Threats

Blue gum psyllid/ Ctenarytaina eucalypti

Blue gum psyllid/ Ctenarytaina eucalypti
Ctenarytaina eucalypti Maskell
Sap sucking

Ctenarytaina eucalypti primarily infests and feeds on young Eucalyptus plants and fresh shoot material. Although occasionally observed on new growth of mature trees in the field, it is more commonly found infesting seedlings in nurseries or seedlings and saplings in recently established compartments. Feeding activity can cause leaf discoloration and die-back. During severe infestations, premature leaf drop, leaf curling, malformation, and stunting may occur due to damage to primordial leaves. Besides direct feeding damage, plants may also experience indirect effects from sooty mold growth, which develops as a result of honeydew production by the psyllids. Heavy sooty mold accumulation can reduce the photosynthetic capacity of young plants, exacerbating leaf discoloration, premature leaf drop, and stunting. Typically, damage caused by the psyllid is superficial, and trees can recover depending on their vigor and stress levels.
(Based on Hodkinson 1999; das Graças do Carmo et al. 2025)

Eggs are oval-shaped, typically yellow but vary in color according to developmental stage, and are laid in groups.
Nymphs undergo five instar stages during development. The first instar is yellow with red eyes; as nymphs mature, they increase in size and develop wing pads, which turn brown by the fifth instar.
Adults are highly mobile winged insects characterized by oval forewings with rounded apices and eight-segmented antennae. Body coloration ranges from yellow to brown. Sexual dimorphism is evident, with males and females differing in size and coloration.
(Based on Hodkinson 2007)

Eucalyptus psyllids exhibit multiple generations annually. Ctenarytaina eucalypti typically produces two to three overlapping generations per year, with up to four generations recorded depending on climatic conditions and host availability. The average life cycle spans approximately 149 days from egg to mature adult. A single female can lay up to 160 eggs during a 16-day oviposition period, depositing them in clusters of about ten on leaf axils and lamina. Nymphs progress through five instars before reaching adulthood. Generations often overlap, with all stages feeding simultaneously on young leaves and shoot material.

(Based on Pinzón et al. 2002 and Makunde thesis 2022)

1925 (Pettey 1925)
Various species of Eucalyptus and Corymbia and their hybrids including: Corymbia citriodora, Eucalyptus archen, E. benthamii, E. bicostata, E. camaldulensis, E. cinerea, E. citriodora, E. cordata, E. crenulata, E. dalrympleana, E. dunni, E. glaucescens, E. globulus, E. gunnii, E. leucoxylon, E. macarthuri, E. maidenii, E. mannifera, E. neglecta, E. nicholi, E. nitens, E. nitida, E. perrimana, E. pulverulentus, E. rubida, E. urnigera , and E. viminali (based on Hodkinson 1999; Makunde thesis 2022; and das Graças do Carmo et al. 2025)
Australia

Gallery

Hodkinson, I. D. (1999) Biocontrol of eucalyptus psyllid Ctenarytaina eucalypti by the Australian parasitoid Psyllaephagus pilosus: a review of current programmes and their success. Biocontrol News and Information, 20.4: 129N-134N.

das Graças do Carmo, D., et al. (2025) Global risks of Ctenarytaina eucalypti to eucalyptus plantations under climate change: broad or limited?. Theoretical and Applied Climatology, 156(6): 321.

Hodkinson, I. D. (2007) A new introduced species of Ctenarytaina (Hemiptera, Psylloidea) damaging cultivated Eucalyptus parvula (= parvifolia) in Europe. Deutsche Entomologische Zeitschrift, 54(1): 27-33.

Pinzón F, O. P., M. Guzmán C, and F. Navas N. (2002) Contribution to the knowledge of biology, natural enemies and damage of Ctenarytaina eucalypti (Homoptera: Psyllidae). Revista Colombiana de Entomología, 28(2): 123-128.

Makunde, P. T. (2022) Biology and ecology of Eucalyptus psyllid pests in South Africa. Diss. University of Pretoria.

Pettey, F.W. (1925) New South African psyllids. South African Journal of Natural History 5: 125-142