Valid Names Results
Cystococcus Fuller, 1897 (
Eriococcidae)
Nomenclatural History
- Cystococcus
Fuller
1897b: 1346.
Type species: Cystococcus echiniformis Fuller
by monotypy
.
accepted valid name
Notes: This genus was considered by Cockerell (1902g), Fernald (1903b) and Hoy (1963) to be a junior synonym of Ascelis, but the concept of Gullan & Cockburn (1986) is that they are distinct, but closely-related genera.
Remarks
- Systematics: This genus was considered to be a junior synonym of Ascelis by Cockerell (1902), Fernald (1903) and Hoy (1963), but Gullan and Cockburn (1986) and Gullan et al. (2005) treated the two genera
as distinct. Physical characteristics of adult females of Cystococcus are minimal, including no eyes, antennae, legs or wings, and there is minimal sclerotization other than the button.
The genus contains 3 species, all of which induce galls (known as
‘bloodwood apples’ or ‘bush coconuts’) on the stems of Corymbia species (Myrtaceae). Cystococcus species may be the only insects to provide intersexual phoresy for their crawlers (see Gullan & Cockburn 1986; Semple et al. 2015). Adult males of all 3 known species were described in Semple et al. (2015).
- Structure: Forming some of the largest and most conspicuous of all coccoid galls on Australian Eucalyptus and Melaleuca species by eriococcids (Beardsley, 1984).
An unusual morphological characteristic of Cystococcus is the absence of loculate pores on any instar, and the presence of ‘pore plates’ on the dorsal derm of second-instar males and the ventral derm of adult females. On adult females, pore plates are numerous surrounding the spiracles and on several segments of the abdominal venter. Scanning electron microscopy shows each plate of the adult female to be composed of several rounded tubercles, the so-called ‘pores’, clustered together and surrounded by a rim of sclerotized cuticle to form a plate. There are no loculi and any exudation must be secreted across the cuticle. These pore plates appear to produce white powdery wax on live adult females. The spiracles lack this type of powdery wax but exude long (perhaps up to 400 mm), silvery filaments. (Semple, et al., 2015)
- Biology: "Females of Cystococcus cause large woody subspherical galls to develop on the stems of their bloodwood eucalypt hosts. The male offspring complete their development within the maternal gall where they feed on a layer of white nutritive tissue lining the gall cavity. Male development within the maternal gall is not unusual among gall-forming eriococcids since at least three other taxa display similar habits....The coupling of sexual dichronism and development of male offspring within the maternal gall facilitates an extraordinary form of phoresy, in which the newly emerged female first instar nymphs are transported out of the maternal gall on the modified abdomens of their adult brothers. The males leave the gall through an orifice, 0.5-1.7mm in diameter, which is plugged by the sclerotized apex of the mother's abdomen until the completion of parturtition. The adult male lives less than 48 hours, as in other members of the Coccoidea (Gullan & Cockburn, 1986)."
- General Remarks: Detailed description and analysis in Semple, et al., 2015. Genereic diagnosis of the male Hodgson, 2020.
Keys
- Hodgso2020: pp.19-22
(
Adult (M)
)
[Neococcoid higher taxa]
- Hodgso2020: pp.73
(
Adult (M)
)
[some “Gondwanan” Eriococcidae]
- GullanWi2016: pp.89
(
Adult (F)
)
[Eriococcidae found on Eucalyptus and Corymbia in Australia]
- HardyBeGu2011: pp.502-504
(
Adult (F)
)
[Key to the adult females of genera of felt scales on Eucalyptus and Corymbia]
Associated References
- AustinYeCa2004:
ecology, host, pp. 220
- Cocker1899a:
taxonomy, pp. 393
- Cocker1899m:
taxonomy, pp. 276
- Cocker1902g:
taxonomy, pp. 114
- Fernal1903b:
distribution, pp. 48
- Frogga1921a:
taxonomy, pp. 114, 156
- Fuller1897b:
description, distribution, host, taxonomy, pp. 1346
- Fuller1899:
taxonomy, pp. 462
- GullanCo1986:
taxonomy, pp. 632
- GullanKo1997:
pp. 37, 38, 40
- GullanMiCo2005:
ecology, host, pp. 166
- HardyBeGu2011:
host, taxonomy, pp. 498,502-503
- HardyGu2007:
host, illustration, taxonomy, pp. 106-108
- Hodgso2020:
description of male, diagnosis, key, pp. 20, 73, 83-84
- Hoy1963:
catalog, taxonomy, pp. 46
- KondoGu2022:
economic importance, pp. 4
- Lindin1937:
taxonomy, pp. 183
- MacGil1921:
taxonomy, pp. 204
- MillerGi2000:
catalog, taxonomy, pp. 95-96
- MorrisMo1966:
taxonomy, pp. 53
- SempleGuHo2015:
description, description of male, diagnosis, illustration, key, life history, morphology, taxonomy, pp. 294-296
- Theron1968:
taxonomy, pp. 96
- Willia1991DJ:
pp. 457
- WoodwaEvEa1970:
distribution, host, pp. 430
3 Species
