Research Article |
Corresponding author: Stefan Schmidt ( schmidt.s@snsb.de ) Academic editor: Hannes Baur
© 2015 Chiun Cheng Ko, Yuan Tung Shih, Stefan Schmidt, Andrew Polaszek.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Cheng Ko C, Shih YT, Schmidt S, Polaszek A (2015) A new species of Encarsia (Hymenoptera, Aphelinidae) developing on ficus whitefly Singhiella simplex (Hemiptera, Aleyrodidae) in China and Taiwan. Journal of Hymenoptera Research 46: 85-90. https://doi.org/10.3897/JHR.46.5155
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Encarsia singhiellae Polaszek & Shih, sp. n., is described and illustrated. It is known so far from Taiwanand China. All specimens were reared from the ficus, or fig, whitefly Singhiella simplex (Singh), an Asian species recently attaining pest status in California, Colombia, and Florida.
Parasitoid, invasive species, potential biocontrol agent
The ficus or fig whitefly Singhiella simplex was described from India (
There are three published records of parasitoids of this species, all apparently from Florida.
FAFU Fujian Agriculture and Forestry University, Fuzhou, CHINA.
NHM Natural History Museum, London, UK.
NTU National Taiwan University, Taipei, TAIWAN.
A single series of reared specimens collected in September 2010 by the second author (YTS) was studied in detail for taxonomically useful morphological characters by the second and fourth (AP) authors. A single specimen reared one month later from the same host from mainland China proved to be morphologically identical. DNA was successfully sequenced from four individuals from the original sample, using the protocol described in detail by
Colour: Head yellow, antenna yellow, slightly darker towards apex. Mesosoma yellow except following light brown: pronotum, posterior margin of mesoscutum, anterior margin of scutellum, axillae and sides of propodeum. Metasoma yellow except T5 dark brown in strong contrast. Base of T1, and T4, infuscate centrally. Fore wing slightly infuscate below marginal vein. Legs yellow.
Morphology: Mandibles each with three small teeth. Stemmaticum with five robust setae and reticulate surface sculpture. Antennal formula 1,1,4,2. F1, F2, F3 approximately equal in length, with any of the three antennomeres the longest in different specimens. Pedicel with two robust setae dorsally. F4 0.9 times F1 (0.85 in holotype); F5 0.7–0.9× F1 (0.73 in HT); F6 0.8–1.0times F1 (0.9 in HT); funicle length 2.5times clava length (2.3 in HT). F1–F6 with the following numbers of multiporous plate sensilla: F1:0; F2:2; F3:2; F4:3; F5:3 F6:3. Mid lobe of mesoscutum with 4 or 5 pairs of setae, 1 lateral pair and 3–4 centrally (one central seta unpaired in holotype); side lobes with three setae. Scutellar sensilla closely placed, separated by less than the maximum width of one sensillum. Distance between posterior pair of scutellar setae 2 times distance between posterior pair (2.1 times in HT). Fore wing 2.8 times maximum width of disc (2.84 in HT). Marginal fringe 0.26 times maximum width of disc (0.25 in HT). Submarginal vein with 3 setae; marginal vein anteriorly with 7–9 setae (8+9 in HT). Basal cell with 9–15 setae (11+12 in HT). Tarsal formula 5-5-5. Mid tibial spur 0.56 times corresponding basitarsus. Mid tibia with a prominent spine-like seta apically. Metasomal tergites with the following numbers of setae: T1: 0, T2: 2, T3: 2, T4: 2, T5: 4, T6: 4, T7: 4. Ovipositor 1.2 times mid tibia; 2nd valvifers 3.8 times third valvulae (3.7 in HT).
Unknown.
Holotype female (NHM) on slide, labelled “TAIWAN: Taoyuan, Kuanyin (25.034°N, 121.113°E), 07 July 2011, ex Singhiella simplex on Ficus microcarpa Y.T. Shih col. Holotype Encarsia singhiellae Shih & Polaszek”; paratypes: 9 females, same data as holotype (NHM, NTU). CHINA: Fujian, Xiamen (24.481°N, 118.089°E), 6.x.2010 ex Singhiella simplex on Ficus microcarpa, J Huang, A Polaszek, Z-H Wang col. (1 female, FAFU).
The close proximity of the scutellar sensilla, coupled with three setae on the submarginal vein might suggest placement of the new species in the E. strenua group, but the shape of the stigma vein indicates that this placement would be incorrect. E. strenua group species have a distinct constriction between the marginal and stigmal veins. DNA analysis of the 28S D2 region places E. singhiellae sp. n. far away from the monophyletic E. strenua group, in an assemblage that includes E. tricolor Foerster, E. tachii (Polaszek & Hayat), and E. mineoi Viggiani (S. Schmidt, unpublished data). Encarsia singhiellae is therefore currently unplaced with respect to any known species group of Encarsia. The sequence has been deposited in GenBank under accession number KT279403.
In the key to Chinese Encarsia species (
Singhiella simplex (Singh) (Hemiptera: Aleyrodidae).
Encarsia singhiellae sp. n. is not closely related to any known Encarsia species, either in the Oriental Region or elsewhere. It has several unusual characters as follows: antenna with two robust setae on the pedicel, and F1 having distinct sculpture; anterior apex of mid tibia with one distinct long spine-like seta. The following character states place the new species in the genus Encarsia: fore and hind tarsi five-segmented, eight antennomeres (excluding radicle), scutellum with two pairs of setae, marginal vein longer than submarginal vein, stigmal vein very short and postmarginal vein absent.
It is the first recorded parasitoid of Singhiella simplex in Asia, and appears to show a high degree of host specificity, as there are no host records from other whitefly species. The species is currently only known from the type locality.
This study was funded by the Taiwan Ministry of Science and Technology (Project No. 102-2628-B-002-019-MY3 to CCK and YTS). Field work in China by AP was facilitated by a grant from the Chinese Academy of Sciences to Prof Huang Jian, Fujian Agricultural and Forestry University. We are grateful to the following for useful comments on earlier versions of the MS: John Heraty, John Huber, John Noyes, JimWoolley.