Tag: Slugs & Snails
Turned to Gold
x4 images. Double click to enlarge in full.

I don’t tend to post many slugs on this blog, although I have photographed quite a few, because I realise they are probably not everyones favourite animal. Yet I think this particular one with its gold speckling which are chromatophores (pigment cells) catches the eye and stand out amongst a world of slithering slugs.

It is called the Brown Soil Slug (Arion (Kobeltia) distinctus), and I often come across it in the garden.

The 2nd image down shows a slug mite Riccardoella (Proriccardoella) oudemansi crawling just below the mantle. Called the White Slug Mite, it is a parasite which infest the lungs of slugs and snails feeding on the hosts blood.

About Slugs And Snails
People maybe surprised to know that molluscs consist of the second largest group of animals on earth after the insects, with some 100,000 species plus. Of this group the gastropods are the largest of the mollusc group, with more than 50,000 species globally. They have been around for at least 500 million years. Their habitats can be marine, freshwater, estuarine, or terrestrial. Included in this class are the shell covered snails. limpets, sea hares, and the shell-less slugs.
The body of the snail consists of a large muscular foot, a visceral hump which is contained within an asymmetrically coiled shell (a univalve) a head with eyes and tentacles, and a mouth that contains a rasping tongue used to remove, crush and grind food. Most species of snail are herbivores, whilst others feed on live prey or carrion. They are mainly active at night so their bodies do not dry out in the sun, and during the day they hide in dark, damp places. Those with shells which not only give them some protection against predation, but also protection from desiccation, hide within them and seal themselves against rocks, stones, or vegetation.
Order: Stylommatophora (Air-breathing Terrestrial Slugs & Snails)
This taxon, now considered to be a clade, is a very large group of pulmonate (air-breathing) land snails and slugs. They are characterised by having two pairs of retractile tentacles with eyes located on the tips of the larger tentacles.
Order: Basommatophora (Freshwater Snails)
In this order are the air-breathing land snails which are found in ponds, ditches, streams, rivers and shallow lakes. They are characterised by having their eyes located at the base of their non-retractile tentacles, rather than at the tips, as in the true land snails in the order Stylommatophora. The majority of basommatophorans have shells that are thin, translucent, and which are fairly colourless.
Order: Neogastropoda (Whelks, Cones & Tritons)
These gastropods are mainly deposit feeders or predators. They all have a well-developed siphon for detecting prey. The larger bottom-dwelling carnivores commonly feed on bivalve molluscs, other gastropods, sea urchins, polychaete worms, and even fish. They will often burrow into the sand to reach their prey.
Order: Neotaenioglossa (New Gastropods)
This order of mollusc is believed to have evolved around 70 million years ago during the last days of the dinosaurs. They are characterised by the possession of only one gill, one auricle, one kidney and by siphon. This order is generally considered to be the most advanced of the prosobranch molluscs, which include the familiar whelks.
Tree Slug
Lehmannia marginata
A pale, translucent slug which is greyish-buff colour, and has a pair of dark lines running along its sides. Length 60 to 90mm.
It can be seen all year-long, and is found in on trees, usually in wet weather. It produces large amounts of watery mucous when disturbed as a defence measure. Common and widespread in woodland in W Britain and Ireland.
Photograph taken June 2015, rear garden, Staffordshire. © Pete Hillman 2015. Camera used Nikon D3200, with Sigma 105mm macro lens.
Chestnut Slug
Deroceras invadens
Also called the ‘Brown Field Slug’, this has a translucent grey-brown body, although it may be darker. The mantle is usually tinged chestnut, and it usually, but not always, has a pale ring around its respiratory pore. It has a very short keel. The mucus is colourless. Quite a fast-moving slug. Length 25 to 35mm.
This slug can be a significant pest in gardens, allotments and nurseries and will eat many types of plants and seedlings.
Found in woods, but especially parks and gardens. Discovered under logs, stones and paving. Introduced to Britain and Ireland in the early 1930s, and has spread rapidly since 1975 and has become common and widespread.
Photograph taken November 2012, rear garden, Staffordshire. Nikon Coolpix P500. © Pete Hillman 2012.
Netted Slug
Deroceras reticulatum
This slug just loves to eat the bird food I put out, apart from my plants. You can see some probable slug eggs just to the bottom right of its back end.
Also called the ‘Field Slug’ or ‘Grey Field Slug’, this is a fairly variable slug in colouration, but it usually has a pale cream body with a brownish mantle which has a netted appearance. It has a truncated keel. It produces clear mucus in large quantities, but it turns milky white when irritated. Similar to the Arctic Field Slug (Deroceras agreste). Length 35 to 50mm.
A very destructive slug and hated by gardeners for it eats the leaves of many various plants and crops, including seedlings. Found in various habitats including agricultural land, parks and gardens. Common and widespread throughout.
Photographs taken November 2012, rear garden, Staffordshire. Nikon Coolpix P500. © Pete Hillman 2012.
Leopard Slug
Limax maximus
Also called the ‘Great Grey Slug’ or the ‘Giant Garden Slug’, this is a large slug which is yellowish-grey to pinkish in colour, although this can be quite variable, with distinctive dark brown blotches and spots. It has a pronounced dorsal keel, and the sole is whitish. Its mucus is sticky and clear. Length 100 to 150mm.
It feeds on fresh and rotting plants of many kinds, and fungi.
Commonly associated with human habitation, and is found in gardens, cellars and outbuildings. It is also found in damp and shady hedgerows and woods. It hides during the day under logs and stones. Common and widespread.
Photograph taken November 2012, Warley Woods, Staffordshire. Camera Panasonic Lumix DMC-FZ38. © Pete Hillman 2012.
Green Cellar Slug
Limacus maculatus
Also called the ‘Irish Yellow Slug’, this is a medium-sized to large slug with a short keel. The body colour varies from pale ochre through to yellow-green to grey. The body has dark blotches or spots. The mucous is colourless. It has grey-blue tentacles. Similar to the Yellow Cellar Slug (Limacus flavus), which is a brighter yellow, has smaller spots and blotches, and has blue tentacles. Length 80 to 130mm.
It feeds on seedlings, vegetables, fungi, lichen, and decaying matter. It will even feed on pet food found indoors and old, damp wallpaper.
Commonly associated with gardens and houses, and it will venture indoors after dark. It prefers dark and moist habitats, and it may frequent cellars, greenhouses and sheds. Common and widespread throughout Britain and Ireland.
Photographs of Green Cellar Slug (Limacus maculatus), taken January 2014, front drive, Staffordshire. © Pete Hillman 2014. Camera used Nikon D3200, with Nikon 18-55mm lens.
Brown-lipped Snail
Cepaea nemoralis
Also known as the ‘Grove Snail’ or the ‘Banded Snail’, the lip of the shell is always dark brown. The shell colour is variable, from cream, yellow, brown or pink, and is often similar to the White-lipped Snail (Cepaea hortensis). Shell diameter 20 to 24mm.
Found in a range of habitats, but favours woodland, hedgerows, meadows and sand dunes. Also found in gardens. It feeds on a wide range of vegetation. Common and widespread throughout, except northern Scotland.
Photographs of Brown-lipped Snail (Cepaea nemoralis), taken October 2011, local field, Staffordshire. © Pete Hillman 2011. Camera used Panasonic Lumix DMC-FZ38.
Common Limpet
Patella vulgata
Have you ever wondered what the underside of a limpet looked like? Note the large muscular foot, the relatively small mouth above, and the tentacles either side.
The Common Limpet has an ashen-grey or greenish-blue shell, sometimes with a yellow tint, and with radiating ridges. It is conical with an almost central apex. The shell is often covered in barnacles. The sole of the foot is yellowish or orange-brownish with a green tinge. Shell length 6cm. They are fairly long-lived, up to 15 years.
It inhabits the intertidal zone, clinging tightly to rocks along the shore or in rock pools, and with its thick shell it is able to withstand the pounding ocean waves, exposure to drying out, and attacks from birds or fish. It grazes on algae growing on the rocks beneath the water. It is not ‘stuck’ in one position as it may always appear to be, but follows a mucous trail as it feeds and finds it way back. Scarring maybe evident on the substrate where it has ground it down to get the perfect fit. Common and widespread around the British coasts.
Photographs of Common Limpet (Patella vulgata), taken August 2011, Saundersfoot, Wales. © Pete Hillman 2011. Camera used Panasonic Lumix DMC-FZ38.
Common Periwinkle
Littorina littorea
Also called the ‘Edible Periwinkle’, the shell is variable in colour, from black and grey to brown, white or red, and usually patterned with spiral dark lines. It is conical in shape with a pointed apex. This is the largest British periwinkle, but is usually smaller than 50mm.
It favours rocky shores upper to lower zones with a good covering of seaweed. It can also be found in mud-flats or esturaries. The Common Periwinkle is a herbivore which grazes on seaweeds. Widespread and abundant throughout.
Photographs of Common Periwinkle (Littorina littorea) taken June 2012 (top 2 photos) and April 2014 (bottom photo), Llandudno, Wales. © Pete Hillman 2012 and 2014. Cameras used Panasonic Lumix DMC-FZ38 and Nikon D3200, with Sigma 105mm macro lens.
Well Worn But Ready For Autumn
American Slipper Limpet
Crepidula fornicata
This limpet has a humped, smooth shell with variegation in colour, usually pinkish, orangey, cream or purplish. It has a fairly thick shell with a shelf on the underside, which resembles a slipper. Shell length 5cm. Shell height 2.5cm.
It is found on the lower shore, attached to rocks and other shells, and they form stacks of up to ten individuals or more. They begin life as males, and then change progressively to become females. An introduced species from north-east America in 1887, the Slipper Limpet is quite an invasive species which competes with native oysters for space and food, and is also a threat to Common Mussel beds. Common and widespread.
Photographs of American Slipper Limpet (Crepidula fornicata), taken August 2012, Bournemouth, Dorset, . © Pete Hillman 2012. Camera used Nikon Coolpix P500.
Following The Storm
Pfeiffer’s Amber Snail Oxyloma elegans
Large Red Slug
Arion (Arion) rufus
I often see these in my garden after dark, or after heavy rain when they come out to feed or look for a mate. It can be one of those pests which just love to munch through your garden, but sometimes visiting frogs and toads help to keep them down. I noticed for the first time when I was photographing this particular individual how when he or she was bunched up to protect itself, it began rocking from side to side, which can be a characteristic of this species.
I find with this type of slimy creature, especially after rain, you have to be conscious of the light and how you use flash as you can get many blown highlights which does not always look nice. I used the natural light in most of these images, but of course a good flash diffuser could also be used if the area was shaded or the day overcast.
This medium-sized to very large slug is also called the ‘Great Red Slug’, ‘European Red Slug’, amongst other names. It has a differing range of colour forms, from yellow, orange, brown and rarely black. It has a striped fringe along the foot which is characteristically brighter than the body colour, usually bright orange or orange-red. The sole is often paler than the body sides. The tubercles are very course. The mucus is thick and sticky, and usually clear, although it may have an orange tinge. Length 60 to 140mm. Similar to the Large Black Slug (Arion (Arion) ater), which is the duller of the two species, with a darker foot fringe.
They feed on carrion, dead and alive plant material, and fungi. They hide under rocks or logs during the day, and come out during spells of rain or at night to feed.
It is found in many differing sites where there is plentiful vegetation like woodlands, fields and gardens. Most likely native, common and widespread in southern Britain.
Photograph of Large Red Slug (Arion (Arion) rufus), taken July 2016, rear garden, Staffordshire. © Pete Hillman 2016. Camera used Nikon D3200, with Sigma 105mm macro lens.
Following The Snail Road
Strawberry Snail (Trochulus striolatus)
It still never fails to amaze and fascinate me how Mother Nature has created so many diverse forms of life. And how these differing forms of life have evolved and adapted to their given environments in order to survive the rigors of life. Take the shell of this Strawberry Snail, how beautifully formed and crafted it is, how fine and delicately sculptured, taking the artist millions of years to perfect. Yet, the work is never complete, such is evolution.
I came across the snail pictured in the above two photographs as it was going down to the pond this morning. It is a relatively small snail with a shell diameter of around 12mm.
They are found in woodland, hedgerows and gardens. Common and widespread, but scarce and localised in Scotland.
Photographs taken May 2014 and July 2016, rear garden, Staffordshire.
Garden Snail
Cornu aspersum
You only have to pop out into your garden on a rainy day, or venture out during the night hours to find one of these slippery creatures going for your plants. This morning I happened to move my bird bath and there he was, hunkered down and sheltered for the day. However I awoke him, and as grumpy as he was (he blew bubbles at me), he obliged me a photo shoot between rain showers.
The shell of this snail can be marbled brown, black or yellow-ochre, and has fine wrinkles. Shell diameter 40mm.
Individuals contain both reproductive organs and are capable of self-fertilisation, although cross-fertilisation is the normal way.
They live in quite varied habitats, from woodland and hedgerows, to gardens and allotments, where they can be serious pests. Mainly feeding nocturnally, or after rain, they consume various plants, and can do a lot of damage. Common and widespread throughout lowland Britain, absent from most of Scotland.
Photographs taken July 2016, rear garden, Staffordshire.
Flat Periwinkle
Littorina obtusata
The colour of the shell of this small snail varies depending on its habitat, and it can be green, orange, yellow, brown or black. There are also banded and chequered patterned forms. The head tentacles of the animal have two lines along them. The shell is finely reticulate. Shell height up to 1.5cm.
Found on the middle to lower shower on large brown seaweeds such as Egg Wrack (Ascophyllum nodosum) and Toothed Wrack (Fucus serratus) on which it feeds. Common on widespread throughout.
Photographs taken August 2015, rockpool, Meadfoot Beach, Torquay, Devon.
Delicate Balance of Life
I found these tiny pearlescent eggs tucked away in a small niche under a rotting log. I think they are slug eggs, of what species I have no idea as I have several in my garden. I was and still am so a taken at how fragile-looking they are, how beautiful they are in the light, and yet they are well protected and suited to bring forth new life.
Photograph taken March 2014, rear garden, Staffordshire.
Rounded Snail
Discus rotundatus
I find it quite amazing what you can discover by the simple act of turning over a log.
Also called the ‘Rotund Disc Snail’, this is a very small snail with 6 tightly packed whorls. The flattened shell is reddish-brown with darker cross bands. The body of the animal is bluish black on the upperside and pale below. Shell diameter 7mm.
Found in gardens and woodland under rocks and logs, and amongst leaf litter. Common and widespread in lowland areas.
Photograph taken March 2014, found under log, rear garden, Staffordshire.
White-lipped Snail
Cepaea hortensis
As much as I love my garden, these slimy creatures seem to love it more – they are slowly, but surely chomping their way through it!
The shell of this snail is quite variable, ranging from all over yellow to yellow with dark brown spiral bands. The lip of the shell is almost always white. Shell diameter 16 to 20mm.
They can live for up to 3 years, and are found in gardens, woods and hedgerows. It is actve during the day in wet and mild conditions, found resting or feeding on vegetation. Common and widespread throughout Britain and Ireland.
Photographs taken June 2014, rear garden, Staffordshire.