Saturday 23 November 2019

Chinese Giant Salamanders: More information on those we had in the lab in 1960s Hong Kong

In the last post I noted how Edward George Boulenger had, in his description of a new species in 1924, noted: ‘Head…very much depressed’. I have found some photographs and videos of Chinese giant salamanders which show a similar appearance to that described by Boulenger but many which do not. Boulenger’s species (which had been regarded as synonymous with Andrias davidianus), Andrias sligoi, has been resurrected as a result of molecular phylogenetic analysis published this year. One can argue whether the species rank is warranted but there seems no doubt that the classic lineage, davidianus is different from sligoi and that they are geographically isolated. All sorts of questions then spring to mind: Is the ‘very much depressed’ head characteristic of the sligoi lineage? Or is it only in that state at a certain stage of growth? Are there other tissues present beneath the skin and bone that give a non-depressed appearance, changed by nutritional state, for example?

I have also looked at photographs of giant salamander skulls and replicas online, and again there do seem to be that remain flat posterior to the eyes while other show a rise in the region of the junction between the frontal and parietal bones.

I remembered that a very flat head described by Boulenger was not a feature of the Chinese giant salamanders bought in alive for class dissection at the University of Hong Kong in the 1960s. I took several photographs (and previously discussed some of them here) and they are shown below. To me the head seems more bulldog-like with a short ‘muzzle’ and, to continue the canine analogy, a ‘stop’— the rise in the skull beginning at the line of the eyes; in other words, the heads of these animals bought from the human food chain did not resemble Boulenger’s sligoi or some of the photographs of live specimens in circulation.



This one had lunged at my wife's hand with mouth open, and is ready to take on all comers


The bulldog-like shape of the head is particularly evident here


















































In the last post I noted the distance between the nostrils in Chinese and Japanese giant salamanders. I did a rough calculation from the photograph above (it had to be rough given the perspective). The distance between the nostrils was approximately 24% of head width, close to 21.5, the mean of five specimens in U.S. museums, detailed by Liu in his book published in 1950.

The pattern of tubercles on the head of our lab specimens is similar to that shown in a drawing in Liu’s book for A. davidianus but not that of sligoi shown in a drawing by or for Boulenger published on the ZSL website.

Is it, therefore, likely that the 1960s Hong Kong specimens were not from the sligoi genetic lineage but one of the other lineages from the mountain ranges of north-western China?

The question is interesting because it would suggest the main source for the trade in live salamanders going through Guangzhow (Canton), said to be the centre of the trade, was not the closer Nanling mountains but the mountains on the edge of the Tibetan plateau to the north and west.

In the old zoology store in the now-demolished Northcote Science Building there were some preserved specimens. My recollection is that there were several giant salamanders of modest size in jars of spirit rather than formalin. Did they survive the grand clear out when the department moved out and then moved on again to the Kadoorie Biological Sciences building? I was told a lot of stuff had been thrown out when I was external examiner in the department in the late 1990s but would somebody please have a look. If they still exist they could add something to the molecular phylogeny research and the pattern of trade for the human food market.

I have been fascinated by giant salamanders ever since seeing my first, the large Japanese one that lived in the vestibule of the aquarium at London Zoo. I never saw it move. The dozen or so for class use in the vertebrate course in Hong Kong were fascinating during the short time they were there. They were decidedly feisty; my wife had to move quickly as salamander wrangler when they made a lunge for her fingers during the photoshoot on the roof of the Northcote Science Building. I know they had to be ordered, with notice when they were needed. Food/Chinese medicinal items often came into Kong Hong from Chinese provinces like Yunnan and Sichuan far to the west in the1960s. There was a shelf of bear paws in the Chinese Merchandise Emporium on Queen’s Road.

We went through giant salamander country in Sichuan two years ago, with roads descending alongside the rocky streams and the slacker water in flatter valleys. Unfortunately, because many of us would like to have seen the set-up, the only salamander farm we saw was deserted, with overgrown or empty outdoor tanks.

Reading about what is known about giant salamanders I am struck by the need for more basic biology, particularly their reproductive biology. A major research facility, aimed at multigenerational captive breeding, could, alongside further studies in the wild, well be justified. If the Giant Panda deserved such a major effort, surely the Giant Salamander does as well. Given the massive increase in internal tourism in China, a well-designed centre with stunning exhibits could be a major attraction and a useful source of income.

I can only hope that the conservation measures being supported by ZSL and partners in China are successful and the survival of the giant salamanders in the wild and throughout their range can be assured.


References are in previous post.

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