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Land planarians found on Macquarie Island
Invertebrata 20, July 2001

Terrestrial flatworms have been recorded for the first time from Macquarie Island. Specimens were collected on part of the island distant from the Antarctic Station by Rod Blakemore whilst working on a survey of Macquarie Island invertebrates directed by Penny Greenslade.

One of the two species of flatworms collected belongs in the genus Arthurdendyus that includes five described native New Zealand flatworms; all are earthworm feeders. Arthurdendyus triangulatus and A. albidus have been recorded in the UK as introductions. A. triangulatus has had a well-documented damaging effect on earthworm populations in the UK and the Faroe islands. The new species of Arthurdendyus on Macquarie Island is similar to an undescribed species from the south island of New Zealand, and may be an introduction. It appears that the new species may also be a predator of earthworms as no earthworms were found where the flatworm was present although they are abundant on other parts of the island.

Specimens of the second species found are unfortunately immature, and as yet cannot be confidently assigned to a genus. The morphology and markings of the species are similar to certain flatworm taxa from the New Zealand subantarctic islands, and it is highly probable that the species is native to Macquarie Island.

Leigh Winsor,
School of Tropical Biology
c/- Central Services Office
James Cook University
Townsville QLD 4810
ph (07) 47815418
fax (07) 47252721
Leigh.Winsor@jcu.edu.au

Confessions of a serial sectioner
Invertebrata 20, July 2001

Brian Smith's recent coming out as a specialist suffering from character envy ('The grass is always greener', Invertebrata 19, March 2001) has given me the courage to also confess to this sub-set of one of the seven deadly sins.

I am one of those accursed wretches who, for unknown but evidently horrendous crimes in another life, has been given the genes which arouse my native curiosity in beasts with few external features - terrestrial flatworms. Being parenchymatous beasts, flatworms yield few characters on dissection; they must be histologically serially-sectioned. In taxonomic literature, the words 'histology' and 'laborious' are generally used together. This can be exemplified by 8 mm serial sections of a 70 mm long specimen reduced to 140 microslides, a preparatory task which takes two or three days, with examination and reconstruction taking possibly some weeks to complete, especially in the in the present climate of multiskilled working.

Thus there are indeed times - mercifully few I might add - when I envy those taxonomists who can take the subjects of their interest, and simply view them whole under a lens, optical or scanning electron microscope, and at that level access all the characters necessary for classification. What I particularly envy is the relative ease with which some specialists can, amongst other things, readily assess the variability and reliability of characters for a given species, or confidently identify the species present in a particular sample: in hours and days, rather than weeks or months.

Like many of Brian's molluscs, flatworms have few reliable external features, and even fewer in contracted, preserved specimens. Eye pattern and the positions of body apertures are valuable. Useful but subtle characters in the living animal such as transverse body shape are generally lost in the preserved specimen. Colour and pattern of markings can be extremely variable, and are only reliable in a handful of species. Specimens with the same external markings can, on serial sectioning and reconstruction of their microanatomy, turn out to belong to different genera or species. Conversely, specimens exhibiting widely disparate markings may be the same species in different guises. Tasmanian terrestrial flatworms in particular are good at doing these things.

Only some 20% of the 90 described species of Australian terrestrial flatworms, in a fauna estimated at some 300 species, are presently known anatomically. The challenge of elucidating and describing the microanatomy and the functional histology of these taxa has its frustrations, such as reconstructing often complex copulatory organs, but overall it is very interesting and exciting work. Compensation for serial sectioners like myself is as described by the medical microbiologist Robert Desowitz: '...each time I turn on the microscope lamp, I still feel, like Leeuwenhoek did, like a voyager embarking on a journey to a distant and exotic land.'

Character envy? Yes, sometimes. Bored? Never.

Leigh Winsor
School of Tropical Biology
c/- Central Services Office
James Cook University
Townsville QLD 4810
ph (07) 47815418
fax (07) 47252721
Leigh.Winsor@jcu.edu.au

Editorial
Invertebrata 20, July 2001

Just a short blast this month from the Editor, mainly to thank all our contributors for making Invertebrata 20 a particularly rich feast of interesting reading.

Invertebrata 21 will have coverage of Tasmania's Nature Conservation Strategy (TNCS), which we are advised has now been approved by the Minister and is off to the printers. The November issue will also report on this month's joint conference of the Society of Australian Systematic Biologists and the Australian Evolution Society.

Wingless Tasmanian snow fleas (Mecoptera: Apteropanorpidae) were featured in previous issues of Invertebrata (November 1997 and March 1999). Readers may have gotten the idea from those articles that Apteropanorpa is rare. Dick Bashford now reports that eight of his IBOY pitfalls on Mt Weld (see article) have so far yielded several thousand specimens!

Historical footnote
Invertebrata 20, July 2001

Bridport, 94 years ago:

There are two little creeks in the near neighbourhood; the Brid, which flowed quite near the settler's house into the bay, and Muddy Creek a tiny rivulet about two miles to the east. In these two creeks we used to fish for Black-fish and for Crayfish, or Freshwater Lobsters as the settlers call them... Besides fishing with a line for Black-fish we used to lower lobster-pots, baited with raw meat, for the large freshwater Crayfishes (Astacopsis Franklinii)..., which inhabit the creeks and rivers of northern Tasmania. This Crayfish is the largest in the world, and is quite a distinct species from the small Crayfish which is found in the creeks of the southern part of the island, and which never grows to more than five or six inches in length. The northern Crayfish grows to nearly two feet in length, and may scale eight or nine pounds, competing in size with our marine Lobster; it is dark-green in colour, and studded on the claws and gill-covers with blunt tubercules; the claws of the larger specimens are formidable weapons about the size of a man's hand. We obtained the largest specimens from Muddy Creek, a small rivulet that one could easily step across, and it seemed extraordinary to fish these huge monsters out of little pools in which one would expect to find nothing larger than a minnow. All these Crayfishes were smothered with a parasitic Flat-worm (Temnocephala), about a quarter of an inch long, which were present in such numbers, as to appear like a green foam covering the animal. The freshwater Crayfish or Lobster is excellent to eat, being less coarse than the marine Crayfish (Panulirus), which is the chief commercial Crustacean of Australia; but owing to the difficulties of catching it, it never appears in the fish markets, and the only people who eat it, or know anything about it, are a few prospectors and bushmen.

pp. 108-110 in Smith, G. (1909)
A Naturalist in Tasmania.
Oxford: Clarendon Press

Note: English zoologist Geoffrey Smith spent the summer of 1907/08 in Tasmania. At the time of Smith's visit all large Tasmanian freshwater crayfish were called A. franklinii. In 1936 Astacopsis was split by Ellen Clark into A. franklinii (West Coast and Southwest), A. tricornis (eastern Tasmania) and A. gouldi (north coast, the largest species).

Clark, E. 1936. The freshwater and land crayfishes of Australia. Memoirs of the National Museum of Victoria 10: 5-58.

Hamr, P. 1992. A revision of the Tasmanian freshwater crayfish genus Astacopsis Huxley (Decapoda: Parastacidae). Papers and Proceedings of the Royal Society of Tasmania 126: 91-94.

Invertebrates in the media
Invertebrata 20, July 2001

Rare species nesting near Windsor Castle

Any entomologists on their way to or returning from Royal Ascot this week might care to investigate a rare species discovered in Windsor Great Park last week.

Nests of poisonous rusty red and black spiders, with a leg span of up to 9 cm, were discovered by British Telecom engineers laying underground cables.

A scientist says they may be a species thought extinct or a new species, and described it as 'an extremely exciting find.'

'The species is certainly venomous and the jaws are strong enough to penetrate the human skin,' said Graham Smith, a member of Project-ARK, which aims to preserve the endangered species.

'Who knows how long these spiders have been in the royal park because they live underground.'

'There could be literally thousands and thousands, and it would be no surprise if they are living underneath Windsor Castle itself.'

A British Telecom spokesman said: 'They're large and there's a lot of them. Our engineers were not attacked, but we have stopped work at the site until we know exactly what they are.'

Attempts to fumigate the spiders could be illegal if they are found to be a preserved species and would spread them further afield, Mr. Smith claimed.

BBC online news, Tuesday 16 June 2001
www.bbc.co.uk/londonlive/news/june/spiders_190601.shtml
(Many thanks to Niall Doran for this item. - Ed.)

Notice that even a 'Queen Menaced by Giant Spiders!' story is tempered these days by cautions that the spiders might be threatened and in need of conservation. The UK public, at least, are getting media messages like bugs are interesting and biodiversity preservation is an environmental issue, although the headline might have been designed to lure the bird-fanciers.

And what about Australia? Any evidence that messages like those in the BBC story are getting through? It's hard to judge, but a report from the Community Biodiversity Network (Glanznig 2000) makes discouraging reading:

Australians still have a very low awareness of the term, biodiversity, and a poor understanding of the concept. A national AC Nielson phone poll undertaken in 1999 on behalf of Environment Australia found that while about 4 in 10 Australians thought they had heard of the term, only 1 in 10 understood the concept. The remainder thought the term was concerned with financial planning (buy-diversity) or alternative lifestyles (bi-diversity) (AC Nielson 1999). Recent focus group research suggests that most of those that understood the biodiversity concept had learnt about it through the school or university system (Consumer Contact 1998, p. 20).

This 1 in 10 awareness rate has remained static since the early 1990s when a major national quantitative study found that the term, 'biodiversity', remains virtually unknown (ANOP 1993). Additional social research undertaken in 1993 ascertained that where there is awareness, it tends to be associated with conservation. This qualitative study found that most participants thought that biodiversity was vaguely related to plants and animals, with a stronger association with animals. Insects and bacteria, either as species or as part of an ecosystem, was rarely raised, even after prompting (Michael Gill and Associates Pty Ltd 1993).

A particularly hard message to get across is that invertebrates dominate every accepted measure of Australian biodiversity. They lead in species diversity, genetic diversity, community diversity, evolutionary potential, number of ecological interactions, etc. The 'Mortein'-wielding housewife might not like them, but Nature does. Australian biodiversity consists largely of bugs.

Biodiversity promoters know all about invertebrate dominance, but they're also aware that their audience has been culturally conditioned to abhor bugs. It's for this reason that Australian biodiversity posters typically feature frogs, birds and big-eyed little forest animals - which, ironically, are either constant or occasional predators on invertebrates.

The superbly illustrated magazine Nature Australia, published by the Australian Museum, regularly includes excellent articles on Australian invertebrates. It also has a page with 'thumbnails' of the front covers of back issues. Twenty-four front covers are shown in the autumn 2001 Nature Australia. The subject tally is birds 10, mammals 9 (including two with humans), frogs 2, lizards 1, fish 1 and dinosaurs 1. Two years ago we contacted the editor of Nature Australia to ask why the magazine did such a good job of promoting invertebrates in its pages and such a poor job on its cover. In reply, the editor said that the choice of a subject for the cover was a highly critical decision that makes or breaks sales. Experience shows that bugs don't sell.

A similar distortion of the reality of biodiversity can be seen on the widely distributed poster promoting Tasmania's threatened species. Invertebrates outnumber vertebrates two to one on the State list, but you wouldn't guess so from looking at the poster (q.v.).

The difficulties involved in promoting invertebrate biodiversity were very competently discussed in four papers published by Australian zoologists in 1999 (see references below). Various strategies have been suggested for getting more favourable stories on invertebrates in the major media. What seems clear is that linking bugs are interesting to biodiversity preservation is an environmental issue is not a particularly smart gambit in a country largely ignorant of biodiversity.

Further information:

Glanznig, A. 2000. Australians' Current Awareness and Understanding of Biodiversity and the Issues Confronting its Conservation. http://nccnsw.org.au/member/cbn/projects/CommunicatorsCentre/Comm_Aust.html.

Ponder, W. and Lunney, D., eds. 1999. The Other 99%. The Conservation and Biodiversity of Invertebrates. Mosman (NSW): Royal Zoological Society of New South Wales. See:

Horwitz, P., Recher, H. and Majer, J. Putting invertebrates on the agenda: political and bureaucratic challenges. (pp. 398-406)
Allen, T.J. Building pathways for marine invertebrate conservation. (pp. 407-412)
Smith, R. 'Bugging the media': TV broadcasting and the invertebrate agenda. (pp. 413-417)
White, T.D. Linking amateur and professional observers. (pp. 418-422)

Notices and reviews
Invertebrata 20, July 2001

Moore, J. 2001. An Introduction to the Invertebrates. Cambridge: Cambridge University Press; 355 pp. Paperback ISBN 0521779146, $44.95.

The standard university-level invertebrate zoology texts are over-packed with detail. What hope do beginning students (and lay readers) have of abstracting from the bewildering tangle of facts the broader patterns of invertebrate life? On the other hand, popular books on invertebrates are often little more than 'bestiaries', long on pictures and capsule summaries of individual groups, but short on the biological linkages between higher taxa. Janet Moore's An Introduction to the Invertebrates offers something different: a smartly annotated, comprehensive outline. The writing is clear, simple and to the point. The chapters are organised taxonomically, but within the chapters the topic heads are broad zoological questions, instead of the drearily repetitive '...nervous system, excretory system, reproduction, development, etc' Twelve independent text-boxes deal simply with physiological subjects. The 'Further Reading' chapter is large and heavily biased towards books and papers of the 1990s.

Moore has been teaching invertebrate zoology to Cambridge University undergraduates for many years, and is now officially retired. If you suspect from that information that Moore is the sort of old-timer who snorts contempuously at 'all that new molecular fiddle-faddle,' you couldn't be more wrong. Genetics features throughout the Introduction, its relevance is clearly explained, and there are lucid discussions of the new links between fossil history, molecular phylogeny and developmental genetics. If it's been some years since you studied zoology, and you've never heard of Ecdysozoa and Lophotrochozoa, Hox genes and new interpretations of homology, start here for your update.

Bob Mesibov (Ed.)

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