Green, 1900
Diagnosis
In life, female scale cover elongate oval, 1.0-1.5 mm long, grey or black or dark chestnut brown, with a well-defined median ridge and a single, transparent terminal exuviae FITHEL3.jpg and FITHEL4.jpg . The adult female is pupillarial, so there is almost no difference in appearance between the adult and the second instar scale covers. Male scale cover white, slightly tricarinate, with transparent terminal exuviae (Davidson and Miller, 1990; Gill, 1997) FITEL.jpg
FITHEL4.jpg .
Body of slide-mounted adult female pupillarial, membranous, with a membranous process present between antennal bases; antennal bases situated submarginally, not expanded into long, sclerotized anterior projections FITES.jpg . Pygidium with zygotic median lobes, forming an apical notch, and all dorsal pygidial ducts small FITHEP.jpg . Second instar pygidium FITE2I.jpg .
Host range
Fiorinia theae has been recorded from hosts belonging to 24 genera in nine plant families (Davidson and Miller, 1990). Camellias are the preferred hosts; F. theae can be reared on butternut squash (Cucurbita moschata) (Chiu and Kouskolekas, 1978). Hosts include species of: Buxus, Camellia, Citrus, Coptosapelta, Euphorbia, Eurya, Gordonia, Ilex, Jasminum, Olea and Ostodes.
Affected plant stages: vegetative growing, flowering and fruiting stages
Affected plant parts: on leaf undersides FITHL1.jpg , occasionally on stems
Biology and ecology
Reproduction is sexual. In India, males are very common; development from egg to adult takes 22-24 days (Das and Das, 1962). In USA (Alabama) in the summer, development from egg to egg-laying female took 60-70 days (English and Turnipseed, 1940). There are several generations per year in the southern US, where the life cycle is completed in 40-65 days (Johnson and Lyon, 1991). In the USA, males are uncommon; each female lays 10-16 eggs that hatch in 7-21 days (Westcott, 1973). In USA (Georgia), Chiu and Kouskolekas, 1980, found that the ratio of males to females in laboratory-reared colonies of F. theae was 2:1. Adult males mated with several females within a short period. After a preoviposition period of 8-9 days, females laid nearly 3 eggs/day during the first 4 days of oviposition. Females of unknown age produced slightly less than 1 egg/day over a period of 1 month. The fecundity of the scale was higher than that reported in the literature.
Fiorinia theae appears to dislike high temperatures and direct sunlight; it prefers the lower surfaces of mature leaves on tea plants, and is usually commonest in the lower (shady) part of the canopy, and in India it is most prolific in the cool season (Das and Das, 1962).
Crawlers are the primary dispersal stage and move to new areas of the plant or are dispersed by wind or animal contact. Mortality due to abiotic factors is high in this stage. Dispersal of sessile adults and eggs occurs through human transport of infested plant material. In Florida, the main cause of mortality was dispersion loss of crawlers; the second most important factor was the action of natural enemies on nymphs (Nagarkatti and Sankaran, 1990).
Symptoms
Fiorinia theae causes yellow blotches on leaves FITHL3.jpg and premature leaf drop (Westcott, 1973); also dieback and stunting in young tea bushes, but mature bushes are less likely to suffer damage (Das and Das, 1962). The scale makes tea bushes weak and unproductive, and persistent attacks may kill pruned bushes (Chua and Wood, 1990).
Economic impact
Gill, 1997, describes F. theae as a serious pest of camellias and other ornamental plants, and Dekle (1970) considered it to be one of the 10 most important pests in nurseries in Florida. Westcott, 1973, described F. theae as a serious pest of ornamental plants, especially in nurseries, and on camellias in the southern USA. Fiorinia theae is a known pest of tea in India, infesting the stem, branches and leaves, making the bushes weak and unproductive; persistent attacks may kill pruned bushes (Chua and Wood, 1990). The species is commonly encountered at plant quarantine inspection.
Detection and inspection methods
Closely examine leaf undersides of Camellia and the other hosts listed above, for elongate oval, grey or black or dark chestnut brown scale covers, each with a well-defined median ridge and a single, transparent terminal exuviae.
Natural enemies
Parasitoids:
- Aphytis fioriniae, in India
- Aphytis theae, in India (Assam); introduced: USA (Florida)
- Aspidiotiphagus sp., in India (Assam)
- Encarsia sp., in India (Assam)
- Encarsia sankarani, in India
Predators:
- Cecidomyiidae (possibly Triommata sp.)., in India (Assam)
- Jauravia quadrinotata, in India (Assam)
- Scymnus sp., in India (Assam)
Pathogens:
- Fusarium coccidicola, in India (Assam)
Distribution
See Fiorinia theae distribution.
Microscopic examination of slide-mounted adult females is required for authoritative identification to species.
Fiorinia coronata Williams and Watson could be misidentified as F. theae, but differs in possessing a rounded, spiculose interantennal process; in F. theae, the interantennal process is elongate, spatulate and smooth FITES.jpg. Fiorinia coronata is known from West Malaysia, Singapore, Indonesia (Irian Jaya), Micronesia, Papua New Guinea and the Solomon Islands, mainly on Palmae and Pandanaceae. There are records on species of Azadirachta, Cocos nucifera, Ficus, Nypa and Pandanus (Williams and Watson, 1988; the Natural History Museum collection, London, UK).
Fiorinia proboscidaria Green FIPROBL1.jpg could easily be misidentified as F. theae, but differs in the head tapering gradually towards the interantennal process, and in having a pair of lateral prominences; anterior spiracle associated with 0-1 spiracular pore only; and about 5 marginal ducts present on each side of the pygidium. In contrast, the head in F. theae is quite rounded and lacks lateral prominences FITES.jpg; each anterior spiracle is associated with about 5 spiracular pores; and there are about 8-10 marginal ducts on each side of the pygidium (Williams and Watson, 1988; Takagi, 1970) FITHEP.jpg. Fiorinia proboscidaria is probably widespread throughout southern Asia, and has been recorded from Tanzania (Zanzibar), India, Sri Lanka, China (Fujian, Gangdong, Guangxi, Jiangxi, Sichuan, Yunnan, Zhejiang), Taiwan, Japan, Ryukyu Islands, Solomon Islands, Fiji, Tahiti, Tonga, Jamaica, Nevis and USA (Hawaii: Oahu) on hosts belonging to the plant families Anacardiaceae, Araceae, Myrtaceae, Palmae, Piperaceae, Rutaceae, Sapindaceae and Umbelliferae, including species of Areca catechu, Citrus, Daucus carota, Epipremnum, Eugenia, Fortunella, Mangifera indica, Piper, Podocarpus, Rhaphidophora, Rosa and Taxus (Borchsenius, 1966; Takagi, 1970; Kawai, 1980; Williams and Watson, 1988; Tao, 1999; Heu, 2002).
Comments
Fiorinia theae is a tropical species that probably originated in eastern Asia. This species has been eradicated from California (Gill, 1997). It has not been recorded from Europe, Africa, Australia, or from the Pacific islands.
Asia
Brunei Darussalam: The Natural History Museum collection, London, UK
China: present, cannot read the details (in Chinese) (Chou, 1982)
Hong Kong: present, no further details (Nakahara, 1982)
India: present, no further details (Takagi, 1970; Nakahara, 1982)
Assam: present, no further details (Danzig and Pellizzari, 1998)
West Bengal: The Natural History Museum collection, London, UK
Indonesia: present, no further details (Nakahara, 1982)
Japan: present, no further details (Takagi, 1970; Kawai, 1980)
Malaysia: The Natural History Museum collection, London, UK
Nepal: The Natural History Museum collection, London, UK
Philippines: present, no further details (Takagi, 1970)
Sri Lanka: present, no further details (Takagi, 1970; Nakahara, 1982)
Taiwan: present, no further details (Takagi, 1970; Wong et al., 1999)
Western Hemisphere
Argentina
Tucumán: present, no further details (Claps et al., 2001a)
Bahamas: present, no further details (Davidson and Miller, 1990)
Honduras: present, no further details (Davidson and Miller, 1990)
Mexico: present, no further details (Davidson and Miller, 1990; Miller, 1996)
USA
Alabama: present, no further details (Nakahara, 1982)
Arkansas: present, no further details (Nakahara, 1982)
District of Colombia: present, no further details (Nakahara, 1982)
Florida: present, no further details (Nakahara, 1982)
Georgia: present, no further details (Nakahara, 1982)
Indiana: present, no further details (Nakahara, 1982)
Louisiana: present, no further details (Nakahara, 1982)
Massachusetts: present, no further details (Nakahara, 1982)
Maryland: present, no further details (Nakahara, 1982)
Missouri: present, no further details (Nakahara, 1982)
Mississippi: present, no further details (Nakahara, 1982)
New York: present, no further details (Nakahara, 1982)
North Carolina: present, no further details (Nakahara, 1982)
Oklahoma: present, no further details (Nakahara, 1982)
Pennsylvania: present, no further details (Nakahara, 1982)
South Carolina: present, no further details (Nakahara, 1982)
Tennessee: The Natural History Museum collection, London, UK
Texas: present, no further details (Nakahara, 1982)
Virginia: present, no further details (Nakahara, 1982)