FNZ 10 - Tubulifera (Insecta: Thysanoptera) - Distribution and Faunal Relationships
Mound, LA; Walker, AK 1986. Tubulifera (Insecta: Thysanoptera). Fauna of New Zealand 10, 144 pages.
(
ISSN 0111-5383 (print),
;
ISBN 0-477-06784-0 (print),
).
Published 22 Sep 1986
ZooBank: http://zoobank.org/References/0C947CDE-29D0-411A-8AB1-E16C06255989
Distribution and Faunal Relationships
Most of the 68 species of Phlaeothripidae recorded from New Zealand are known only from a few specimens from scattered populations, and this makes it difficult to deduce their real distributions. Only Nesothrips alexandrae appears to be localised within New Zealand, and this seems to be a Central Otago form of the common and widespread species N. propinquus.
Although Phlaeothripidae have been collected over a wide range of altitudes, only Teuchothrips annulosus appears to live normally as high as the tree-line, where it is associated with the shrub Cassinia vauvilliersii. Another distribution pattern for which there is more evidence is the contrast between Nothofagus and Podocarpus forests; remarkably few thrips are found in the latter. Similarly, differences can be observed between forest with a complete canopy, in which Ozothrips priscus is often common, and forest with a disrupted canopy, in which O. eurytis is more typical. Habitats dominated by adventive plants do not usually harbour native thrips, although Anaglyptothrips dugdalei has been collected only under such conditions.
Faunal relationships of the New Zealand Phlaeothripidae have proved even more difficult to assess than those of the Terebrantia (Mound & Walker 1982c). The endemic species cannot be distinguished satisfactorily from the introduced fauna, primarily because this family is both large and poorly studied in surrounding geographical areas. Of the 68 species of Phlaeothripidae recorded here from New Zealand, 27 are known also from elsewhere, 17 of them only from Australia (including Tasmania). In addition, Nesothrips propinquus is clearly a member of the New Zealand fauna, but is now widespread in Australia and along the old shipping route to Europe (Mound 1983). Moreover, Hoplothrips semicaecus (including its synonym H. fieldsi), which has previously been regarded as Holarctic, is here considered to be a New Zealand species introduced to the Northern Hemisphere. Thus, only eight Phlaeothripidae are considered to have been introduced to New Zealand from outside Australia. Three of them are widespread in the Northern Hemisphere (on lily bulbs, clover, and orchard trees), and the other five live on fungi on dead wood (three are European, two Oriental). This apparent lack of immigrant Tubulifera species is remarkable, particularly in view of the number of immigrant Terebrantia (Mound & Walker 1982c) and the number of tramp species known from the Pacific islands (Mound & Walker 1986).
Several of the species shared with Australia are evidently immigrants from that country. These include Idolothrips spectrum, which is abundant in Australia but is known from only one specimen in New Zealand; Teuchothrips disjunctus, the host plant of which is an introduced garden shrub from Australia; and Baenothrips moundi, Emprosthiothrips bogong, and Sophiothrips greensladei, which have relatives in Australia but not in New Zealand. Natural transfer of such small insects on winds across the Tasman Sea is evidently not uncommon (Mound 1983), and successive invasions possibly account for some of the taxonomic problems referred to below in the leaf litter species of the genera Psalidothrips and Deplorothrips. Other species may have been transported inadvertently by man in the opposite direction. For example, Heptathrips cumberi has no close relatives in Australia but is a member of a New Zealand species group. This may also be true of Apterygothrips australis, Hoplothrips poultoni, Carientothrips loisthus, and C. badius, although these are difficult to place with certainty in either fauna.
The 43 species of Tubulifera endemic to New Zealand represent a markedly higher proportion of the fauna than the 19 endemic Terebrantia (Mound & Walker 1982c). Amongst the Idolothripinae the genera Cleistothrips and Ozothrips, and most species of Heptathrips, are endemic to New Zealand, and it is interesting to note that these genera are regarded as being among the most primitive members of the subfamily (Mound & Palmer 1983). In addition, the species of Nesothrips dealt with here are all endemic to New Zealand, although this genus is widespread in the Pacific and Australia. Amongst the Phlaeothripinae, the species of Apterygothrips, Hoplandrothrips, Hoplothrips, Lissothrips, and Sophiothrips dealt with here are mainly endemic, although these genera are all found in other parts of the world. Despite this endemicity, some species known so far only from New Zealand - including Anaglyptothrips dugdalei, Azaleothrips neatus, Haplothrips salicorniae, and possibly Yarnkothrips kolourus - may eventually prove to be introduced. Moreover, the species of Psalidothrips in leaf litter may all be natural immigrants from Australia, although Deplorothrips appears to be endemic, judging from the structural variation within and between its populations.