Field of Science

Score One for Biogeography

Gagrella cauricrepa, the new gagrelline from northern Queensland. Specimen photographed by yours truly (offhand, I think that in over two years, this may be the first time that I've used one of my own images on this site. Now you know why).

One morning as I was sitting down to morning tea shortly after I first arrived in Perth, I made the comment that it was very strange that no Gagrellinae had been recorded from Australia*. Species of the subfamily have been described from both New Guinea and the Solomon Islands, so one would expect to find them here as well - New Guinea and Australia were connected in very recent history, so in biogeographic terms the Torres Strait generally has not functioned as a barrier. Most organisms that are found on one side are also on the other. Why not gagrellines? Yesterday, I had a paper (alluded to in the earlier post) published that solves the mystery by establishing that there is no mystery at all. Gagrella cauricrepa Taylor, 2009 is the first species of Gagrellinae described from Australia. Maybe (more on that later).

*I hasten to note that I was at the museum at the time. I'm not normally in the habit of bringing up random enigmas of arthropodological biogeography in mixed company.

Gagrella cauricrepa is found in the Iron Ranges, which are located right near the northern end of the Cape York Peninsula (the pointy bit at the top end of Queensland). The location in the Iron Ranges also offers a neat explanation as to why Australian gagrellines are not more widespread - it is one of the few patches of true wet rainforest in Australia (most of the remaining forest on Cape York Peninsula is drier), so it is probably the shortage of suitable habitat that holds back the gagrelline advance. Torres Strait itself was no barrier at all*.

*Offhand, despite the universal recognition of the biogeographic identity between northern Queensland and southern Papua New Guinea, I found it surprisingly difficult to find supporting references for it. Few people bother to document what they think everybody knows.

Readers of my earlier post may raise an eyebrow at my placing the new species in the genus Gagrella. All I can say in my defense is that while I know that doing so was a completely stupid, senseless thing to do, all my other options were even more stupid and senseless. The paper does include a discussion of how stupid and senseless I was being.

One thing that you may not realise when reading the paper, on the other hand, is just how close I came to potentially making a prat of myself when writing it (you know, I could have quite easily kept my silence on this subject, but instead I will cheerfully dance for your amusement). My description of the first recorded Australian gagrelline had been submitted, reviewed, revised and was ready to print. Until, only a few days after submitting the final revisions, I was pulling stuff out of Roewer (1910) for the still-in-prep-and-probably-will-be-for-some-time-yet nomenclator, when I saw that Roewer's (1910) description of the new species Zaleptus marmoratus gave the locality as "Australien?" I had been scooped by some ninety-nine years! That was the reason behind the post on Maison Verreaux, who were the source of the Zaleptus marmoratus type specimen. I had not noticed any other gagrellines from Australia in any of the collections I went through, and as it turned out the reputation of Maison Verreaux for supplying specimens with sloppy if not entirely fabricated locality data means that the origin of Zaleptus marmoratus cannot be accepted unquestioningly. No other species of Zaleptus has been recorded east of Sumatra - even if Roewer's Zaleptus is not a monophyletic group (which is probably quite likely), I think the absence from the area of species of a 'zaleptean' morphology still counts for something in this case.

As explained in the paper, I also wasn't able to find any indication that Jules Verreaux (the only member of Maison Verreaux to visit Australia) had been far enough north in Queensland to be collecting gagrellines. This conclusion is somewhat more shaky - Jules himself never wrote an account of where he had been (I'm guessing that he probably didn't want to leave a paper trail), so I was dependent on other people's records ("Australia" was about as specific as a Verreaux label got). But in concert with the point that Jules' brother Édouard definitely was in south-east Asia in the early 1830s*, near where 'Zaleptus' species have been reliably recorded, I suspect that an Asian rather than Australian origin for Z. marmoratus is at least possible, if not really demonstrable in the absence of specimens other than the holotype. So while Gagrella cauricrepa may not be the first record of Gagrellinae from Australia, it is the first reliable record from Australia.

*Contrary to what I said in the paper, it seems likely that Édouard travelled in south-east Asia more than Jules. My potted summary of their movements relevant to Z. marmoratus (written rather hastily, so as not to lose the deadline) was drawn heavily from Jules Verreaux's obituary in The Ibis. Unfortunately (but perhaps fittingly), the Ibis obituary seems to have been misleading about a number of things. In particular, it states that:

In 1832 Jules Verreaux again summoned his brother to join him [in South Africa], and till 1837 they travelled together, making expeditions to the Philippine Islands and Cochin-China. In 1838, having amassed large collections, the brothers shipped their treasures on board the trading-vessel ‘Lucullus’, they themselves embarking in another ship bound for France. Most unfortunately the ‘Lucullus’ was totally lost; and the labours of several years, uninsured, perished with her.

In my paper, I interpreted this to mean that both brothers arrived in Asia in 1832, remained there until 1837, but lost all their Asian material when the 'Lucullus' sank (which would be something of a problem for an Asian origin of Z. marmoratus). However, going by other references (see the Maison Verreaux post, which was written later than the Gagrella cauricrepa paper), it seems more likely that one, the other, or both brothers together made a number of trips between Asia, Paris and/or South Africa between 1832 and 1837, and that when Jules Verreaux was returning to Paris with material shipped on the 'Lucullus', he was returning from South Africa, not Asia (frustratingly, I haven't been able to find anything that says exactly where the 'Lucullus' had left from). It says something about the difficulty of tracing a person when you can't even be certain what continent they were on.


Taylor, C. K. 2009. Revision of the Australian Gagrellinae (Arachnida: Opiliones: Sclerosomatidae), with a description of a new species. Australian Journal of Entomology 48: 217-222.


  1. Congratulations Christopher! It took me a while to work out the orientation of the beastie in your photograph, but as my best friend (who works on gastropod morphometrics) will attest, I'm lost without a notochord.

    We share a common problem - the "It has long been known that" syndrome, where no one bothers to cite references for something that was probably written down 100 years ago by someone who'd had a bit too much gin and not enough peer review!

  2. As always, nice post ;)!

    Is Gagrella cauricrepa exclusive of Australia? In that case Torres strait, may be a barrier!

    I look on some Heads papers. I am not a panbiogeographer, but it seems that he shows several evidence of a vicariant pattern between New Guinea and Australia... so that is evidence for the Torres strait as barrier!

  3. Julia - the end with the eyes is usually the front.

    Salva - at the moment, Gagrella cauricrepa is only known from northern Australia. The problem is that records of harvestmen (and most other animals) in New Guinea are very spotty and localised, so it's difficult to say anything definite about most distributions.

  4. 16th International Congress of the International Union of Anthropological and Ethnological Sciences (IUAES)

    By Drs Aris and Daphne N. Poulianos
    Kunming, China 31-7-09

    The title of this paper may sound a little deterministic, but I am convinced we human beings went through a longer period of hominization, than usual historians, including marxists, allow to conclude today.
    We definitely come from apes, but not African ones. Once upon a time lived in Europe over fifty species of monkeys. But an ape, which I named Helladopithecus semierectus, lived on trees, seventeen million years ago (ANTHROPOS, V3, N01, Jan. 1976, pp3 – 30, Athens).
    The well known Pikermi fauna of the Miocene period is found from Hungary through Balkans to Iran: (Wagner, A1840: Fossile Uberreste Von einem Affen und anderensau getierren aus Griechenland. Abh. Bayer. Akad. Wiss, 3, Munchen). Among other finds, a very important of that period was Mesopithecus pentelici, whose range also extended over a large territory, beyond Greece, and which is known to be a terrestrial monkey. It’s wide extension over a large territory, presupposes, that some anthropomorphic monkeys could ’’descend from trees’’ (Roghinski, J.J. & M.G. Levin, 1963: Anthropologhia, Moskva, str. 184 – 185), and begun to walk. Consequently among those “descenders” could be some andecedent forms of man.
    Another lower jaw from Attica found by a german officer during the years of occupation (1942) and described by G.Von Koenigswald, (1972: Einunterkiefez eines fossilen Hominoiden aus dem unterpliozan Griechenlands. Konikl. Nederl. Akademie Van Wetenschappen. Series B, 75, No 5, str. 385 – 394, Amsterdam), seems to be an advanced form which does not belong to Dryopithecinae, and which might also represent the beginning of African Primates. Koenigswald gave him a not very successful name “graecopithecus”. Its age is about 9 million years old. The lower jaw of another specimen found by the French expedition in 1972 near Thessaloniki, was named Dryopethicus macedoniensis. But it is also of a more advanced type than the Dryopithecinae, and according to Koenigswald is more closely affiliated with the hominids. Its age is Upper Miocene (Vallesian).
    Finally, the find described in this paper (Helladopithecus), is the upper part of a left femur found by our expedition in 1974 near Tharounia, a village in the island of Euboea. The age established lately, is Lower Miocene, about 17 million years old, confirmed by its stratigraphy, as well, and kept now in the Anthropological Museum of the Archanthropus man at Petralona, Chalkidiki.
    It is fully described and decided to be a semierectus monkey, as these authors call the whole complex of similar finds from Attica and Makedonia too.
    The new bone find is 98 mm. long (given the signal name ‘’A.E. – 1’’, seems to belong to a rather young individual, and its whole length (proportionally counted) cannot be more than 350 mm. That is the standing height should be about 140-150cm. Its weight, according to Debetz index (ICVS), approximately should be about 40-42 klgms. The stoutness index then is about 22, 85 (the same index for Orang, Chimpanzee and Gorilla, being 32-33, while for man is 18-21.

  5. 16th International Congress of the International Union of Anthropological and Ethnological Sciences (IUAES)

    But among all these indirect methods of identifying a find, the best would be to measure exactly the Torsion angle, in order to establish the percentage of its erect position. Thus a new method was developed to measure the torsion angle in a broken femur bone. This method is based on the assumption that the torsion angle (Θ) of a bone is directly proportional to the angle of its cylindrical surface (α). (See designs 2 and 3). The axis of a bone is the line passing through all gravity centers of all its side section (AB). The edge of the cylindrical surface of a bone is the line uniting all corresponding corners of the cross – section (ΓΔ). That is: θ=Κ.α, where Κ – proportionality coefficient.
    And this assumption is based on
    a)the geometrical similarity of corresponding bones of different animals.
    b)The physico-chemical similarity of bones, and
    c)On the approximately constant ratio between animal weight and cross-sectional area, that is the stress of bone loading is almost constant (the animal weight per unit of cross-sectional bone area).
    In order to find Κ we take a similar unbroken contemporary bone, and measure its angles θ and α:
    Κ= θ. Unbroken / α. unbroken
    Then we measure the angle α of the broken bone and find angle
    θ.broken = K.a unbroken = θ. Unbroken . α. broken / α. unbroken
    Angle α is the average of angles β & γ.
    The angles β & γ can be found by photographing the bone and measuring these angles on the picture. In order to make edge ΓΔ clearly distinguishable we illuminate the bone from the side. Then ΓΔ becomes the border line of two differently illuminated surfaces. In our case we took 17 differently oriented pictures of both bones, broken and unbroken (see pictures in the text and table 1).
    The result of these procedures showed that θ (torsion) broken = 18ο , which means that this monkey was about 65% erect during his lifetime. That means he was pretty much erect, certainly more erect than most today’s African primates. Thus, it is concluded, Helladopithecus could be the forerunner of Homo.
    Finally, we raise to the rank of a separate family the whole complex of Helladopithecus finds from Greece, classifying it right after the Hominid family. As a result of the above process we have the first standing man on earth, Homo erectus trilliensis, spreading all over the world from this region of the Aegean, of the SE of Europe 13 million years ago.
    The over one hundred years long discussion among anthropologists (‘’polyphyletic versus monophyletic origins’’) sounds is ending. Monophyletic origin of man (from Helladopithecus to Homo erectus trilliensis) to our opinion is more or less confirmed who spread from Atlantic to Pacific and then all over the rest of the world. It seems every biological species on earth develops from one center, and then it spreads all over.
    In the mean time excavations are going on: A new find, a part of the skeleton of a young girl of 14 years old was found. The find was named Homo erectus trilliensis Daphnae, after the name of the lady present in this hall Mrs Daphnae A.Poulianos.

  6. Don't know about arachnids, but land snail distribution is a bit weird. Generally there's not much overlap between NG and Aust below family level. Among the camaenids, two genera of tree dwellers occur in both places. Both genera (Meliobba, Rhynchotrochus) are represented by single sp in Aust but rather more in NG.

    What's odd about them is that neither is known from either Iron Range or the McIlwraith Range on Cape York Peninsula. The genera occur throughout New Guinea and then pop up in the Wet Tropics, with a dirty great big gap in the middle. I've also seen some odd-looking snails from Iron Range and McIlwraith Range that look quite different from other species in Aust. Something strange seems to be happening as far as the molluscs are concerned.

    (Mind you, that something strange could be the result of under-collecting. I am willing to retract everything!)

    BTW, I've got a pic of a opilionid to send you. Hope I put it somewhere easy to locate on the hard drive.


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