Scale cover of adult female in life oval, convex, dirty white to mid-brown, with buff to red-brown submarginal exuviae that may be paler or darker than the secreted scale HEMPITL3.jpg . Scale cover of male not documented.
Slide-mounted adult female membranous and pyriform HEMPITS.jpg . Pygidium with large median lobes, separated by at least 1/3 of the width of a median lobe; second lobes reduced but sclerotized; third lobes very reduced or completely obsolete; a large anal opening situated near the posterior margin of the pygidium (less than 2.3 times its length from base of median lobes); paraphyses shorter than the lobes, present only on the margin between the third lobes; perivulvar pores present; and plates reaching beyond tips of median lobes, moderately to little fringed, the outermost plates being the smallest and least elaborate HEMPITP.jpg .
Hemiberlesia pitysophila has been recorded from the needles of trees belonging to the plant family Pinaceae, genus Pinus (Takagi, 1969; Tao, 1999). Hosts include: P. elliotii, P. massoniana and P. thunbergii.
Affected plant stages: vegetative growing, flowering and fruiting stages
Affected plant parts: on the needles HEMPITL2.jpg and HEMPITL1.jpg
Biology and ecology
Pan et al., 1989, found that H. pitysophila had 5 overlapping generations/year in China. Temperature was the main factor influencing the population growth and forest decline, and pest mortality increased when the temperature was above 23°C or lower than 18°C. Dense stands favoured the incidence and development of the pest.
In China, Tong et al., 1988, found that air temperature was the main influence on population size, with 19.5°C averaged over 10 days being the optimum for the growth and development of the insect, but monthly precipitation over 100 mm was detrimental to reproduction. In Ishigaki Island, Japan, survival of H. pitysophila from crawler to ovipositing female was estimated to be 8.41% (Gu and Murakami, 1990).
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.
Heavy infestations of H. pitysophila can kill pine trees.
Hemiberlesia pitysophila is an introduced pest of pine trees in China (Guangdong) (Lian and Tang, 1985). Pan et al., 1987, reported that at high population densities it can kill both young and old pine trees within 3-5 years. It has spread through 16 Chinese counties since 1982, infesting 4 700 000 mu (1 mu = 0.067 ha) of pine forest, of which 1 2000 000 mu has been destroyed. Pinus elliottii, P. caribaea, P. taeda and P. thunbergii are fairly tolerant of the pest, but are inferior to P. massoniana in afforestation programmes. The species is a pest of Pinus luchuensis in Japan (Tachikawa, 1988).
Detection and inspection methods
Examine needles of the hosts listed above, for oval, convex, dirty white to mid-brown scale covers, each with buff to red-brown submarginal exuviae that may be paler or darker than the secreted part of the scale.
Hemiberlesia pitysophila is a damaging pest of pine tree plantations, especially when introduced in the absence of natural enemies. Planting material of Pinus species should not be transported from China or Japan to other countries without thorough phytosanitary precautions.
- Coccobius azumai, attacking adult females, in Japan (Okinawa); introduced: China (Guangdong)
- Encarsia amicula, in China
- Encarsia citrina, in China
- Marietta carnesi, in China
- Anystis baccarum, in China
- Cladosporium cladosporioides, in China
See Hemiberlesia pitysophila distribution.
Microscopic examination of slide-mounted adult females is required for authoritative identification to species.
Hemiberlesia pitysophila is a native of the Far East, but did not occur originally in China. It has not been recorded from Europe, Africa, the Western Hemisphere, Australia, or from the Pacific islands.
Guangdong: present, no further details (Wilson, 1993; Tao, 1999)
Hainan: present, no further details (Tao, 1999)
Hong Kong: present, no further details (Wilson, 1993; Tao, 1999)
Macau: present, no further details (Tao, 1999)
Shanxi: present, no further details (Xie, 1982)
Japan: present, cannot read any further details (Kawai, 1980; Tao, 1999)
Okinawa: present, no further details (Tachikawa, 1988)
Taiwan: present, no further details (Wong et al., 1999)