The October Spider of the Month (SOTM) is this green comb-footed spider (Theridiidae), photographed by Kyle Thomas in Magoebaskloof, Limpopo. We are not sure of the genus, but it’s almost certainly an undescribed species. Regarding this find, Kyle said the following:
“Wherever I visit this forest in Magoebaskloof, I always think it will be my last time and push myself to explore further and make the most of it. There have been quite a few undescribed species I have come across here and didn’t think I could find more, but was yet again surprised and it produced a few more unknowns, among them this green jellybean of a Theridiidae. These appear to have a preference and only made their retreats on the underside of White Ironwood leaves. I assume this is because the shrub is evergreen and does not shed its leaves easily. I am still struggling to place this in a genus and have considered genera such as Exalbidion, Theridion and Chrysso, but of course cannot be certain of this. We can hope that one day it is described.”
There is quite a variety of green spiders that have a translucent, jelly-like appearance. Most are in the family Theridiidae (Kyle has photographed a few of them); others include the Synotaxidae (previously in Theridiidae), the green grass crab spiders (Oxytate spp.; Thomisidae), green jumping spiders (Asemonea spp.; Salticidae), etc. This translucent appearance in some green spiders probably comes from a thin cuticle or a lack of pigment. Perhaps this helps them to camouflage themselves on vegetation.
I can’t really say much about this specific spider, as we’re not really sure what it is, so I’ll just say something about the family.
The Theridiidae (the well-known button/widow spiders belong to this family) are commonly called comb-footed spiders, due to the stiff “comb” of hairs on the tarsi of their hind legs, which cannot be seen with the naked eye. They are also called cobweb or tangle-web spiders, due to their irregular three-dimensional webs. Not all theridiids spin webs, though.
The Theridiidae family is a very big and highly diverse family, consisting of 140 known genera, with 2634 described species. There are, however, MANY undescribed species, especially here in South Africa, where taxonomists willing to work on this family are scarce.
The family name Theridiidae basically means “little beasts”, derived from the Greek name (thēridion) for the type genus, Theridion, which means “little wild animal”, “little beast”, or “small wild creature”. It is a diminutive of thērion, meaning “wild animal” or “beast.”
Out of 178 people who voted, Kyle’s photo received 116 (65%) votes. This is Kyle’s fifth SOTM. He has also won a Spider of the Year (SOTY) once. Congratulations, Kyle, and thanks to everyone who voted!