Print Fact SheetThrips australis

Distinguishing features

Both sexes fully winged. Body highly variable in size and color, from large and generally brown to small and almost white, often yellow with brown area medially on tergites II–IX, segment X brown; antennal segment I white, III yellow, remaining segments largely brown; fore wings pale with dark setae, hind margin shaded. Antennae 7-segmented; segments III & IV slightly constricted at apex each with short forked sense cone; segment VI bullet-shaped, VII short. Head wider than long; two pairs of ocellar setae; pair III arising just within anterior margins of ocellar triangle close to fore ocellus; postocular setae pairs I & III as long as ocellar setae pair III. Pronotum with 2 pairs of short stout posteroangular setae; posterior margin with 3 pairs of setae. Metanotum reticulate medially; median setae arising well behind anterior margin; campaniform sensilla present. Fore wing first and second veins with almost complete row of closely set setae; clavus with 6 marginal setae. Abdominal tergite II with 4 lateral marginal setae, the two anterior setae equal in length; tergites V–VIII with paired ctenidia, on VIII posteromesad to spiracles; tergite VIII posterior margin with comb incomplete medially, about eight teeth laterally; pleurotergites commonly with more than 5 discal setae. Sternite II with 2 pairs of marginal setae, III–VII with 3 pairs. Sternites with many discal setae, 3 on sternite II but 30 on sternite VII, in irregular double rows.
Male smaller and paler than female; tergite VIII with no comb; sternites III–VII with small transverse pore plate anterior to about 10 discal setae.

Related species

T. australis differs from Holarctic species of this genus in having six (or even seven) veinal setae on the clavus of the fore wing, rather than the usual number of five (or four). Some European workers therefore place this species in a separate genus, Isoneurothrips, but several African species of genus Thrips also have six or seven veinal setae on the clavus. The genus Thrips is the second largest genus in the Thysanoptera, and currently includes, worldwide, about 295 species. All members of the genus lack ocellar setae I on the head, and they all have ctenidia on tergite VIII posteromesad to the spiracles. Other characters, such as number of antennal segments, number of setae on the fore wing veins, and number of discal setae on the sternites are variable between species (Palmer, 1992; Nakahara, 1994; Mound & Masumoto, 2005).

Biological data

Breeding in flowers, particularly of Eucalyptus species with white flowers, but also some other Myrtaceae; adults disperse and land on many other plants.

Distribution data

Originally from Australia, but now widespread in areas around the world where Eucalyptus trees are grown, such as Africa as well as South and North America, including California.

Family name

THRIPIDAE - THRIPINAE

Species name

Thrips australis (Bagnall)

Original name and synonyms

Isoneurothrips australis Bagnall, 1915: 592
Thrips lacteicorpus Girault, 1926: 17
Thrips mediolineus Girault, 1926: 18
Anomalothrips amygdali Morgan, 1929: 5
Isoneurothrips marisabelae Ortiz, 1973: 119.

References

Mound LA & Masumoto M (2005) The genus Thrips (Thysanoptera, Thripidae) in Australia, New Caledonia and New Zealand. Zootaxa 1020: 1–64.

Nakahara S (1994) The genus Thrips Linnaeus (Thysanoptera: Thripidae) of the New World. United States Department of Agriculture. Technical Bulletin 1822: 1–183.

Palmer JM (1992) Thrips (Thysanoptera) from Pakistan to the Pacific: a review. Bulletin of the British Museum (Natural History) Entomology Series 61 (1): 1–76.