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December 2011. In May 2008, Dr. Aunu Rauf, Bogor Agricultural University and Dr R Muniappan visited Bogor Botanic Gardens to verify an earlier report that cycad collections in the garden were decimated by the Asian cycad scale or Cycad aulacaspis scale, Aulacaspis yasumatsui.
The scale was not found on cycads in the garden and all were healthy. However, in a recent trip, on November 7, 2011, A. yasumatsui was present on cycads in the Bogor Botanic Gardens and some trees were severely affected. The identity of this scale was facilitated by Dr. Gillian Watson and confirmed by Dr.Natalia von Ellenrieder, California Department of Food and Agriculture. Ten species of the genus Cycas are known to occur in Indonesia. Unless prompt action is taken, these species may be endangered by this scale insect.
A response was sent from a PestNet modertor:
The cycad scale, Aulacaspis yasumatsui was described by Takagi in 1977 from specimens collected in Bangkok in 1972-73 by Prof K. Yasumatsu. By shipping cycads from Thailand to Miami Botanic Garden in Florida, the scale was found devastating on cycads in 1996, and then found spreading across the USA to California and Hawaii. The most susceptible cycad is an exotic Cycas revoluta Thunb. or Japanese cycad used widely as ornamentals.
Dr R.M. Baranowski of the University of Florida, Homestead and I initiated a biological control project searching for its natural enemies in Thailand. We found no scale on other native cycads in Thailand, namely, C. circinalis L., C. micholitzii Dyer var. simplicipinna Smithin., C. pectinata Griff., C. rumphii Miq. and C. siamnensis Miq.
On C. revoluta we found a predatory nitidulid, Cybocephalus binotatus Grouvelle (Coleoptera: Cybocephalidae) and a parasitoid,Coccobius fulvus (Compere & Annecke) (Hymenoptera: Aphelinidae). Both C. binotatus and C. fulvus were introduced to Florida in 1997 and 1998. According to Dr Baranowski, both of them after field releases have provided satisfactory control.
I have also managed to introduce them to Taiwan in collaboration with
Dr Po-Yung Lail. C. binotatus seems to be a better biological control agent. I also observed C. nipponicus attacking A. yasumatsui on C. revolutain Jiangshir Imperial Park in Beijing in May 2004.
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