Rhomphaea: ridiculously long theridiids

Male Rhomphaea fictilium – a theridiid with a ridiculously long abdomen and pedipalps! Photo: Al Denesbeck (used with permission). I’ve written about long spiders before: the “stretch spiders” in the family Tetragnathidae (long-jawed orb-weavers) are notable for their elongated bodies as well as their long jaws. When I first spotted Rhomphaea, I thought it might be a tetragnathid, before taking a closer look and realizing it must be something else entirely. As it turns out, Rhomphaea…

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Oecobiidae

Last week one of my undergraduate labmates found a tiny “free-range” spider running along the wall of one of the basement rearing rooms where we keep our black widows at UTSC. We regularly find common house-dwelling spiders (most often false widows, Steatoda grossa) in the rearing facility because we also keep a large supply of fruit flies and crickets to use as spider food, some of which inevitably escape and thus make it a prey-rich…

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A quick survey

Dear readers, I’ve teamed up with Science Borealis, Dr. Paige Jarreau from Louisiana State University and 20 other Canadian science bloggers, to conduct a broad survey of Canadian science blog readers. Together we are trying to find out who reads science blogs in Canada, where they come from, whether Canadian-specific content is important to them and where they go for trustworthy, accurate science news and information. Your feedback will also help me learn more about…

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Myrmecophilic spiders

Note: All photos in this post are copyright Sean McCann. Yesterday, for the final day of Arachtober, Sean and I went to Tommy Thompson park in Toronto to look for some autumn arachnids and other arthropods. Sean was very excited when he turned over a rock and found a nest of acrobat ants, Crematogaster cerasi. The genus Crematogaster is mainly tropical, and we didn’t have them back in BC, so it was a pretty cool find for us. Then we took…

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Pirate spiders

Mimetidae are the pirates of the spider world, but their acts of theivery take place on the webs, rather than ships, of other spiders. The name Mimetidae means “imitator” and is thus a very fitting name for these sneaky spiders. A mimetid found at Payne’s Prairie in Florida. Photo: Sean McCann (used with permission). Common names for this family include pirate spiders and cannibal spiders, for reasons that will soon become clear. They have a worldwide distribution,…

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Opportunity makes a thief

Sometimes unexpected things happen when you’re observing spiders. The following series of photos is by Catherine Aitken, who has a wonderful wildlife photography blog: Lardeau Valley Time. She recently witnessed and captured this incredible interaction in her garden, and kindly gave me permission to share her photos here. Here we see a lovely pink and white flower crab spider (Misumena vatia) peacefully slurping her lunch (an unfortunate hoverfly). Photo: Catherine Aitken (used with permission). But soon…

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Castianeira: ant-like spiders

The spider genus Castianeira (in the family Corinnidae) is one of my favourites. These small spiders are rather elusive, but so beautiful! There are currently 128 known species in the genus, so I will only be able to highlight a small number in this post. This should nonetheless provide a glimpse into the diversity of gorgeous forms they take! Castianeira dorsata from Arizona. Photo: Sean McCann Natural History Common names for the family Corinnidae include “ground sac spiders” (they used to be included in the…

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Segestriidae: tube web spiders

Recently Sean and I took a quick trip down to Bellingham, Washington, to meet up with a friend. While we were wandering around a beachfront park, we encountered this beautiful spider under the loose bark of a tree. I didn’t recognize it, and we didn’t have our field guide with us, so it wasn’t until we got home that we were able to identify it as Segestria pacifica – a member of the tube web spider family…

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Web reduction for rival obstruction!

This post is about a new paper just published online in the journal Animal Behaviour, titled “Web reduction by courting male black widows renders pheromone-emitting females’ webs less attractive to rival males” by Catherine Scott, Devin Kirk, Sean McCann, and Gerhard Gries! You can read the full text here (free access until 28 August, 2015).           All photos and video are copyright Sean McCann.  This short video shows a male western black…

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A tiny tarantula

This is another post about spiders that Sean McCann found and photographed on his recent trip to Guyana.  When you think of tarantulas (mygalomorph spiders in the family Theraphosidae), the first thing that comes to mind is probably a huge hairy spider like the famous face-sized Goliath bird-eating spider. Sean with a male goliath bird eating spider on his head in Guyana. Note: don’t try this at home. Photo: Jonathan Meiburg. But not all tarantulas are large! Here is…

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