Threats

Eucalyptus shoot psyllid/ Blastopsylla occidentalis

Eucalyptus shoot psyllid/ Blastopsylla occidentalis
Blastopsylla occidentalis
Sooty mold
Sap sucking

Blastopsylla occidentalis predominantly infests young Eucalyptus trees in nursery settings and newly established plantation compartments, although it can also colonize the young apical shoots of mature trees. The psyllid inflicts damage through its feeding, causing necrosis and damage to leaf tissues that often result in premature leaf drop. Severe infestations may result in partial defoliation of the trees, leading to canopy thinning. Additionally, severe infestations and high feeding damage can cause leaf malformations and death of growth tip, resulting in stunting of the trees. The excretion of honeydew promotes the growth of sooty molds on leaf surfaces, which indirectly reduces photosynthetic capability and overall tree vigor. 

(Based on de Queiroz et al. 2018)

Eggs of Blastopsylla occidentalis are spherical and yellow in coloration. The species undergoes five larval instars prior to reaching the adult stage. All instars are yellow and exhibit prominent setal hairs on the posterior abdominal region. Morphological differentiation among nymphal instars is primarily based on antennal segmentation and development. The first instar displays four-segmented antennae and lacks wing pads. Transitioning to the second instar, an additional antennal segment is formed, and forewing and hindwing pads begin to develop, accompanied by initial abdominal segmentation. In the third instar, the antennae acquire a sixth segment, and a rhinarium appears on the fourth antennal segment; wing pads and abdominal segmentation become more pronounced. The fourth instar features the development of a seventh antennal segment and a second rhinarium on the sixth segment, with significantly enlarged wing pads. During the fifth and final instar, two additional antennal segments develop, with rhinaria present on segments three, five, seven, and eight; segments eight and nine exhibit a darker brown coloration, and the ninth segment bears concave setal hairs.

Newly emerged adults are yellow, with brown pigmentation on the head and thorax, darkening with age. The eyes possess a purplish hue. Antennae consist of ten segments, exhibiting a greyish-brown coloration with the two terminal segments darker. Sexual dimorphism is present; females are typically darker, larger, and longer than males. Forewings are hyaline, rounded at the apex, with brown venation and greyish cells.

(Based on Tamesse et al. 2010)

Blastopsylla occidentalis undergoes a complete metamorphic life cycle comprising several distinct developmental stages. The process begins with the egg stage, followed by 5 nymphal instars. On average, the total duration of development from egg to adult is 32 days. Adult psyllids live for about 11 days on average, during which females typically lay around 38 eggs, mostly on young plant tissues such as buds, leaves, and twigs, with oviposition commencing about 8 days post-emergence.​

The life cycle is characterized by high reproductive output and overlapping generations—up to nine may occur simultaneously on a single host, facilitating rapid population growth. Adults possess wings, enabling dispersal through flight, which can contribute to the spread of infestations across host plants and plantations. 

(Based on Dzokou et al. 2020)

2007 (Neser & Millar, 2007)
All Eucalyptus growing provinces
Various Eucalyptus and Corymbia species and their hybrids including: Corymbia citriodora, Eucalyptus blakelyi, E. brassiana, E. camaldulensis, E. deglupta, E. forrestiana, E. globulus (and its ssp. maidenii), E. grandis, E. gomphocephala, E. lehmannii, E. longirostrata, E. conf. microneura, E. microtheca, E. nicholii, E. oleosa, E. conf.platypus, E. polyanthemos, E. robusta, E. sideroxylon, E. rudis, E. saligna, E. spathulata, E. tereticornis, E. urophylla and, E. viminalis (de Queiroz et al.2018, Makunde et al. 2020)
Australia

Gallery

Tamesse, J.L., et al. (2010) First record of Blastopsylla occidentalis Taylor, 1985 (Hemiptera: Psyllidae), a Eucalyptus psyllid in Cameroon, Central Africa. Entomological Research 40(4): 211-216.

de Queiroz, D.L., et al. (2018) New country, Brazilian states and host records of the eucalypt shoot psyllid Blastopsylla occidentalis. Pesquisa Florestal Brasileira 38

Dzokou V.J., Soufo L., Tamesse J.L. (2020) Biology of Blastopsylla occidentalis (Hemiptera: Psylloidea: Aphalaridae), a pest of Eucalyptus globulus (Myrtaceae) in Yaoundé, Cameroon. Journal of Applied and Natural Science, 12: 30–35

Makunde, P.T., et al. (2020) Current and potential threat of psyllids (Hemiptera: Psylloidea) on eucalypts.Southern Forests: a Journal of Forest Science, 82(3): 233-242.