OzThrips

Thysanoptera in Australia

Recognition data

Distinguishing features

Female macropterous. Body light brown, legs and antennal segment III yellowish; fore wing pale, weakly banded with diffuse shading medially and at extreme apex.

Head with postocular region about as long as eye length; one row of postocular setae, pair II not displaced posteriorly out of line, II and V scarcely longer than I, III and IV; 3 pairs of ocellar setae present, pair III within ocellar triangle posterior to first ocellus, shorter than median length of posterior ocelli;  maxillary palps 3-segmented. Antennae 9-segmented, III with two greatly inflated sensoria occupying more than 50% of inner apex, IV usually with 2 conical sensoria, V–VII with one ventral emergent sensorium; IX elongate with several transverse lines. Pronotal posterior margin with row of about 6 moderately prominent setae; one pair of setae dorsal to but scarcely 0.5 as long as posteroangular setae. Mesonotum medially with one pair of small setae. Metanotum with many sculpture lines concentric around posterior third of sclerite; metathoracic furca with no median spinula; metathoracic sternopleural sutures well-developed. Abdominal tergite I with faint transverse lines medially; trichobothria on X slightly larger than base of major setae; sternites with 3 to 4 pairs of marginal setae, no discal setae; VII strongly emarginate medially the 2 pairs of accessory setae arise on margin (thus apparently 5 pairs of marginal setae).

Male similar to female but varying in size from larger to smaller than female. Abdominal tergite I with two longitudinal ridges; large males with 2 pairs of stout spindle-shaped setae on IX; sternites with no discal setae.

Related and similar species

The genus Cycadothrips is known only from Australia, with three described species. Each of these varies greatly in size, particularly the males, but all three are very similar to each other in structure despite occuring in widely separated parts of the continent. On antennal segment III in C. chadwicki the paired sensoria are larger than in either of the other two species in this genus, occupying almost half of the apex of this segment. .

Distribution data

General distribution

Known only from Australia

Australian distribution

Apparently widespread in the coastal forests of eastern Australia, from South of Sydney to North of Brisbane.

Biological data

Host plants

Breeding in the male cones of Macrozamia lucida and related species (Zamiaceae) (Forster et al. 1994; Terry, 2001)

Life history

Adults and larvae occur in vast numbers in the male cones of their host-plant, and adults are attracted to the female cones which they enter and effect pollination (Terry et al., 2005).

Taxonomic data

Current valid name

Cycadothrips chadwicki Mound

Original name and synonyms

Cycadothrips chadwicki Mound, 1991

Oz thrips taxa