Molecular Ecology Resources (2012) 12, 791–796 doi: 10.1111/j.1755-0998.2012.03152.x
DNA barcoding of six Ceroplastes species (Hemiptera: Coccoidea: Coccidae) from China
JUN DENG,*† FANG YU,† TONG-XIN ZHANG,‡ HAO-YUAN HU,§ CHAO-DONG ZHU,† SAN-AN WU* and YAN-ZHOU ZHANG† *The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083, China, †Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China, ‡Ningbo Technology Extension Center for Forestry and Specialty Forest Products, Ningbo 315012, China, §College of Life Science, Anhui Normal University, Wuhu 241000, China
Abstract Ceroplastes Gray (wax scales) is one of the genera of Coccidae, most species of which are considered to be serious economic pests. However, identification of Ceroplastes species is always difficult owing to the shortage of easily distinguishable mor- phological characters. Mitochondrial cytochrome c oxidase I (COI) sequences (or DNA barcodes) and the D2 expansion seg- ments of the large subunit ribosomal RNA gene 28S were used for accurate identification of six Ceroplastes species (C. floridensis Comstock, C. japonicus Green, C. ceriferus (Fabricius), C. pseudoceriferus Green, C. rubens Maskell and C. kunmingensis Tang et Xie) from 20 different locations in China. For COI data, low GÆC content was found in all species, averaging about 20.4%. Sequence divergences (K2P) between congeneric species averaged 12.19%, while intra-specific divergences averaged 0.42%. All 112 samples fell into six reciprocally monophyletic clades in the COI neighbour-joining (NJ) tree. The NJ tree inferred from 28S showed almost same results, but samples of two closely related species, C. ceriferus and C. pseudoceriferus, were clustered together. This research indicates that the standard barcode region of COI can effi- ciently identify similar Ceroplastes species. This study provides an example of the usefulness of barcoding for Ceroplastes identification.
Keywords: 28S, Ceroplastes, COI, DNA barcoding, DNA markers, wax scales Received 11 January 2012; revision received 21 March 2012; accepted 30 March 2012
Green, C. rubens Maskell and C. xishuangensis Tang et Xie) Introduction known in China (Tang 1991; Martin & Lau 2011). Among Identification of pest coccoids remains a big problem to them, C. floridensis, C. japonicus, C. ceriferus, C. pseudoce- many applied entomologists because most scale insects riferus and C. rubens are well-known polyphagous pests are small, and closely related species may be very similar infested on crops and ornamental plants around the superficially (Gullan & Kosztarab 1997). Moreover, scale world (Gimpel et al. 1974; Huang & Huang 1988; Smith insects are identified to species level by examining mor- 1986; Ben-Dov 1993; Li 1994; Xie 1998; Wang 2001). Both phological traits present in adult females, which requires immature and adult stages of C. japonicus may be diffi- the preservation of the adult cuticle, proper preparation of cult to distinguish from C. floridensis (Longo 1985; Pellizz- specimens and examination by a trained taxonomist. Even ari & Camporese 1994). Ceroplastes kunmingensis is also for adult females, variation in characters, such as the stig- very similar to C. floridensis and C. centroroseus as well as matic and dorsal setae (Gimpel et al. 1974; Gullan & C. japonicus, the main difference being unequal claw digi- Kosztarab 1997), often make species identification difficult. tules (Tang 1991). A great deal of confusion exists over Ceroplastes Gray (Hemiptera: Coccidae) contains about the correct use of the names C. ceriferus and C. pseudoce- 138 species in the world (Ben-Dov 1993; Ben-Dov & riferus. Although Kawai & Tamaki (1967) and Tamaki Hodgson 1997). There are 10 Ceroplastes species (C. actini- et al. (1969) treated C. pseudoceriferus as a different species formis Green, C. centroroseus Chen, C. ceriferus (Fabricius), from C. ceriferus, Kawai (1980) considered that C. pseud- C. floridensis Comstock, C. japonicus Green, C. kunmingen- oceriferus and C. ceriferus were synonyms. For these con- sis Tang et Xie, C. murrayi Froggat, C. pseudoceriferus troversies, Gimpel et al. (1974) even considered the possibility that the C. pseudoceriferus specimen studied by Correspondence: Yan-Zhou Zhang, Fax: 86-10-64807099; E-mail: [email protected] Kawai & Tamaki (1967) was C. ceriferus. Although the San-An Wu, Fax: 86-10-62336596; number of spiracular setae and marginal bristle-shaped E-mail: [email protected] setae were important traits, these traits were not always