As a former tarantula keeper it is one of the most exciting moments to find a tarantula in its natural habitat. In this case we found dozens of them all close together in Singapore.
The approx. 1000 known species in the family Theraphosidae have a wide variety of appearances, from incredibly huge and heavy, to amazing patterns and vibrant colors. Even shapes differ, e.g. are there tarantulas with a horn or with gigantic back legs.
P. inermis though is a tiny tarantula with more standard appearance. The color is a pale brown with no popping highlights.
It has been described as Ischnocolus inermis 150 years ago by Ausserer (1871), and was transferred to Phlogiellus by Simon in 1903. For 118 years it is known as Phlogiellus inermis. Here’s an article on the relationship to other tarantulas.
The 150’s birthday of this Singaporean tarantula is our story. It shows how difficult etymologist work is.
Other tarantulas experience many more changes in their systematics, e.g. the Tliltocatl vagans, that has its third genus already. From the earlier linked article about Phlogiellus we have some prominent arachnologist mentioned, Pocock, Ausserer, Simon, Strand, Thorell, Raven, Schmidt, and the authors Nunn, West and von Wirth. All trying to bring a system to some small, orange, brown, grey or black tarantulas from Asia.
The question is always, which differences in features (shape of sexual organs, surface of the legs, spines, and many more) are valid to put some tarantulas in the same, or different genera. The fact that work has been done so many years ago does not help, because the code says once a species got a name, it stays with that name. The genus may change, but not the species name (epithet). Also the first publisher will always be mentioned, e.g. for our species it would be called Phlogiellus inermis (Ausserer 1871). The name is in brackets because he described it in another genus and it got transferred. If you describe a new species, you must make sure it has not been described before. If you would describe a well known tarantula like Brachypelma emilia now, all experts would say that’s not possible because it is obviously B. emilia. But if you find a tiny brown tarantula on a small Island in Indonesia for example, it is much more difficult to prove if it has been described before.
For further studies, some specimen of the described species will be preserved and usually placed in a museum, where other etymologist have access to it. Means you must find and examine such specimens when you describe or re-describe a species. Sometimes the spider might be lost, or mislabeled, or it has only been one gender described, and you don’t know how the other gender would look like. Or both are described, but it turns out that they are two different species. Of course the colors have faded and the body falls easily apart after decades in alcohol. Such collections can also contain spiders we never have seen in real, sometimes of massive size.
Our spider has 26 sister species in its genus, described and re-described from approx. 30 different etymologist. The genus has been established in 1897, but has been described again under the name Neochilobrachys in 1909, and 1920 again as Yamia, and one more time in 1995 as Baccallbrapo. Because all these names describe the same genus, they are not valid anymore. Aside from those genera, some Phlogiellus-species have been called Ischnocholus, some Selenocosmia in-between. These genera are valid, just some species didn’t belong there. Three other species have been in Phlogiellus for a while, but now are moved to three different genera. Chances are high that there will be many more revisions in future. You see, it is somehow remarkable, that Phlogiellus inermis is Phlogiellus inermis for 118 years already.
I wonder what Ausserer and co would have answered, if you asked them how they think systematics are going in 2021. And what it will be like in another 150 years.
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