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.