Welcome

Welcome to my blog

This is where I post various musings about wildlife and ecology, observations of interesting species (often invertebrates)
and bits of research that grab my attention. As well as blogging, I undertake professional ecological & wildlife surveys
covering invertebrates, plants, birds, reptiles, amphibians and some mammals, plus habitat assessment and management
advice
. I don't work on planning applications/for developers. The pages on the right will tell you more about my work,
main interests and key projects, and you can follow my academic work here.

Thursday, 4 February 2016

Headlights and zebra stripes



Zebra spiders in the genus Salticus are a familiar sight in and around houses and other buildings in Britain and other parts of northern Europe, and their common name derives from their striped pattern.

Salticus scenicus, a common species near buildings.
As for other spiders in the family Salticidae ('jumping spiders'), the carapace ('head') is more-or-less squared off at the front with two large central eyes facing forward and two smaller ones at the corners (red lines in the image below). These are highly mobile with highly developed focusing mechanisms, and are able to see both colour and polarised light.  Just behind these are two tiny side-facing eyes (green lines) and then two more small, but easier to see ones (blue lines); these smaller eyes mainly detect movement and the spider is likely to turn quickly towards a moving object to focus to larger eyes on it.

Eyes of S. scenicus
This arrangement gives good forward binocular vision, unsurprising as they hunt by leaping at prey rather than by using a web. Instead, they attach an anchor-line of silk to the surface it is on, then the rear two pairs of legs are drawn in before being rapidly extended by pumping body fluid into them. In side view, the importance of frontal vision is clear as the carapace is extended forwards to form a short rostrum protruding above the legs.

On the hunt: S. scenicus emerging from a hole in a 'bug hotel'. The large front-facing eyes can be clearly seen.
Although S. scenicus is the commonest species to be found near buildings, there are other species in this genus and it is worth checking for them. They can be separated looking at the epigyne (in females) or the palps (in males). The clear presence of a large palp used in reproduction shows this is a male and its shape (circled below) is typical of S. scenicus.

Male S. scenicus showing the shape of the palp.
Though fairly small (this one is 5-6mm long, excluding legs), 'jumping spiders' are highly active in warm conditions, and therefore often seen - they are worth looking out for and even if you are not a spider-fan, they can be highly charismatic little creatures.

8 comments:

  1. Fascinating post. Thank you so much for sharing.

    ReplyDelete
  2. If you have never met an Eclectus I must warn you that it only takes a moment for these birds to steal your heart away. They can make you laugh, make your heart melt, and at times make you want to bite nails because they can be terribly hard-headed little critters. For more information visit https://electrus.company.com/
    parrot eclectus for sale

    eclectus parrot for sale

    parrot eclectus price

    eclectus parrot price

    eclectus parrots breeders

    eclectus parrot male

    eclectus breeders

    eclectus prices

    eclectus parrot cost

    ReplyDelete
  3. On the off chance that you have never met an Eclectus I should caution you that it just pauses for a minute for these winged creatures to win your love away. They can make you snicker, make your heart liquefy, and on occasion make you need to nibble nails since they can be horrendously determined little critters. For more data visit https://electrus.company.com/
    vosmaeri eclectus parrot

    solomon eclectus for sale

    red-sided eclectus parrot for sale

    buy eclectus parrot

    green eclectus for sale

    adult eclectus parrot for sale

    eclectus vosmaeri breeders

    Solomon island eclectus breeders

    vosmaeri eclectus parrot for sale

    ReplyDelete
  4. BIRDS FOR SALE


    Conures are very social, affectionate, and entertaining. They seek attention, and it is not uncommon to see them rolling on their backs to get your attention.
    Conures for sale


    Cockatoos Parrots are often described as intelligent and emotional birds. They are very popular pet birds with personalities as flashy and energetic as their crest.
    Cockatoos for sale


    Caique parrots are very intelligent and enjoy learning and showing off their tricks. However, they are very strong-willed and will need a firm hand in training and any interaction.
    Caiques for sale


    Amazons are brilliant and playful birds that love being the center of attention. They need lots of affection and time with their owners.
    Amazon Parrots for Sale


    African Grey's are most famously known for their high intelligence and fantastic talking ability. but they are so much more.
    African Grey Parrots for Sale

    Macaws are beautiful birds with large beaks, bright feathers, long tails, and white facial patches.
    Macaws for sale

    ReplyDelete
  5. Marvellous content and really thrilled to read your blog every time. Quiet good writing and easy to understand the facts well projected. Do you have any old cars still being dumped in our backyard well it's time to give it to us we would buy the scrap cars with the best offers.

    ReplyDelete
  6. Wao! The amazing and valuable blog I just love it. you need money well get money for used car and benefits you can find benefits about your used car and make money of them.

    ReplyDelete