Arachnology - Tumblr Posts
References:
Dunlop, J. A., Anderson, L. I., Kerp, H., & Hass, H. (2003). Preserved organs of Devonian harvestmen. Nature, 425(6961), 916–916. https://doi.org/10.1038/425916a
Machado, G., & Raimundo, R. L. G. (2001). Parental investment and the evolution of subsocial behaviour in harvestmen (Arachnida Opiliones). Ethology Ecology & Evolution, 13(2), 133–150. https://doi.org/10.1080/08927014.2001.9522780
Martens, J. (1993). Further cases of paternal care in Opiliones (Arachnida). Tropical Zoology, 6(1), 97–107. https://doi.org/10.1080/03946975.1993.10539212
Mora, G. (1990). Paternal care in a neotropical harvestman, Zygopachylus albomarginis (Arachnida, Opiliones: Gonyleptidae). Animal Behaviour, 39, 582-593.
Nazareth, T. M., & Machado, G. (2009). Reproductive behavior of Chavesincola inexpectabilis (Opiliones, Gonyleptidae) with description of a new and independently evolved case of paternal care in harvestmen. Journal of Arachnology, 37(2), 127–134. https://doi.org/10.1636/ST08-32.1
Shear, W. (2009). Harvestmen: Opiliones—Which include daddy-long-legs—Are as exotic as they are familiar. American Scientist, 97(6), 468-475.
A couple of tags on my previous comic about Opiliones were talking about other daddy longlegs - that’s the trouble with common names!
(Deleting and reposting because I realized I uploaded it wrong - sorry to anyone who commented, I’m still getting used to Tumblr again and very much enjoying it!)
Vida's Sheep Jumping Spider: researchers believe that these tiny spiders developed their "woolly" appearance as a way to mimic lacewing larvae or scale insects
The scientific name for this species is Oviballus vidae, but it has also been referred to as the "sheepy jumping spider" or "Vida's jumping spider." It was discovered in 2015, and first described (in a formal context) back in 2020.
As this article (PDF) describes:
Recently, two new salticids, R. legitima and Oviballus vidae were described from South Africa, and suggested to be mimics of either scale insects (Hemiptera: Coccoidea) or lacewing larvae (Neuroptera: Chrysopidae), due to their white colouration and the presence of peculiar tufts of white setae on the body.
The possibility of [scale insects] being the model is supported by Oviballus vidae being regularly collected from plants with woolly scales, although the movements of O. vidae quite closely resemble those of chrysopid larvae.
In fact, a fourth species of possible scale mimic, a new Rhene species, was recently discovered in a collection of salticids from southern Mozambique, indicating that this phenomenon may be more widespread than has previously been known or even suspected.
O. vidae was named after Vida van der Walt, the photographer who captured some of the first images of these spiders back in 2015, just after the species was discovered by Dr. Galina Azarkina. Vida van der Walt also took the photographs that appear in this post.
Sources & More Info:
Arthropoda Selecta (scientific journal): Rediscovery and Redescription of Rhene cooperi, another possible mimic of scale insects (PDF)
Spider Club of South Africa: Two New Species Named After SA Photographer (PDF, with the relevant info on page 5)
Field Guide to the Spiders of South Africa: Section on Vida's Sheep Jumping Spider
Rainbow Jumping Spider (Chrysilla volupe): these colorful spiders were regarded as an extinct species for nearly 150 years, until they were finally rediscovered in 2018
The males of this species have a stunning, almost rainbow-like appearance, thanks to the bands of color and iridescent scales that cover their bodies.
Despite the fact that Chrysilla volupe is probably the most flamboyant spider in the world, it was still lost to science for nearly 150 years. The species was first described in 1879, but there were no documented sightings of it for 139 years after that, until researchers finally tracked it down again in 2018. The female of this species was also described for the very first time in 2018 -- prior to that, Chrysilla volupe was known only from male specimens.
The spiders have been found in certain parts of India, Sri Lanka, Nepal, and Bhutan. Like most jumping spiders, they are quite small: the males can measure up to 5.44mm long (and that includes their outstretched legs), while the females are less than half that size.
Sources & More Info:
Journal of Entomology & Zoology Studies: Chrysilla volupe Spider Spotted in Eastern Ghats, India (PDF)
The Hindu: Rare Chrysilla volupe Spiders Discovered at Puttenahalli Lake
Arthropoda Selecta: First Description of the Female of Chrysilla volupe from India, with Notes on the Species' Distribution & Life History
Peckhamia: New Records of Jumping Spiders from Nepal
Global Biodiversity Information Facility: C. volupe
Latrodectus mactans, the Black Widow.
Steatoda grossa, The False Widow