A Kazakhstani Photographer Posts the First Known Photos of a Jumping Spider Species - Observation of the Week, 10/13/19

Our Observation of the Week is this Pseudomogrus dalaensis jumping spider, seen in Kazakhstan by @talgar-t64! These are the first known photos of a living individual of this species.

“People usually do not pay attention to what's under their feet. And there's this whole world,” says Anatoly Ozernoy. “And I want to show [these worlds] to people. Show their beauty, their physical perfection, their world. We should not destroy them, they have the same right to live on this earth. Earth is for everybody, it's not only for people.”

Anatoly lives in southeastern Kazakhstan, at the foot of the Ile Alatau mountains, and he tells me “a great variety of natural habitats is represented here: mountain peaks with glaciers, alpine meadows, old-growth conifer forest zones, steppe by the foothills and deserts further away from the mountains. This allows me to experience tremendous diversity of life without a need to travel long distances - everything's a stone's throw away.”

As a spider enthusiast, Anatoly has taken it upon himself to photograph local spiders, many of which are not well documented. “There are lots of endemic species here,” he explains, “but their scientific descriptions lack photos [and] most of them have never been photographed alive...So my photos are often the first ones of the species - this also adds quite a motivation to my research. I'm eager to find more of them, take pictures and share with people.”

One of those spiders is the one shown above, the jumping spider Pseudomogrus dalaensis. Anatoly tells me it’s known only from three locations in Kazakhstan “and out of the blue I found it just 13 kilometers away from one of those places in the fall, although I was betting on spring or summer. It was a great luck! The spider is small and I was fortunate enough to spot it on a large prickly shrub.”

With over 6,000 species, the Salticidae, or jumping spiders, are the most diverse of any spider family, and are pretty amazing. Perhaps the most visually-acute spiders, salticids have large, forward-facing eyes that allow them to find prey and judge jumping distances. This distance judging is accomplished not through binocular vision like we humans use, but “by comparing a blurry version of an image with a clear one, a method called image defocus.” And unlike, say, orb weaver spiders, male jumping spiders use visual cues when courting a mate; most famously those in the genus Maratus. Check out this video of a male courting a female!

Anatoly (above) says that iNaturalist has “proved very useful” when it comes to “photographing spider species, researching their distribution throughout the country, sharing local biodiversity with the community.

It's got various taxa distribution features, great tools for working with maps, plus every interested person has an opportunity to see observations. Moreover, I have an opportunity now to help others with identification of their spider observations and see for myself and learn new species and their habitats.

A huge thank you to @kastani for translating messages between myself and Anatoly, and to @zygy for bringing my attention to this observation. The generosity and passion of the iNat community is always humbling.

- Using laser vibrometers, researchers at UC Berkeley study the acoustic signals male jumping spiders create during courtship, which complement their visual dance. 

- Here’s a video of those sounds. 

Posted on October 13, 2019 04:46 PM by tiwane