Field of Science

Secret Identities

A couple of days ago, I asked if you could guess the identity of organisms previously placed in quite different taxonomic positions from the ones they occupy now (if you haven't done it yet, click on the link and have a go before you come back here). And here are the answers:


1. Vorticella cincta Müller 1773 = Peridinium cinctum (photo by Kate Howell).

Psi got this one, but her assumption that a dinoflagellate was being mistaken for a ciliate is not entirely accurate. Vorticella cincta was one of the very first two dinoflagellates to be named; both were described as ciliates. Dinoflagellates possess two long cilia (or flagella, if you prefer), and carry one of the cilia wrapped around themselves in a groove (it is the movement of this wrapped cilium that gives dinoflagellates their characteristic twirling movement*). Early microscopists, who could probably see the movement in the groove but not make out the actual cilium, thought that the groove was a band of small individual cilia as found in ciliates.

*Come to think of it, maybe that's why dinoflagellates do everything so strangely - their constant spinning has left them so disoriented that they can no longer tell good sense from bad.



2. Helix smaragdus Martyn 1784 = Turbo smaragdus (photo by Graham Bould).

Turbo smaragdus is the ultra-common cat's eye shell of New Zealand (the common name refers to the pattern of the operculum). Early mollusc systematists tended to use a very small number of large genera; indeed, I've occasionally been driven to wonder if some of them recognised only two genera of gastropods - Helix for everything with a shell, Limax for everything without. Molluscs are one of the worst groups of organisms (ferns are probably the other) for what I've dubbed the "Evil Old Genus" effect. Evil Old Genera are those that have included a very large number of species over their history, most of which have since been placed in other genera, making synonymies and homonymies an absolute nightmare to keep track of. (The most evil of Evil Old Genera, perhaps, is the neogastropod Pleurotoma; Pleurotoma has been used for hundreds of species, but what makes it really ghastly is that Pleurotoma has the exact same type species as Turris, an older name by a year, so Pleurotoma is not even a valid genus.) The main reason for the initial conservatism of molluscan taxonomy was that it was then based almost entirely on shell morphology only; it would not be until later that malacologists decided that it might be interesting to look at the squashy bits inside the shell as well. True Helix as currently recognised is a terrestrial pulmonate snail; Turbo belongs to a very different group of gastropods, the marine vetigastropods. For comparison, the two are probably less closely related than you are to a goldfish.



3. Nautilus radicula Linnaeus 1758 = Nodosaria radicula (photo of Nodosaria bacillum from here).

Linnaeus' original concept of Nautilus actually included more foraminiferans than molluscs. In the eyes of many early researchers, the resemblance in structure of the foram shell divided into chambers to the shell of a microscopic cephalopod indicated that that was just what they were. It took until the 1800s for the fundamentally different anatomy of forams to be recognised.



4. Phalangium cancroides (Linnaeus 1758) (originally Acarus cancroides) = Chelifer cancroides (photo from here).

This is another case of a genus name originally referring to a much broader concept than today; Linnaeus used the name Phalangium for all arachnids with a segmented abdomen but without the sting of Scorpio. Not just harvestmen, but pseudoscorpions, sun spiders, whip scorpions and amblypygids were placed in Phalangium.



5. Cancer pulex Linnaeus 1758 = Gammarus pulex (photo from here).

Cancer was used Linnaeus not just for crabs, but for pretty much all crustaceans.



6. Asterias bifida Pennant 1777 = the crinoid Antedon bifida (photo from here).



7. Holothuria priapus Linnaeus 1767 = Priapulus caudatus (photo by Marko Herrmann).

To be honest, I'm not sure why this one doesn't still go by Linnaeus' original (perhaps overly descriptive for those of a sensitive nature) name of Priapus humanus ("human dick"). The other species in Linnaeus' Priapus, Priapus equinus ("horse dick"), is a sea anemone. And if you're surprised that Linnaeus should be so crude, try looking up the story behind his name for the marine worm Aphrodita.



8. Gasterosteus volitans Linnaeus 1758 = Pterois volitans (photo from here).

Linnaeus has proved to be a little more prescient in this case that he is usually given credit for. After being placed in separate orders for a great many years, phylogenetic studies are now indicating that the Gasterosteidae (sticklebacks) are in fact nested among the former Scorpaeniformes, of which the lionfish is a member. And while I'm at it, I may as well remind of my earlier reference to observations of lionfish evolution in action.



9. Vultur fulvus Hablizl 1783 = Gyps fulvus (photo by Aka).

Though you could well argue that this one has gone nowhere. Linnaeus included species of both New World and Old World vultures in the genus Vultur. When it was later recognised that these two groups of birds were in fact not closely related, authors disagreed over whether the name Vultur should be used for the New World or the Old World vultures. In the end, those who used it for New World vultures won out almost by default.



10. Upupa eremita Linnaeus 1758 = Geronticus eremitus (photo by clkayleib).

Bonus points go to Lars Dietz, who not only successfully identified this species but managed to beat me at my own game by telling me the back-story that I didn't even know myself. According to Lars, Linnaeus himself had never actually seen one of these birds, and was describing it from its reputation.



11. Myrmecophaga striata Shaw 1800 = Nasua nasua (photo by Matthias Kabel).

Shaw's identification of this animal as an anteater rather than a carnivoran may be related to the fact that, again, his description seems to have been based on someone else's (specifically, the Comte de Buffon's) illustration of a specimen rather than on the specimen itself. It doesn't help that, if Shaw's illustration is any indication, the specimen was pretty poorly mounted. On the other hand, Shaw's concept of Myrmecophaga also included the aardvark and the echidna, so it was already rather broad.



12. Lemur simiasciurus Schreber 1774 = Potos flavus (photo from here.

Or maybe not. Schreber seems to have used the names Lemur flavus and Lemur simiasciurus ("monkey-squirrel lemur" - great name, no?) as alternative labels for the same species, the animal now known as the kinkajou (a South American carnivoran, not a lemur). And in response to Neil's incredulity that a kinkajou could be identified as a lemur - it's arboreal, it has a curly tail, how much more like a lemur could you want it to be? But to complicate matters, Schreber's supposed illustration of "Lemur simiasciurus" is not a kinkajou, but an actual lemur (Lemur mongoz). Authors have differed as to whether L. simiasciurus was supposed to apply to the kinkajou or the lemur (with perhaps the majority supporting the former, if only by default), but as the name is unlikely to return to use in the either case the question is largely academic anyway.



13. Mus canguru Statius Müller 1776 = probably Macropus giganteus (photo by Di Paice).

Among the specimens Joseph Banks carried back from his stint in Australia as botanist to Captain Cook was one that he described as a "mouse" or "jerbua" even though it differed from the usual run of mice in weighing about eighty pounds. This was the animal that Statius Müller was to refer to as _Mus canguru_ (the popular story that the word "kangaroo" was actually Aboriginal for "I don't know what it is" or "I don't understand what you're saying" seems to be a myth, probably arising from confusion when British colonists tried to use the word in speaking to all Aboriginals even though they wouldn't have recognised the word unless they happened to speak Guugu-Yimidhirr*). Most authors have believed that Banks' "kanguru" was a specimen of Macropus giganteus, the eastern grey kangaroo, and many authors used Macropus canguru as the valid name for that species. Unfortunately, Banks' original description is not detailed enough to be certain of the identity of Mus canguru - it might refer to another Macropus species - and the ICZN eventually suppressed the name in favour of M. giganteus.

*Ellis (2001) refers to a particularly brilliant example of this confusion in a report of Sydney Cove Aboriginals referring to European cattle as "kangooroo", apparently because they thought that it was an English word.



14. Lutra minima Zimmermann 1780 = Chironectes minimus (photo from here).

Not a semi-aquatic carnivoran, but a semi-aquatic marsupial.

15. Viverra cancrivora Brongniart 1792 - This was the only entry that no-one identified correctly. Many of you thought that it might be Procyon cancrivorus, the crab-eating racoon. Nope. Cabrera (1957) listed this name in the synonymy of:



Cerdocyon thous (photo by Rhett Butler).

Not very civet-like, is it?



16. Limax lanceolatus = Branchiostoma lanceolatum (photo from here.

Nor is a lancelet much like a slug.

REFERENCES

Cabrera, A. 1957. Catalogo de los mamiferos de America del Sur. I (Metatheria - Unguiculata - Carnivora). Revista del Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” e Instituto Nacional de Investigacion de Las Ciencias Naturales, Ciencias Zoológicas 4 (1): 1-307.

Ellis, M. 2001. Tails of Wonder: constructions of the kangaroo in late eighteenth-century scientific discourse. In Science and Exploration in the Pacific: European Voyages to the Southern Oceans in the Eighteenth Century (M. Lincoln, ed.) pp. 163-182. Boydell & Brewer.

7 comments:

  1. And if you're surprised that Linnaeus should be so crude, try looking up the story behind his name for the marine worm Aphrodita.

    Oh, do tell! (I can't seem to find anything about this on Google, and don't know where else to look.)

    ReplyDelete
  2. The most evil of Evil Old Genera of mollusks may have been Helix actually. There was a time early in the 19th century when most terrestrial snails were in Helix & the rest, the ones with shells taller than wide, was in Pupa.

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  3. Emily:

    Aphrodita is a small animal with a dense covering of hair, which is commonly known as a "sea mouse". In Sweden, "mouse" also was (and apparently still is) a slang term for a woman's private parts. Hence Linnaeus naming a 'mouse' after the goddess of love.

    Aydin:

    Do you know what the type species of Helix actually is? I would have always thought it was H. aspersa, but evidently it's not. H. pomatia, perhaps?

    ReplyDelete
  4. According to Wikipedia, it is H. pomatia. It couldn't be aspersa, because aspersa is not in Helix anymore.

    ReplyDelete
  5. I can confirm that "mouse" is still used in Swedish for a woman's private parts. Wouldn't characterize it as slangy, tho, more old-fashioned.

    ReplyDelete
  6. Christopher:

    In Sweden, "mouse" also was (and apparently still is) a slang term for a woman's private parts.

    To this I might add that the Swedish word for 'mouse' is spelled mus. How to pronounce that word may not be self-evident to a native English-speaker. But if you pronounce it as you would pronounce the English word 'moose', you won't be very far off.

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  7. I dunno, it's all sounding a little Robbie Burns-ish.

    ReplyDelete

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