Premium
The urticating setae of O chrogaster lunifer , an A ustralian processionary caterpillar of veterinary importance
Author(s) -
PERKINS L. E.,
ZALUCKI M. P.,
PERKINS N. R.,
CAWDELLSMITH A. J.,
TODHUNTER K. H.,
BRYDEN W. L.,
CRIBB B. W.
Publication year - 2016
Publication title -
medical and veterinary entomology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.028
H-Index - 82
eISSN - 1365-2915
pISSN - 0269-283X
DOI - 10.1111/mve.12156
Subject(s) - seta , instar , biology , pupa , larva , moulting , anatomy , zoology , veterinary medicine , ecology , medicine , genus
The bag‐shelter moth, O chrogaster lunifer H errich‐ S chaffer ( L epidoptera: N otodontidae), is associated with a condition called equine amnionitis and fetal loss ( EAFL ) on horse farms in A ustralia. Setal fragments from O. lunifer larvae have been identified in the placentas of experimentally aborted fetuses and their dams, and in clinical abortions. The gregarious larvae build silken nests in which large numbers cohabit over spring, summer and autumn. The final instars disperse to pupation sites in the ground where they overwinter. Field‐collected O. lunifer larvae, their nests and nearby soil were examined using light and electron microscopy to identify setae likely to cause EAFL and to determine where and how many were present. Microtrichia, barbed hairs and true setae were found on the exoskeletons of the larvae. True setae matching the majority of setal fragments described from equine tissue were found on third to eighth instar larvae or exuviae. The number of true setae increased with the age of the larva; eighth instars carried around 2.0–2.5 million true setae. The exuvia of the pre‐pupal instar was incorporated into the pupal chamber. The major sources of setae are likely to be nests, dispersing pre‐pupal larvae and their exuviae, and pupal chambers.