Feeding and survival of two nocturnal cursorial spiders on extrafloral nectar and honeydew sugars

Authors: Pfannenstiel, Robert; Patt, Joseph - Joe

Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/11/2010
Publication Date: 12/1/2012
Citation: Pfannenstiel, R.S., Patt, J.M. 2012. Feeding and survival of two nocturnal cursorial spiders on extrafloral nectar and honeydew sugars. Biological Control. 63:231-236. 2012.

Interpretive Summary: Nectars and insect produced honeydews may be important resources for nocturnal cursorial spiders. C. inclusum spiderlings given only water survived an average of only 6.1 d. Feeding on cotton extrafloral nectar and mealybug honeydew extended their lives to 52.6 and 37.9 d, respectively (870% and 626% increases). Choice tests showed that feeding on sugar solutions was not because of a need for water. Sugars that make up extrafloral nectar (sucrose, glucose and fructose) and honeydews (maltose, melezitose and raffinose) were all acceptable for feeding by H. futilis. Consumption of each of the sugars improved spiderling survival over that of water. The improvement in mean H. futilis survival over water varied from 394% for raffinose (mean = 16.6 d) to 1414% for maltose (mean = 56.9 d). The remaining four sugars extended survival more than 1079%. With survival of H. futilis between 1079 and 1414% longer when feeding on most sugars than on water alone, that spiderlings survived for weeks on diets comprised only of individual sugars indicates that the availability of nectar and honeydew can be important for spider survival.

Technical Abstract: Sugars in the form of extrafloral nectar and honeydews may be important resources for nocturnal cursorial spiders such as Cheiracanthium inclusum (Hentz) and Hibana futilis (Banks). C. inclusum spiderlings given only water survived an average of only 6.1 d. Feeding on cotton extrafloral nectar and mealybug honeydew extended their survivorship to an average of 52.6 and 37.9 d, respectively (870% and 626% increases). Choice tests demonstrated conclusively that feeding on sugar solutions was not due to a need for moisture. Component sugars of extrafloral nectar (sucrose, glucose and fructose) and honeydews (maltose, melezitose and raffinose) were equally acceptable for feeding by H. futilis. Consumption of each of the individual sugars improved spiderling survival significantly over that of water. The percent improvement in mean H. futilis survival over water alone varied from 394% for raffinose (mean = 16.6 d) to 1414% for maltose (mean = 56.9 d). The remaining four sugars extended survival greater than 1079%. With mean survival times for H. futilis between 1079 and 1414% greater when feeding on most sugars than on water alone, that spiderlings survived for weeks on diets comprised only of individual sugars indicates that the availability of nectar and honeydew can be of considerable importance to the survivorship of cursorial spiders in the field.