2021 AMI Online Salon

Tritrophic interaction – Phragmites reed, Roseate Scale and Parasitic wasps

Project Details

  • Entrant Name:  Taina Litwak
  • Other Contributors Rodrigo Diaz, Scott Schneider
  • Client: US Dept. of Agriculture
  • Copyright: US Dept. of Agriculture, 2021
  • Medium/software used: Adobe Photoshop
  • Final presentation format: Journal cover, individual elements for PowerPoint presentations
  • Primary Audience: Entomologists and invasives control professionals

Project Description

This illustration is devoid of type at the authors’ request. The purpose is to illustrate the Phragmites reed (Phragmites australis) and the biology of the invasive Roseau Cane Scale Scale insect (Nipponaclerda biwakoensis) which causes damage to reed beds. The Scale live beneath the leaf sheaths and feed by inserting a long proboscis into the phloem cells of the reed stem.  Life stages of Scale illustrated: just hatched “crawlers”, newly settled immatures, a mobile male and the large sessile females. Another element is the thick root system of the reed holding the delta soil and the erosion that occurs after the reed die off due to scale infestation. Two species of parasitic wasps (Astymachus lasallei and Boucekiella depressa) are illustrated. They oviposit into the female scale and as the wasp larvae grow and pupate the husk of the dying scale turns dark. Wasp pupae inside can be seen. Interestingly, two different species of wasp can use a singe individual scale insect as a host.