Life History Comparisons of Ground‐ and Canopy‐Nesting Populations of Ochrogaster lunifer Herrich‐Schaffer (Lepidoptera: Thaumetopoeidae): Evidence for Two Species?

Abstract

Populations of Ochrogaster lunifer Herrich-Schaffer display different larval behaviours (ground-nesting and canopy-nesting), suggesting the existence of two or more species. Here, the behaviour and biology of ground-nesting populations are described from extensive surveys in southeastern Queensland. Females oviposit at the base of the host tree, covering the eggs with scales from the anal tuft. The larvae are processionary and pass through eight instars. First instars do not feed, remaining at the base of the tree trunk within the scale mass. Second instars ascend the tree in single file in the morning to feed in the canopy each day, returning to the scale mass after several hours. Later instars feed only at night. Six new host plants are recorded: five species of Acacia, and one species of Casuarina. Predators and parasitoids recorded on 0. lunifer included chalcidoids, dermestids, tachinids and a predatory pyrrhocorid bug. The results of the study highlight a number of major differences between ground-nesting and canopy-nesting populations. Differences include habitat and geographical distribution; host plant range; number of instars; size and colour of final instar; size of adult female; oviposition site and larval behaviour. These differences provide further evidence for the existence of two species.

Thigmotaxis maintains processions of late‐instar caterpillars of Ochrogaster lunifer

“…The possibility that thigmotaxis is the mechanism that maintains processions of O. lunifer caterpillars has not been tested experimentally. Although some aspects of the biology and ecology of O. lunifer are reported (van Schagen et al ., 1992a, b; Floater, 1996a, b, c, 1997, 1998; Floater & Zalucki, 1999, 2000), the absence of any detailed information about processionary behaviour represents a notable deficiency in the available literature. This deficiency exists because caterpillars are considered to having urticating setae that are able to cause skin rashes and dermatitis (Southcott, 1978, 1987).…”

The Brooks‐Dyar Rule and Morphometrics of the Processionary Caterpillar Ochrogaster Zunifer Herrich‐Schäffer (Lepidoptera: Thaumetopoeidae)

“…While Common (1990) has suggested that the name 0. lunifer, be restricted to groundnesting populations in eastern Australia, the name has been used by other authors t o describe the canopy-nesting bag-shelter moth (van Schagen et al 1992). Although adults of the bag-shelter moth are structurally similar to those of the bunny-tailed moth (Common 1990), various behavioural and morphological differences exist between the immature stages (Floater 1996a).…”

The guinea pig as a model for Equine Amnionitis and Fetal Loss (EAFL)

“…The eggs hatch into the first larval stage which does not feed. They shed their old skins and develop into second stage caterpillars which are bigger and feed on leaves (Floater, 1996). Before they metamorphose into pupa, the caterpillars need to go through eight developmental stages.…”

“…As the caterpillars are developing, the nest grows bigger with more and more caterpillars shedding their skins (exoskeletons) (Floater, 1996). Sometimes, in the late summer and autumn (April), the caterpillars can defoliate their food tree when they are not fully grown.…”

“…Sometimes, in the late summer and autumn (April), the caterpillars can defoliate their food tree when they are not fully grown. Therefore, they will leave the tree in a long, single procession, following each other head to tail and look for another suitable tree (Floater, 1996). In May, the caterpillars are fully grown and form into small groups (10 or less per group).…”