Note on Glycaspis brimblecombei Moore (Hemiptera Psyllidae): A new pest of Eucalyptus in Greece ()
The red gum lerp psyllid, Glycaspis brimblecombei, is one of the 137 species of the genus Glycaspis Taylor, which is associated with Eucalyptus spp. [1]. Having origin from Australia [2], it uses several eucalyptus species as hosts, with a preference on E. camaldulensis and E. tereticornis [3-6]. In the late 1990’s and during 2000’s, it was introduced into a number of countries in the Americas: USA in 1998 [6], Mexico in 2000 [6], Chile in 2002 [7], Brazil in 2003 [8], Argentina [9], Ecuador [10], Venezuela [11], Peru [12]. Later on it was detected in Europe: The Iberian Peninsula [13-15] and Italy [16].
The exact time of arrival of G. brimblecombei in Greece is not known. This species, as mentioned above, is present in Italy [16] and probably was accidentally brought in from the above mentioned country. It was added to the EPPO Alert List in 2002, but deleted in 2006 (the alert had been given for 3 years and no further action was taken) [16].
Eucalyptus leaves infested by G. brimblecombei, with crystal-white coverings on them (Plate 1 ), were collected from Attiki, Central Greece (Pefki, 01.06.13; Amarous- sion, 21.06.13; Plaka, 29.06.13) and Chania, Crete (Chryssopigi, 01.07.13). The infested trees, which belong to E. camaldulensis and E. globulus species, were covered with honeydew excretions and were visited by numerous honeybees in order to collect them.
Glycaspis brimblecombei is the only psyllid known to feed on Eucalyptus in Greece. Infestations of G. brimblecombei are most easily recognized by the conical white coverings (lerps) secreted by the nymphs (Plate 2(a)). The psyllid nymphs are reddish bronze with darker wing pads that have bright white spots (Plate 2(b) ).
Adults are yellow to green in color and are winged and highly mobile (Plate 3 ). The anterior part of the head of the adults has a pair of curious long projections called genae.
Females lay eggs randomly on the leaves or in clusters of 50 - 75 eggs, usually at an angle or perpendicular to the plant surface. Eggs are about 1 mm in length, yellow or cream coloured (Plate 4 ). Detailed descriptions of G. brimblecombei have been published by Moore [2], Halbert et al. [17] and Olivares et al. [7].
Plate 1 . Eucalyptus leaves infested by G. brimblecombei.
(a) (b)
Plate 2. (a) Crystal-white lerp covering a 4th instar nymph of G. brimblecombei; (b) G. brimblecombei nymphs.
Plate 3. Adult of G. brimblecombei.
Brennan and Gill [18] refer the host range of G. brimblecombei in Eucalyptus species: E. blakelyi Maiden, E. brassiana Blake, E. bridgesiana Baker, E. camaldulensis Dehnh., E. camphora Baker, E. dealbata Cunn. Ex Schauer, E. mannifera ssp. maculosa Baker, E. nitens Deane & Maiden, and E. teriticornis Smith, E. diversicolor F. Muell, E. globulus Labill and E. sideroxylon Cunn.
Glycaspis brimblecombei is referred in North America as more damaging than other eucalyptus psyllids, because it can cause defoliation of infested trees, and it has a relatively broad host range among Eucalyptus species [18].
The work on life history and relationships of the red gum lerp psyllid and the survey of its distribution in Greece are continuing, together with research on natural enemies, predators and parasitoids, which will contribute to the control of that pest.