Valid Names Results
Discochiton expansum (Green, 1896) (Coccidae: Discochiton)Nomenclatural History
- Lecanium expansum Green 1896: 9. Type data: SRI LANKA: Punduloya, on Litsea sp. and Dalbergia sp.. Syntypes, female, Type depository: London: The Natural History Museum, England, UK; accepted valid name
- Lecanium (Paralecanium) expansum; Cockerell & Parrott 1899: 227. subsequent use
- Paralecanium expansum (Green, 1896); Fernald 1903b: 199. change of combination
- Discochiton expansum (Green, 1896); Hodgson & Williams 2018: 28-33. change of combination
Common Names
Ecological Associates
Hosts:
Families: 13 | Genera: 17
- Amphorogynaceae
- Dendrotrophe frutescens | HodgsoWi2018
- Annonaceae
- Annona reticulata | HodgsoWi2018
- Polyalthia longifolia | HodgsoWi2018 | subspecies pendula
- Arecaceae
- Dypsis | Suh2023
- Calophyllaceae
- Calophyllum | Ali1971 Ramakr1930 ShafeeYoKh1989
- Fabaceae
- Dalbergia | Ali1971 Green1896 Green1904d Green1937
- Dalbergia pseudo-sissoo | HodgsoWi2018 | (= Dalbergia championii)
- Lauraceae
- Litsea | Ali1971 Green1896 Green1904d Green1937
- Litsea glutinosa | Green1904a LinKoGu2013 | (= Lepidadenia wightiana)
- Machilus | Ali1971
- Machilus thunbergii | TaoWoCh1983
- Neolitsea zeylandica | HodgsoWi2018
- Moraceae
- Ficus | Green1904d
- Ficus macrophylla | Frogga1915
- Ficus microcarpa | HodgsoWi2018
- Ficus pumila | TaoWoCh1983
- Ficus retusa | Ali1971 Green1908a Ramakr1930 ShafeeYoKh1989
- Myricaceae
- Myrica rubra | Ali1971 TaoWoCh1983 ZarkanApTu2021
- Myristicaceae
- Gymnacranthera | HodgsoWi2018
- Myristica fragrans | HodgsoWi2018
- Putranjivaceae
- Drypetes | HodgsoWi2018 | (= Hemicyclia)
- Santalaceae
- Viscum orientale | HodgsoWi2018
- Sapotaceae
- Mimusops | HodgsoWi2018
- Zingiberaceae
- Zingiberaceae | Green1904a
Geographic Distribution
Countries: 13
- Australia
- Queensland | Frogga1915 HodgsoWi2018
- China
- Xianggang (=Hong Kong) | MartinLa2011
- India | Green1908a Ramakr1930 ShafeeYoKh1989
- Indonesia | HodgsoWi2018
- Java | Ali1971 Green1904a
- Japan |
- Laos |
- Malaysia | Suh2023
- Papua New Guinea | HodgsoWi2018
- Singapore | BenDov1993
- Sri Lanka | Ali1971 Green1896 Green1904d Green1937
- Taiwan | Ali1971
- Thailand | HodgsoWi2018
- Vietnam | HodgsoWi2018
Keys
- HodgsoWi2018: pp.16-18 ( Adult (F) ) [species of Discochiton]
- ChoiSoLe2018: pp.6-7 ( Adult (F) ) [Coccidae in Laos]
- Tang1991: pp.127 ( Adult (F) ) [Asia]
- TaoWoCh1983: pp.100 ( Adult (F) ) [Taiwan] Key as: Paralecanium expansum
- Kawai1980: pp.146 ( Adult (F) ) [Japan]
Remarks
- Systematics: Subfamily: Coccinae: Paralecaniini (Choi & Lee, 2019) Adult female D. expansum appear to be rather variable, particularly in the number of spines in each stigmatic cleft. The type series from Sri Lanka and the specimens from Australia usually have 4 or more spines per cleft, whereas almost all other specimens of D. expansum have only 3 per cleft. As the lectotype specimen has 3 spines in three of the clefts but 6 in the fourth, it appears that this variation does not indicate a specific difference. The main characteristic diagnosing adult female D. expansum is the presence of unsegmented leg stubs. Other significant characteristics are: (i) preopercular pores absent from anteriormost clear areas (CA1 and CA2; rarely with a few present associated with CA2) and clearly most abundant associated with the posterior two clear areas (CA3 and CA4)); (ii) stigmatic spines all rather long and narrow, often rather bent; (iii) dorsal setae parallel sided or capitate, generally with some setae present submedially; (iv) marginal setae fan-shaped and most distinctly wider than long; (v) multilocular disc-pores present on segment V, and (vi) marginal ornamentation in the form of shallow castellations with short radial lines. (Hodgson & Williams, 2018)
- Structure: See colour photograph in Kawai (1980, Fig. 6,17), Wong et al. (1999).Members of the expansum-group are completely without legs. (Martin & Lau, 2011) A very large flattish species. Longest diameter nearly 1/3 inch.’ (Green, 1896, p. 9). A large coccid with margin very pale, then a black border, then greenish with darker markings in the posterior half. Slide-mounted adult female. Body almost round. Length 3.0–6.5 mm, width 2.5–5.5 mm. (Hodgson & Williams, 2018)
- Biology: Bisexual reproduction with a Lecanoid heterochromatinization in male embryos. Complete ovoviviparity. (Gavrilov-Zimin, 2020)
- General Remarks: Good description and illustration of adult female by Tao et al. (1983) and by Tang (1991). Detailed redescription and illustrations in Hodgson & Williams, 2018.
Illustrations
Citations
- Ali1971: distribution, host, 36-37
- BenDov1993: catalog, 203
- ChoiLe2019: phylogeny, taxonomy, wax secretion, 402, 404
- ChoiSoLe2018: diagnosis, distribution, host, illustration, 37-38
- Cocker1896b: distribution, host, 332
- CockerPa1899: taxonomy, 227
- DiSoraTuBr2023: phylogeny, 7, 8
- Fernal1903b: 199
- Frogga1915: description, distribution, host, illustration, taxonomy, 606
- Gavril2020: cytogenetics, distribution, reproduction, 346
- Green1896: distribution, host, 9
- Green1904a: distribution, host, 205
- Green1904d: description, distribution, host, illustration, taxonomy, 235-236
- Green1908a: distribution, host, 29
- Green1937: catalog, distribution, host, 305
- HodgsoWi2018: Grapevine leafroll disease transmission, description, diagnosis, distribution, host, illustration, key, taxonomy, 28-33
- Kawai1980: description, distribution, host, taxonomy, 146
- Kotins1908: distribution, host, 167
- LinKoGu2013: distribution, host, molecular data, phylogeny, taxonomy, 253, 258
- MartinLa2011: catalog, distribution, 36
- Ramakr1921a: catalog, distribution, host, 348
- Ramakr1930: distribution, host, 47
- ShafeeYoKh1989: distribution, host, 52
- Suh2023: distribution, host, 5
- Takaha1928: distribution, host, 343-344
- Takaha1929: distribution, host, taxonomy, 57
- Takaha1934: distribution, host, 36
- Tang1991: description, distribution, host, illustration, taxonomy, 127-128
- Tao1978: distribution, host, taxonomy, 82
- Tao1989: catalog, distribution, 59
- Tao1999: distribution, host, taxonomy, 61-62
- TaoWoCh1983: description, distribution, host, illustration, taxonomy, 100-102
- UsmanPu1955: distribution, host, 50
- Varshn1992: distribution, host, taxonomy, 93
- WilliaDe2020: taxonomy, 198
- WongChCh1999: description, distribution, host, taxonomy, 15-16,54
- Yang1982: description, distribution, host, taxonomy, 164,191
- ZarkanApTu2021: distribution, host, 157
