Stretch spider portrait

I found this female stretch spider, Tetragnatha, in the garden this evening. I remembered that they have lovely faces and I gave it a try on the white bowl aiming for a frontal shot. They have their eyes in two rows, the bottom central pair facing forward. The face shot also allows to see its enormous fangs. After a short session in the bowl, I returned the spider to her leaf and she rapidly climbed to her retreat.

The resting position of Tetragnatha on a leaf.

Two common ground beetles

We came across two Ground Beetles, and they happen to be two of the commonest species in the UK. The top shot is the Strawberry Seed Beetle, Harpalus rufipes, a female. The elytra of this species look duller than the thorax, as they are covered with fine hairs, which you can see glowing in the photo below of the same individual, as they glistened with the flash light. They eat many vegetable matter, and appear to be partial to ripe strawberries.

The next species, larger (15-20 mm), is the Black Clock beetle, Pterostichus madidus, a very shiny, large headed species with impressive jaws and eyes. They are mainly predatory, and feed on ground invertebrates. This individual is a male, recognised by the enlarged tarsi of the forelegs.

There are many species of ground beetles (about 370) and many are hard to identify. These are some websites that might help you ID them:

Mark Telfer's website

Mike's Insect keys

Ground beetles of Ireland

Watford Coleoptera Group

Let me know if you know any others!

First queen wasp

The first queen wasp of the year got herself trapped in the conservatory. She was cold and calm, so I decided to give her a session with the white bowl. I held her in a tissue and placed her onto the bowl and she posed nicely. After a few photos, with me breathing onto her, she warmed up, started grooming her antennae and flew onto the window, and I let her go.
 The only overwintering stage of social wasps are queens. Males died at the end of the autumn after mating, and the workers a bit earlier. Their large paper nests are now empty, as the life cycle of social wasps lasts for less than one year. Queens overwinter in buildings or other dry places, but the strong wind and mild temperatures have probably helped stir this one out of her hiding place.
 The 'anchor mark' on her face identifies her as a common wasp, Vespula vulgaris.

Side view showing how hairy she is.

And a little grooming of antennae before flying off.

Spider portraiture

It is quite flattering that several people have congratulated me over the years on the invertebrate photos I feature in BugBlog, thank you guys! I don't claim to be a photographer, but I am happy to share a few tips on the white bowl technique, which I regularly use on critters found around the house and garden, especially on non-flying ones. As today I found the first male house spider, Tegenaria sp., of the season, I thought a post on this topic was timely.
Before my daughter finished saying 'spider!' I got the little beast running across the kitchen floor into a little plastic pot. For this, I save any little plastic pot I come across. You know the onion salad pot from an indian takeaway? ideal! To hold the bug for a few minutes the pot does not even need to have holes on the top. I also have a 'proper' bug viewing pot (like the one featured in the photos below). My bug pots are always available on the side of the kitchen and I always carry one in my bag.
The second piece of equipment is the bowl. A flat-bottomed white bowl, like those used for soup, is ideal, as its sides help reflect the light. Better if there is a smooth transition from the bottom to the sides, as it will reduce undesirable reflections.
 I take the bug pot and bowl to the conservatory (or outside, weather permitting), as I like as much natural light as possible.

And push the cat out of the chair (sorry!).

 Then I remove the lid of the bug pot, put the bowl on top, turn it round to transfer the spider to the bowl surface.

I'd like to say that, although it is a common technique, I don't like to use the fridge to cool down the animal, I am impatient and I want to get the photos and release the animal as soon as possible. Many of the bugs are naturally slow and settle quickly on the pot, or stop long enough for the shots. Male spiders at this time of the year are challenging, as they are very jittery and require a bit of attention until they are posing well. Usually, tapping on the table will startle them and they will stop running around. Unfortunately, they often stop leaning on the side of the pot, so when you remove it, they are settled in awkwardly like so...

...which is not ideal. I move the pot slowly until the spider is in the middle and blow softly under the pot, until the spider spread its legs.

Now lets go to camera settings. I don't own a DSLR, just a bridge camera (Canon Powershot G12, if you are wondering), but you can achieve a similar effect with any portable camera. I first set the flash on, and increase the flash setting to +2, this is important if the bug is dark, as the auto flash setting will result on an overall dark animal and not a very white background. You might need to experiment with your camera to find the best flash setting.

No flash

Flash on to +1

Then I set the focal point to the top left hand side of the visual field (nearer to the flash itself), instead of the central position. This ensures the animal is not in the shade of the objective. If I didn't do this, once I cropped the photo, the bottom right corner would be grey, not white, as it would be shaded by the objective. You can simulate this on a cameral without this setting by focusing in the middle point and then moving the camera trying not to lose the focus so that the animal is located in the top left hand side of the visual field.
 Today, I experimented by holding the camera vertical, so that the flash light came exactly in front of the spider.
Set the camera to macro, and fire away. I usually take lots of photos, as I want to get the focus right on the animal's eyes and I try also several angles, which are often useful for ID purposes.
  I download the photos in the computer and do some basic processing. Crop the white/grey space out, adjust the levels so that the white background is actually white, remove specks of dust or dirt and sharpen a little. That's it!

Cropping

White level adjustment

 This one is my favourite of the session today. Although the white background is not perfect, as it is greyer on the right hand side, I like the spooky effect of the spider leg shadows.

Cock-tail beetle

We found this rove beetle, Ocypus sp. (possibly nitens) running across the garden patio. It lifted its tail briefly a couple of times, honouring one of its common names 'cock-tail beetle', but afterwards it decided to groom itself at the bottom of the white bowl. These are usually nocturnal and predatory, often found under stones and logs during the day. They are quite fast and usually hide before photos can be taken in their natural habitat.

UPDATE Fauna, from Wild about Britain, suggested that this is Tasgius (which used to be Ocypus). I am thinking T. ater, as it has a very shiny head. The enlarged tarsi makes it likely to be a male.

A leggy centipede

I was pleased to come across this centipede Stigmatogaster subterranea in leaf litter while gardening.  I counted 79 leg segments - with a pair of legs each -, a normal number for this species, which can easily be the leggiest beast in the garden. Winter has been very long this year: no bees or butterflies, or even droneflies, and very few active invertebrates around, so BugBlog remains dormant, but hopefully not for long.

Daddy superlong legs

Today's post celebrates harvestman season. This one, a male Leiobunum rotundum, sat on an outside wall, all outstretched legs. With an enormous leg span, well over 10 cm, it is amongst the longest legged harvestman in the UK. The species can be recognised by its dark mask around the eyes and contrasting black legs. Males have a rounded orange body, while females are brown-grey with a broad dark stripe along her back. The next photo gives you a idea of the relative size of the legs in proportion to the body.

Garden Snail Parade

Since I started this blog, I have been surprised by the diversity of land snails about in the city. As I have managed to get most of them on white background, I decided to write a post and display them all together.

Moss snail, Lauria cylindracea, a tiny, easily overlooked species which gives birth to live offspring. 

Garden Snails, Helix aspersa (=Cantareus aspersus), unashamedly mate in the middle of your garden  path throwing darts at each other. 

Girdled Snails, Hygromia cinctella, like walls. An introduced species since 1950, still expanding across Europe from the Mediterranean.

Kentish snail, Monacha cantiana prefers drier places. This species, introduced in the UK during Roman times, is a very common snail in my local Wildlife Garden. They can be darker with pale speckling.

Glass Snails, Oxychilus draparnaudi, are carnivorous snails that have caused havoc on native snails when introduced outside the UK.

Amber Snails, Succinea putris usually live in very damp places, but can be also found away from water. They cannot completely retract their bodies inside their shells.

Brown Lipped Snails, Cepaea nemoralis are very polymorphic in colour and pattern.You might be lucky to have these beauties in the garden.  

Have you noticed all the snails are facing to the right? This is because most (90%) of all snail species have right-handed shells (dextral). Occasionally a left-handed individuals appear in populations of right handed snails. These face a problem when trying to mate, as the genital opening will face away from most other snails in the population. The genetics of shell handedness has been elucidated in some species and appears to be determined by mutations in a single gene, but the left-handedness trait is expressed not in the mutant, but in the resulting offspring.

More information

Visit the Molluscs posts in Bugblog.

Terrestrial Mollusc Tool. A wonderful resource for US molluscs. Contains also lots of info on introduced European slugs and snails.

Male garden spiders out on a mission

Even my four year old has noticed that there are lots of spiders about. She found many fresh webs by Araneus diadematus today, and she asked why are there so many now. I tried to explain that they have grown large recently, and that's why we are seeing them more easily, but she discarded this and came up with her own explanation: is her watering the plants yesterday what must have made them grow. Female Araneus diadematus are reaching quite large sizes now, although there is a lot of size variation. The record holder in our garden sits by two rubbish bins, and has probably been gorging on the flies the rubbish attracts. Males have also reached adulthood and, in contrast to the sit-and-wait females, are moving between bushes in search of receptive females. I have come across three in the last few days. They have slimmer abdomens and robust legs and their palps are quite noticeable. The male must be careful, though, as females will quickly make a meal of him if he does not reach their high standards. I found this male getting closer to a small female's web. As he was on a broom, focusing him was very tricky and I resorted to trying the white bowl.

Inside curly cherry leaves with their food

Yesterday we gave our cherry tree a light trim, removing shoot tips damaged by the black cherry aphid. The leaves curl up, sheltering hundreds of aphids (above). Inside the leaves, with their prey, there were hundreds of Harlequin larvae larvae, a few 2 spot larvae and with few adults of both species, a 10 spot ladybird and a few predatory hemipteran bugs.

A mirid bug Deraeocoris ruber (I think!)

10 spot ladybird, near a black cherry aphid

Fully grown Harlequin larvae

2 spot ladybird larvae

Two spot ladybird

An unusual 2 spot ladybird with 3 spots!

A Strawberry Seed Beetle

Given that the weather is so damp and cold I am seeing very few insects these days other than bumblebees. At least I have plenty of time to tidy up my ever growing photo library! While going through my ground beetle photos, I thought I would share this shot of  Harpalus rufipes, a common species that I have even found inside the house. The species is quite distinctive with its orange legs and its wings covered on very fine hairs - giving the elythra a matt feel when compared with head and front of the thorax. This is an omnivorous beetle: it will predate small invertebrates but also feeds on seeds, and gets its English name from the damage it inflicts on strawberries. The species is biennial. It breeds in August and the adults overwinter and overlap with the larvae. The larvae dig deep vertical where they cache seeds, which I thought it is pretty cool behaviour for a beetle. As other common European invertebrates, it was introduced in North America before 1937.

More information

Loughridge, A., & Luff, M. (1983). Aphid Predation by Harpalus rufipes (Degeer) (Coleoptera: Carabidae) in the Laboratory and Field. The Journal of Applied Ecology, 20 (2) DOI: 10.2307/2403519


Hartke, A., Drummond, F., & Liebman, M. (1998). Seed Feeding, Seed Caching, and Burrowing Behaviors of Harpalus rufipes De Geer Larvae (Coleoptera: Carabidae) in the Maine Potato Agroecosystem. Biological Control, 13 (2), 91-100 DOI: 10.1006/bcon.1998.0645

Never hold a Black Clock in your mouth

I found a squished ground beetle on the pavement today, Pterostichus madidus, and I thought I would share with you some photos from last year of a very alive individual of this species . Curiously this carabid beetle has a curious English common name: the Black Clock. According to the book Bugs Britannica, by Marren and Mabey 'clock' was a word in widespread use to mean any big buzzing insect. As many carabids, however, this is a fast, non-flying nocturnal predatory beetle which runs to hide quickly when uncovered. This one was found under a grass tussock in the garden. Look at his sharp jaws!
 Ground beetles have glands at the end of the abdomen that produce defensive, foul tasting and caustic secretions. I must quote here an incident involving ground beetles described by Charles Darwin

I must tell you what happened to me on the banks of the Cam in my early entomological days; under a piece of bark I found two carabi (I forget which) & caught one in each hand, when lo & behold I saw a sacred Panagæus crux major; I could not bear to give up either of my Carabi, & to lose Panagæus was out of the question, so that in despair I gently seized one of the carabi between my teeth, when to my unspeakable disgust & pain the little inconsiderate beast squirted his acid down my throat & I lost both Carabi & Panagæus!

The pains beetle collectors went through to capture priced ground beetles! You can admire the handsome Crucifix Ground Beetle (Panagaeus cruxmajor), also known as 'Darwin's lost beetle' here. Unfortunately, due to collecting and habitat degradation, this species, formerly widespread, is now just know from three populations in the UK.
But back to my beetle, I managed to take some shots of the individual scurrying off for cover on the soil, and then I decided to capture it and give it a session in the white bowl. I think the following two photos show the pros and cons of the natural versus the white background.

Pterostichus madidus, 12 May 2012

More information

Charles Darwin letter to Leonard Jenyns in the Darwin Correspondence project.

Crucifix ground beetle (Panagaeus cruxmajor) UKBAP plan.

The Panther Spider

Upon removing a pot from a wall this morning, I exposed a beautiful adult female Mouse Spider,  Scotophaeus blackwalli, her abdomen full and glistening. Although initially flighty, she eventually settled on the white bowl and allowed me to take her portrait. In his classic book 'The World of Spiders', packed full of interesting observations on the behaviour and natural history of British Spiders, W.S. Bristowe described these nocturnal spiders and their relatives as the 'panthers or pumas of the invertebrate world'. However, a few lines later he pushed aside their hunting habits and instead gave this spider a much less impressive common name:

If an English name were needed for our only domestic species, which is found rarely away from man's buildings in hollow trees, it would be appropriate to call her the Mouse Spider on account of her glossy grey abdomen. But she can be a very fierce mouse. She reaches 11 mm. and has short brown legs and a rather narrow head.

He goes on to describe its ability to subsist without water for months and its prowling behaviour 'at night on walls and ceilings in search of prey, retiring behind pictures or onto crevices in walls during the hours of daylight.' He must have kept this spider in captivity and observed it carefully and he goes on to describe its encounters with prey and its short mating behaviour. He describes to have observed two cases of mating in July. And it is at this time of year that adult specimens can commonly be found.

More information
Bristowe, W.S. 1958 The World of Spiders. Collins New Naturalist Series, London. 304 pp.

Crane Fly halteres

This Crane Fly or Daddy Long Legs (possibly Tipula scripta) got into the house and I gave a try to getting its portrait on a white background. It is pleasantly surprising how many insects that I expect to fly away immediately do actually stay still through my white bowl session. The little knobbed structures sticking out at the sides of the body are the halteres, typical of all flies but more prominent in these large flies. They evolved from the hindwings and when in flight move in opposite directions as the wings and are involved in balancing and steering and contribute to the exquisite flying abilities in the group, although crane flies themselves are weak, wobbly fliers

The Footballer hoverfly

From mid April up to October, you might come across this handsome hoverfly resting on leaves or feeding on flowers either close or away from water. This species is Helophilus pendulus, the commonest of its genus in the UK, distinguished by other species by the parallel yellow stripes in the thorax, black stripe on its face and the mainly yellow hind tibia. The genus Helophilus, which is a wasp mimic, is closely related to Eristalis, the droneflies, which are bee mimics. Both genera share a rat-tailed aquatic or semiaquatic larvae. I found this female sitting on a sage leaf after a light shower. She was cold and reluctant to fly, and with a bit of coaching, she climbed on the white bowl and let me take her portrait.