Icerya aegyptiaca (Douglas)

Unruh, Corinne M. & Gullan, Penny J., 2008, Identification guide to species in the scale insect tribe Iceryini (Coccoidea: Monophlebidae), Zootaxa 1803 (1), pp. 1-106 : 74-75

Icerya aegyptiaca (Douglas)

Crossotosoma aegyptiacum Douglas, 1890: 79 .

Icerya aegyptiacum (Douglas) ; Riley & Howard (1890b: 97) [not Riley and Howard (1890a: 256), as in Ben-Dov (2005: 188)].

Icerya aegyptiaca (Douglas) ; Maskell (1893: 247).

Icerya tangalla Green, 1896: 7 . Synonymy by Rao (1951a: 54).

Unmounted material. Dorsum of adult female covered in wax, margin with long waxy extensions, longer at anterior end; posterior tassels covering ovisac, giving it a fluted appearance (adapted from Rao, 1951a).

Slide-mounted material. Adult female oval, 4.3–5.3 mm long, 3.1–3.8 mm wide. Antennae 11 segmented. Eyes, mouthparts and legs as for tribe. Thoracic spiracles as for genus; derm near atrial opening with simple multilocular pores (appearing bluish when stained), each with bilocular centre and 6–8 outer loculi. Hair-like and flagellate setae distributed as for genus. Open-centre pores absent. Simple multilocular pores, similar to vulvar pores, each 13–14 µm in diameter, with bilocular or trilocular centre and 6–12 slightly reniform outer loculi and appearing bluish when stained, forming medial, submedial and submarginal bands from dorsal head to anal opening (absent or reduced to 1 or 2 pores only on dorsal surface of some specimens); scattered across ventromedial head, prothorax and mesothorax, forming a band across metathorax and forming submarginal band around venter; dorsal submarginal band and ventral submarginal band connected to one another via transverse rows of pores across margin. Simple multilocular pores, similar to pores in ovisac band, each with bilocular or trilocular centre and 6–8 outer loculi, forming marginal clusters and covering derm on dorsal surface around other dorsal pores. Ovisac band made of simple multilocular pores, forming band 3 or 4 pores wide, each pore 8–10 µm in diameter, with bilocular to trilocular (sometimes quadrilocular) centre and 6–8 outer loculi.Simple multilocular pores, similar to vulvar pores, each 10–11 µm in diameter, with trilocular centre (appearing elongate) and 5 or 6 outer loculi, scattered on ventromedial abdomen; similar pores, but each pore with bilocular or trilocular centre and 8–12 outer loculi, scattered on ventromedial head and thorax. Vulvar opening as for genus, surrounded by multilocular pores with 16–24 outer loculi; pores forming medial to submedial band across 2 abdominal segments anterior to vulvar opening. Cicatrix round. Abdominal spiracles in 3 pairs. Anal tube as for genus; anal opening as for genus, surrounded by long, hair-like setae and typical pores with bilocular centre and 8–12 outer loculi.

Type data. Crossotosoma aegyptiaca : EGYPT: Intercepted at England. Icerya tangalla : SRI LANKA: Tangalla, ex leaves of unidentified plant.

Type material. Lectotype of Crossotosoma aegyptiacum here designated: ad ♀, “No. 40/BM 1945, 121/ R. Newstead. ”//“ Icerya /(= Crossotosoma )/AEgyptiaca Doug/ ♀ s ( Egypt)./ Alexandra [sic]/1890.” ( BMNH) . Paralectotype: half an antenna and a single leg (same slide as lectotype).

Lectotype of I. tangalla designated by Williams & Watson (1990: 221): ad ♀ ( BMNH).

Other material examined. HONG KONG: ad ♀ , HK, Wanchai Gap Road , ex Alchornea trewioides , 8.xii.2003 (J. H. Martin) ( BME, CMU043 ) ; ad ♀, NT, Lion’s Education Centre , Sai Kung, ex Alchornea trewioides , 5.xii.2003 (C.S.K. Lau & J.H. Martin) ( BME, CMU040 ) . INDIA: 4 ad ♀♀ (2 slides), Calcutta, ex inflorescence of Sago Palm [= Cycas revolute ] ( BMNH, ex collection of Indian Museum); 4 ad ♀♀, 1 3 rd -instar nymph (one slide), Calcutta, ex Croton [= Codiaeum variegatum ] ( BMNH, ex collection of Indian Museum); ad ♀, 3 rd -instar nymph (one slide), Tinnevelly, ex Asystasia chelonoides (Ramakrishna) (BMNH) . AUSTRA- LIA: 3 ad ♀♀ (3 slides), Northern Territory , Howards Springs, 12°27’S, 131°02’E, 12.v.1992 (P.J. Gullan) ( ANIC) .

Taxonomic notes. Refer to the I. aegyptiaca group for discussion of similar species.

Although Williams & Watson (1990) stated that the type material of Crossotosoma aegyptiacum probably was lost, we believe the slide we are designating as lectotype is part of the type series. Douglas (1890) described the species from material sent to him in England from Alexandria, Egypt. In Newstead’s (1894: 28) review of the pest, he stated that he “had specimens of the females from Egypt …”. We believe that the specimens Newstead had were from Douglas’s original collection.

Green never synonymized I. tangalla with I. aegyptiaca officially, although he referred to it as I. aegyptiaca in papers he published subsequent to his description of I. tangalla . However, he reinstated I. tangalla as a species after re-examining the pores of several non-type specimens ( Green, 1932: 32). (The India specimens listed under “Other material examined” may or may not be the specimens he examined for that paper.) In this paper, he provided a more thorough description and illustration of the pore types and their distribution and explained that the distinctive anal/vulvar-like pores present on the derm of I. aegyptiaca were absent from the derm of I. tangalla (except for derm surrounding the genital and anal regions). Rao (1951a: 54) synonymized the two species.

We have examined material of both true I. aegyptiaca and the “tangalla” form and concur with Rao and Williams & Watson that I. tangalla is a synonym of I. aegyptiaca . Although the lectotype of I. aegyptiaca possesses those distinctive pores on the dorsal surface, which are absent from the dorsal surface of the lecto- type of I. tangalla , we have examined different specimens of I. aegyptiaca from the same collection with and without the distinctive pores on the dorsal surface; some specimens possess only 1 or 2 of these pores. The difference in pore types does not seem to be correlated with host plant, locality or season as individuals of both pore types frequently occur together on the same host plant.