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The daily and total prey consumption and the fecundity of the predatorRhyzobius lophanthaeBlaisdell (Coleoptera: Coccinellidae) fed on the scaleAspidiotus neriiBouché (Homoptera: Diaspididae) were studied under controlled laboratory conditions. The prey consumption ofR. lophanthaewas studied on larvae and on virgin adults, and the fecundity on mated females. For the development of the 1 st instar larvae ofR. lophanthaeat 25° C, 1.2 adult femaleA. neriiwere consumed; for the development of the 2nd, 3rd and 4th instar larvae, prey consumption was 2.7, 7.5 and 24.6 adult females, respectively. The duration of the larval development of the 1st, 2nd, 3rd and 4th instars was 3, 2.2, 2.7 and 6.2 days, respectively,R. lophanthaemale and female adults consumed in their lifetime 390.6 and 672.3 adult femaleA. nerii, respectively. Thus, the male’s daily prey consumption came to 7 and the female’s to 12 adult femaleA. nerii. The average fecundity ofR. lophanthaewas calculated to be 633.7 eggs per female and the daily fecundity to be 18–25 eggs. The average longevity was 63.4 days for mated adult females and 119.4 days for unmated.

Coccinella septempunctata(Coleoptera: Coccinellidae) in Greece is a multivoltine species. In the lowlands, all instars are abundant in spring becoming scarce from July until the end of the warm period of the year; they are absent in winter. In June, mostC. septempunctataadults migrate to mountainous aestivo-hibernation sites. Measurements of the duration of pre-oviposition period in females taken monthly from the summit of Mount Kitheron in central Greece (1993–1994) and transferred to laboratory conditions of high temperature (25°C), long day (16 hrs light/24 hrs), and presence of aphids, indicated that theC. septempunctatafemales were in diapause during July and August. The diapause gradually terminated from late August to late October and was followed by a period of quiescence extending from November to March of the following year.

Coccinella septempunctata(Coleoptera: Coccinellidae), field collected from central Greece and reared in cages during 1990–1991 and in vials during 1994–1995 outdoors at Kifissia, Athens, developed 4 complete and a 5thpartial generations per year. In both cases, only adults of the 1st generation reproduced within the year they emerged; 2nd, 3rdand 4thgeneration adults reproduced partly in the year they emerged and partly in the following year; 5thgeneration adults did not reproduce at all in 1990, and eggs/larvae produced by 4thgeneration females in 1994 died before developing into adults. Adults of the 1 st and 5th generations died before winter; those of the 2nd, 3rdand 4thgenerations overwintered successfully. The greatest numbers of eggs were laid by females of the 1stand 2ndgenerations.

Hippodamia (Semiadalia) undecimnotata(Coleoptera: Coccinellidae), collected from central Greece and reared in cages during 1993–1994 and in vials during 1994–1995 outdoors at Kifissia, Athens, completed 5 generations per year. In both cases, adults of the 1st, 2ndand 3rdgenerations reproduced, completing their egg laying in the same year; 4thand 5thgeneration adults reproduced both in the year they emerged and the following year. In both cases, adults of the 1stand 2ndgenerations died before winter; in 1993, adults of the 3rdgeneration died before winter, in 1994, they survived until April 1995. Adults of the 4thand 5thgenerations overwintered successfully. The greatest numbers of eggs were laid by females of the 1stand 2ndgenerations.

In September 1993, a colony ofHarmonia axyridisPallas (Coleoptera:Coccinellidae) was imported from France into Greece. In 1994, insectary-reared adults were released in 11 citrus orchards in four citrus-growing areas of Greece. Between May 19 and June 8, 1994,H. axyridiswas recovered from a total of seven localities in three of these areas. This species was established on orange, mandarin and sour orange trees heavily infested withToxoptera aurantii, Aphis spiraecolaandA. gossypii; its absence from the remaining four localities may have been the result of low prey densities. Twenty-three days after the initial releases,H. axyridislarvae comprised 57.9% and 83.3%, respectively, of the aphidophagous coccinellid larval populations in two localities (on Chios Island). In samples taken at Leonidion 43 days after the introduction release, both adult and larval populations ofH. axyridisrepresented approximately one-third of aphidophagous coccinellid adults and larvae found, whereas the indigenousAdalia bipunctatacomprised about one-half of the population. In cages placed outside the Athens laboratory,H. axyridiscompleted four overlapping generations annually; average longevities of 56.2, 66.8, 78.9 and 102.2 days, respectively, were recorded for the successive generations. Adults of the 3rd and 4th generations overwintered, giving rise to the following year’s 1st generation. Oviposition began in April and emergence of 1st generation adults occurred in mid-May. The egg-laying activity of the females throughout the warm period of the year indicates thatH. axyridisdoes not diapause in summer. From December until March, small aggregations (2-4 individuals) were observed within the cages at protected sites.

Melanaspis inopinataLeonardi (Homoptera: Diaspididae) is a pest of the woody portion of the pistachio tree. Observations on the phenology of this scale species, which is viviparous, were carried out at Avion, Attica, in central Greece, during the years 1990-92.M. inopinatadeveloped one annual generation on pistachio in that region. Females overwintered as not-yet-reproducing adults. Reproductive activity began in late April or the first half of May. The first adults of males appeared in late June or early July. Melanization of the body of immature females was first noticed in early Septenber; all females were melanized by early November. Ovulation was first noticed in mid or late March. An average of 79 ± 16 eggs/female was found in dissections of females at a late stage of ovulation prior to the onset of viviparous activity.