FNZ 10 - Tubulifera (Insecta: Thysanoptera) - Diagnosis, Phylogeny, and Systematics
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
Diagnosis, Phylogeny, and Systematics
The suborder Tubulifera includes rather more described species (2700) than the Terebrantia (2000) (Mound et al. 1980). Moreover, since the Tubulifera exhibit a wider range of biologies, and frequently occupy relatively concealed ecological niches, this difference is likely to increase rather than decrease with expanding knowledge.
Adult Tubulifera can be distinguished from Terebrantia by the following characteristics.
- Forewings (Figure 150), when present, without veins although sometimes with a longitudinal dark line; usually only three setae present, near base; membrane never bearing microtrichia; marginal cilia straight, arising directly from membrane, never independently socketed.
- Abdominal segment X (Figures 277-286) tubular, but varying in shape from short and conical to long and slender; terminal setae not arising from surface of tube, but arranged in a circle around the anus; base of tube emarginate ventrally in male.
- Female with an eversible ovipositor emerging at base of tube; eggs deposited on surface of substrate.
- Maxillary stylets usually elongate, extending deeply into head, often reaching almost as far as compound eyes (Figure 43), rarely restricted to mouth cone (Figures 71 - 74).
- Development from egg to adult involves two larval and three pupal instars (Figures 2 - 6).
The phylogenetic relationships of the Tubulifera are still unresolved. Only a single family, the Phlaeothripidae, is recognised in this group. Mound et al. (1980) suggested two possible evolutionary scenarios: either the Terebrantia as a whole is the sister-group of the Phlaeothripidae, in which case this family is ancient, or the sister-group lies within the thripid subfamily Panchaetothripinae of the Terebrantia, in which case the family is relatively recent in origin. Although the first possibility is generally accepted, as indicated by the recognition of two suborders, there is no good evidence to support it. However, the second possibility is difficult to accept on morphological grounds. No thrips has ever been discovered which could possibly be considered as a 'primitive' member of the Phlaeothripidae, and whereas Terebrantia are common as fossils in amber, with several extinct taxa represented (Zur Strassen 1973), the few fossil Tubulifera found have all been very similar in structure to existing species. For the present, the classification into two suborders is accepted for practical reasons, despite the possibility mentioned above that the Phlaeothripidae arose from panchaetothripine ancestors, presumably by neoteny in a subcortical habitat.
Within the Phlaeothripidae two subfamilies are recognised, the Phlaeothripinae and the Idolothripinae. The latter is much the smaller, with only 600 species world-wide, all feeding on fungal spores. A revised generic and suprageneric classification of these species (Mound & Palmer 1983) recognises only two tribes, Pygothripini and Idolothripini, and nine subtribes. With the exception of the Australian immigrant Idolothrips spectrum, the New Zealand spore-feeding thrips are all Pygothripini.
The subfamily Phlaeothripinae includes more than 2000 species, and their generic and suprageneric classification is particularly difficult. Priesner (1961) recognised 10 tribes (Plectrothripini, Haplothripini, Phlaeothripini, Hoplothripini, Glyptothripini, Hyidiothripini, Leeuweniini, Emprosthiothripini, Terthrothripini, and Rhopalothripini), and an additional subfamily, Urothripinae. Moreover, he recognised 5 subtribes in the Phlaeothripini and 13 in the Hoplothripini. Most of these groups, other than the monobasic ones, were poorly characterised. Subsequent authors have found the classification largely unworkable, although it continues to be accepted in part and without any reappraisal (Ananthakrishnan 1969b, Schliephake & Klimt 1979).
Priesner's classification was published largely in reply to a well argued scheme of relationships propounded by Stannard (1957), although this author had not proposed any formal suprageneric classification. Stannard recognised a series of nine phyletic "lines", most of which are reflected in Priesner's formally named tribes. Thus, Stannard's Haplothrips, Glyptothrips, Plectrothrips, and Hyidiothrips lines correspond to the four tribes listed above bearing these names. Moreover, his Amphibolothrips line corresponds to the Urothripinae, his Gigantothrips line corresponds to the Hoplothripini with the exclusion of Hoplothrips itself, and his Neurothrips line corresponds to the Phlaeothripini with the addition of Hoplothrips. Finally, Stannard's Docessissophothrips line is now recognised as a tribe (Mound & Palmer 1983). This leaves only his Williamsiella line, including Sophiothrips and Lissothrips, in dispute.
Of the ten tribes recognised by Priesner, Emprosthiothripini was transferred to Idolothripinae and synonymised with the Pygothripina by Mound & Palmer (1983), and Terthrothrips, the only genus in the Terthrothripini, is now placed in Glyptothripini, a group of mainly Neotropical leaflitter species (Mound l977a). Moreover, Urothripinae is now treated as a tribe (Mound 1972a), and the two genera placed in Rhopalothripini seem to be more closely related to the genus Hoplothrips. The only additions to the tribal classification in recent years have been two groups transferred from the Idolothripinae by Mound & Palmer (1983), the Apelaunothripini and the Docessissophothripini.
Thus, 10 tribes might still be recognised in the Phlaeothripinae, of which five are represented in New Zealand (Haplothripini, Hoplothripini, Phlaeothripini, Plectrothripini, and Urothripini). However, because of problems in differentiating the Hoplothripini and the Phlaeothripini, which together include most species and genera of the Phlaeothripinae world-wide, no attempt is made here to use the tribal classification. Haplothripini is discussed under Haplothrips, Plectrothripini under Plectrothrips, Urothripini under Baenothrips, and Hoplothripini and Phlaeothripini under Hoplothrips. The five remaining tribes (Apelaunothripini, Docessissophothripini, Glyptothripini, Hyidiothripini, and Leeuweniini) all seem to be represented in Australia.