Neuroterus

Neuroterus
Neuroterus albipes
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Cynipidae
Genus:	Neuroterus Hartig, 1840
Species
many; see text

The galls of Neuroterus numismalis parthenogenetic generation on Quercus robur leaf

Overview of the Jumping Gall

Neuroterus is a genus of gall wasps. Some species produce galls that fall off the host plant and jump along the ground due to the movement of the larvae within.

Neuroterus saltatorius -- formerly named Cynips saltatorius -- produces such Mexican jumping bean-like jumping galls about 1 to 1.5 mm in diameter.

Natural History

The jumping gall, Neuroterus saltatorius, is a Cynipidae wasp species that forms “~1mm” galls on different species of oak trees (Manier, S., Deamer, D. 2014). In California, N. saltatorius produces galls during its asexual generation on the leaves of the valley oak, blue oak, and Oregon oak in June (Smith, J. L. 1995). The galls fall from the leaves of the oak between July and August or September (Smith, J. L. 1995). After falling to the ground, the galls jump in different directions until settling in in the leaf litter where they remain until emergence in spring (Smith, J. L. 1995). Jumping galls on the leaves of the oak are highly parasitized, especially by Amphidocius schickae (Manier, S., Deamer, D. 2014). The galls also represent a unique food source and space for a wide variety of parasites to interact with the wasp larvae (Manier, S., Deamer, D. (2014).

Research

Research from the University of California, Davis and Santa Cruz, found the jumping gall’s jumping activity is affected by temperature and humidity (Manier, S., Deamer, D. 2014). The researchers collected jumping galls that had fallen from trees in the field. They stored the collected galls in a 4 degree Celsius fridge until use. For the experiment, the researchers used small petri dishes and put 10 galls in each dish(Manier, S., Deamer, D. 2014). Then they floated each petri dish over a water bath on a heating plate. The heating plate allowed the researchers to change the temperature of the water bath. They measured the jumping rate of the galls at various temperature ranges(Manier, S., Deamer, D. 2014). From the results, they found between ~20 degrees Celsius and 40 degrees Celsius, the galls actively jumped(Manier, S., Deamer, D. 2014). The same researchers also found relative humidity affected the jumping behavior of the gall. As the relative humidity decreased, the researchers found a increase in the jumping rate of five-fold(Manier, S., Deamer, D. 2014). The researchers also discussed how the jumping activity of the gall may be to protect the gall from desiccation or death(Manier, S., Deamer, D. 2014). This research can help scientists further understand how and which abiotic factors may affect the jumping gall’s behavior.

Species include:

• Neuroterus albipes
• Neuroterus anthracinus
• Neuroterus aprilinus
• Neuroterus cerrifloralis
• Neuroterus lanuginosus
• Neuroterus numismalis
• Neuroterus quercusbaccarum
• Neuroterus saltatorius
• Neuroterus serratae
• Neuroterus tricolor
• Neuroterus umbilicatus

References and External links

Manier, S., Deamer, D. (2014). Jumping Galls: a Novel Mechanism for Motility. Journal of Insect Behavior, 27(6), 716-721.

Smith, J. L. 1995. Life history, survivorship, and parasitoid complex of the jumping gall wasp, Neuroterus saltatorius (Edwards) on Garry oak, Quercus garryana Douglas. Thesis. University of Victoria, Victoria, British Columbia, Canada

• "Neuroterus". Integrated Taxonomic Information System.
• Gall Photo Gallery