237-239 . Holotype E, South Africa (Natal), USNM, not examined. Synonymy with elegans by Compere (1937:43).

Diversinervus intermedius Hayat, Alam & Agarwal, 1975:43 . Holotype E, India ( Puducherry), NHMUK, examined. Synonymy with elegans by Hayat (1989:279)

DIAGNOSIS. Female (overall length about 1.2-2.1mm): head orange; frontovertex and temple with a weak green and purple sheen; antenna (Fig. 1228) with scape orange, ventral margin dark brown; pedicel pale orange with a complete, dark brown, dorso-lateral stripe internally; F1-F4 slightly dusky, each with a complete, dark brown, dorso-lateral stripe internally; F5 slightly dusky pale orange, F6 pale orange; clava with basal segment pale orange, otherwise dark brown; thorax orange with posterior margin of pronotum white and translucent, propleuron ventrally brown, posterior one-third of mesoscutum metallic dark blue, mixed green and brassy and anterior margin of mesopleuron brown and posterior two-thirds slightly dusky; all coxae white, legs otherwise mainly white to pale orange but fore and mid tibiae each with a narrow, subbasal brown fascia, hind tibia with a broad, median orange-brown band and hind basitarsus apically dark brown; fore wing (Fig. 1232) mostly infuscate but hyaline towards base and at apex of venation; propodeum orange with a weak brassy lustre, side posteriorly with a metallic green and purple sheen; gaster generally slightly dusky orange, dorsally and laterally towards base with a conspicuous coppery purple, green and brassy sheen; gonostylus pale orange; head about 4-7X as wide as frontovertex, relatively wider in smaller specimens; ocelli forming an angle of about 45-55°; scrobes moderately deep and broadly ∩-shaped; antenna as in Fig. 1228, scape broadened and flattened, slightly more than 2X as long as broad, F1-F4 subequal, quadrate or slightly longer than broad, F5-F6 conspicuously larger and subquadrate, linear sensilla present only on F5-F6; clava slightly enlarged, about 1.5X as wide as F6 and nearly as long as F3-F6 combined, sutures slightly oblique, sensory area slightly enlarged extending about 0.3X along ventral margin of clava, apex slightly obliquely truncate; eye reaching occipital margin; inner eye margins weakly converging anteriorly; thorax (Fig. 1233) with pronotum clearly exposed behind head, in dorsal view about 0.8X as long as mesoscutum with a distinct median notch in posterior margin; sculpture of pronotum fairly shallow; mesoscutum with a distinct, median, anterior tuft of long black setae, scutellum with similar, subapical tuft; sculpture on mesoscutum mostly longitudinally elongate, polygonally reticulate and deeper than that on pronotum, but posterior metallic area with shallower, more rounded sculpture; axilla matt, with similar but slightly deeper sculpture than that on posterior part of mesoscutum, scutellum matt with elongate polygonally reticulate sculpture that is virtually arranged in whorls; fore wing about 2.7X as long as broad, with venation and setation as in Figs 1231, 1232; gaster with hypopygium (Fig. 1229) reaching about half way to apex; ovipositor (Fig. 1230) 1.3X as long as mid tibia, or 4.3X as long as gonostylus, slightly exserted, with the exserted part about 0.2X as long as mid tibial spur or less than 0.1X mid tibia. Male (length about 0.8-1.3mm): head generally metallic green often with a distinct purple sheen on occiput, lower face and gena; scape pale yellow to pale orange; pedicel pale orange, slightly dusky dorsally; flagellum dusky pale orange; pronotum and mesoscutum metallic green; scutellum metallic green with a slight purple sheen; prepectus pale yellow; mesopleuron metallic green with a strong purple sheen; legs pale yellow to very pale orange, hind tibia with a very faint, brown, subbasal ring; fore wing venation pale orange; propodeum dark purple-brown, side metallic green; gaster dark purple brown, basal tergite dull metallic green; head a little more than 2X as wide as frontovertex; ocelli forming an angle of about 90°; frontovertex with deep, fine, punctate-reticulate sculpture of mesh size slightly smaller than eye facet; scape slightly broadened, about 2.5X as broad as long; all funicle segments at least about 2X as long as broad and clothed with whorls of long setae that are about 3X as long as diameter of segments; mesoscutum and scutellum without any distinct tufts of setae; anterior one-third of mesoscutum with longitudinally elongate, polygonally reticulate sculpture, posterior two-thirds with polygonally reticulate sculpture forming rounded cells, these finer posteriorly; scutellum with slightly elongate, polygonally reticulate to striate sculpture, more or less arranged in whorls.

DISTRIBUTION. Virtually Cosmopolitan (tropical, subtropical and Mediterranean) ( Noyes, 2019). Newly recorded below also from Honduras, Costa Rica, Guadeloupe, Peru, Zimbabwe, Madagascar, Philippines, Papua New Guinea and Fiji (new records).

HOSTS. Recorded as a primary parasitoid of species of several genera of soft scales ( Hemiptera : Coccidae ) including Ceroplastes Gray , Coccus Linnaeus , Eulecanium Cockerell , Parasaissetia Takahashi , Pulvinaria Targioni Tozzetti and Saissetia Deplanche (Noyes, 2022) . Newly recorded below as a parasitoid of Ceroplastes rubens Maskell , Coccus alpinus De Lotto , Pulvinaria psidii Maskell and Saissetia miranda (Cockerell & Parrott) ( Hemiptera : Coccidae ) (new records). Also recorded below from Ferrisia virgata (Cockerell) ( Hemiptera : Pseudococcidae ) (new record) but this record is probably erroneous and requires confirmation.

BIOCONTROL. This species has been used in several biological control programmes where the target species are soft scale pests. During about 1935-1958 and again in 1971 it was introduced into New South Wales ( Australia) for the control of Ceroplastes destructor Newstead but did not become established upon that pest (Wilson, 1960; Greathead, 1971; Sands et al., 1986). It was introduced into California ( USA) in 1951, 1953 and 1964-1967 from Eritrea and Lebanon for the control of Coccus pseudomagnoliarum (Kuwana) and Parasaissetia nigra (Nietner) and eventually became established on P. nigra and contributed to partial control of that pest (Bartlett, 1966, Bartlett in Clausen, 1978; Lampson & Morse, 1992), Diversinervus elegans was also introduced into Israel from South Africa and from there into Spain, France, Italy, former Yugoslavia, Greece, Morocco and Argentina at various times in the 1970s for the control of P. nigra , and sometimes also Pulvinaria urbicola Cockerell , but without much success although it frequently became established (Panis & Maro, 1977; Paraskakis et al., 1980; Panis, 1981; Jourheuil, 1986; Argov & Rössler; 1988; Viggiani, 1988).

MATERIAL EXAMINED.

Type material. LECTOTYPE E (here designated): “Nefasit Saissetia oleae Sett 1914 ” “ Diversinervus elegans Silv. ”, card-mounted. Paralectotypes: 1E, “ Diversinervus elegans Silv. E Nefasit 13 Saisset”, slide-mounted; 1G “ Diversinervus elegans Silv. G Nefasit ”, slide-mounted. Type material in DEZP .

Non type material. EGYPT, 2E, Alexandria, Antonia, ex Ceroplastes rusci ? Lepidosaphes pomorum Conoteryx on mandarines, 10.vii.1929 (H. Priesner); 2E, Mahalla-El-Kubra, Coccus hesperidum , 16.x.1930 (H. Priesner); 1E, 1G, Lecanium longulum on Ficus altida , 22.ix.1969 (M. Hafez); 1E, 1G, Qalyubiya, Tukh, Site 1, ex Chloropulvinaria on Ficus sycamorus , 27.x.1990 (H.W. Browning); 1E, Qalyubiya, Banha Univ., ex Protopulvinaria psidii on Mangifera indica , 27.x.1990 (H.W. Browning). ERITREA, 1E, Asmara Plateau, ex Saissetia oleae , 5.viii.1930 (H. Compere). KENYA, 2E, Kiambu, ex Saissetia hemisphaerica , 23.iv.1930 (R.H. Le Pelley); 3E, 1G, Kiambu, ex Saissetia nigra Nietn. , 26.viii.1929 and 27.ii.1931 (R.H. Le Pelley); 3E, Kiambu, ex Saissetia oleae , 26.ii.1931 (R.H. Le Pelley); 4E, Forest, Kiambu, ex white waxy scale on coffee, 29.i.1985; 2E, Limuru, ex Ceroplastes destructor , 3.xii.1935 (H. Wilkinson); 1E, Limuru, ex C. destructor on coffee, ix.1935; 1E, Limuru, ex C. destructor , x-xii.1935; 1E, N. Kitito, Coccus alpinus on?coffee, 24.iv.1984 (C.I.E. 18015). ZIMBABWE, 1E, Salisbury, ix.1974 (A. Watsham) “Compared with Lectotype of D. elegans S.”. SOUTH AFRICA, 1E, Cape Prov., Mossel Bay, xii.1921 (R.E. Turner); 6E, 2G, Pretoria, Fountains, ex Coccus proteae on Protea caffra , viii.1961 (D.P. Annecke). MADAGASCAR, 1E, Betafo area SW Antantarivo, ex Parasaissetia nigra on Coffea , 11.iv.1989 (J.B.D. Robinson). INDIA, 2E, Karnataka, Hessaraghatta, ex Ferrisia virgata , iii.1989 (C.I.E. A20858). PHILIPPINES, 2E, 2G, Luzon, Ilagan, ex scale 86.80 on neem tree, 9.xii.1985 (M.J.W. Cock). FIJI, 4E, 1G, Suva, ex Lecanium on Colcus, xii.1931 (H.W. Simmonds); 2E, Suva, L296 and H296, ex Ceroplastes rubens Hibiscus , 23.xi.1938 (R.A. Lever). PAPUA NEW GUINEA, 1E, 1G, Central Province, Laloki A.R.S., on stem of Abelmoschus manihot , 11.ix.1996 (F.M. Dori). AUSTRALIA, 1E, Queensland, Sunnybank, ex olive scale on custard apple, 29.ix.1964 (J.H. Barrett); 1E, Queensland, 15km SE Nambour, 6.xi.1976 (Z. Boucek) “Compared with Lectotype of Cheil. bicristatus Gir. ”. USA, 3E, Florida, Fort de Soto, Pinellas, ex Saissetia miranda on Ficus aurea , 25.viii.1988 (F.D. Bennett); 4E, 2G, Florida, Miami, ex Saissetia on Ficus aurea , 30.iv.1987 (F.D. Bennett). GUADELUPE, 4E, 3G, Petit-Bourg, ex Coccidae , 5.ii.1990 (J. Etienne). HONDURAS, 2E, Paraiso, Jacaleapa. El Arenal, ex Coccidae , Salix humboldtiana vegetativo, 29.vii.1988 (J. Maresco). COSTA RICA, 1E, Heredia, Santo Domingo, INBio Parque, 1200m (error for 1100m), 19.ii.2001 (J.S. Noyes); 1E, Heredia, Santo Domingo, Parque Ecológico, 9°59’N 84°06’W, 1100m, 9.ii.2018 (J.S. Noyes); 1E, Puntarenas, PN Corcovado, Est. Agujas, Cerro Mueller, LS 521500 273200, xii.2001 - ii.2002 (J. Azofeifa). PERU, 2E, 1G, Lima, ex Saissetia hemisphaerica on Nerium oleander ,?1978 (O. Beingolea); 3E, 1G, Vitarte, CICIU, ex Saissetia nigra on Hibiscus rosa-sinensis , 21.ii.1978 (F. Nuñez). Material in NHMUK and MZUCR.

COMMENTS. I am designating a lectotype for elegans in order to ensure the current usage of the name. The specimen designated as lectotype of Diversinervus elegans has been labelled as such and is card-mounted and in good condition.