#852: Xerosecta

There are a number of  Xerosecta, a Genus of terrestrial hairy snails found in various locations about Europe. Many of the species, like this Xerosecta giustii, are on the brink of extinction with many classified as Endangered, some even Critical. Xerosecta are simultaneous hermaphrodites, being able to reproduce both as a male and a female. The so-called "love dart" is a calcareous or chitinous appendage, which develops after the snail's first mating. The courtship dance can last for many hours, with both partners circling one another, making contact with one another, and drawing closer. Eventually they will simultaneously fire their darts, locking together, after which mating can begin.

#831: Whelk

Whelk is a term given to various species of sea snail, generally those that are consumed by humans and other animals.This fellow is an ivory whelk. Unlike their terrestrial kin, marine snails are not hermaphrodites and have distinct genders. True whelks prey on other molluscs, such as other snails, and clams, as well as carrion. For this, he has a very well developed sense of smell and can sense chemical signals from their prey. Once the prey has been located, the Whelk will bore through the shell.  

#803: Violet Sea Snail

I confess, I initially chose the Violet Sea Snail merely for its name and because I never have enough invertebrates for this alphabet. But once I started learning about it, I realised that here was another awesome animal I had never heard of before.

The Violet Sea Snail is a marine mollusc with an unusual hunting technique. He excudes mucus, trapping bubbles of air to create a "raft", to which it clings, upside down. He then travels with the waves and the wind, preying on - get this! - free-floating hydrozoans, such as the Portugese man o' war. All Violet Sea Snails begin life as a male, changing to a female as she ages. Eggs are retained by the female until the larvae hatch.

#706: Snail

The Snail, like the Slug, is a Gastropod Mollusc. They are characterised by the presence of a protective shell, large enough to retereat into. There are many different species of Snails, some not particularly closely related. They can be found in a wide range of habitats: from the oceanic depths, to freshwater ponds, and in almost every terrestrial environment. Many species of terrestrial Snails, like this common garden snail, favour a vegetarian diet, and can be quite destructive on crops and gardens. Others - such as the Rosy Snail - are carnivorous. The Snail's shell is made from calcium, and they are not infrequently found on the sides of houses, where they graze on the stucco. This is not too much of a problem with the regular garden snail,  which is fairly small, but the African giant snail - the size of a mouse - can cause damage.

Other species of snails:
Oahu Tree Snail: Critically endangered, predated on by Rosy Snail.
Dlinzi Pinwheel: Critically endangered, habitat destruction.

#704: Slug

Slug is a name given to apparently shell-less gastropod molluscs. They lead a mostly terrestrial existence, and are prone to dessication - hence they favour a moist environment such as leaf litter, or beneath rocks. Many retain a remnant of their ancestral shell, although this is often internal. Slugs move using their flat underside - known as the "foot". By contracting the muscles and exuding a layer of mucus, they are able to move at a slow but steady pace. This mucus also aids in retaining moisture. Slugs are hermaphrodites and able to reproduce as both male and female. With some species - like this Banana Slug - the penis becomes trapped within the partner's body and must be chewed off before they can separate. After that, the Slug is only able to mate as a female.

Creature Feature #590: Pinwheel

The Dlinza Pinwheel is a strange and beautiful snail, characterised by the bristles radiating from their almost translucent shell. They are found only in the Dlinza forest, in South Africa, an area that measures only 250 hectares. Preferred habitat is coastal scarp forest, where they can be found beneath the low-level leaves, within the leaf litter and under decaying logs. Although the forest is protected, it lies within an area of urban development and the snail is very vulnerable to habitat disturbance and weather fluctuations.

Creature Feature #558: Oyster

Oyster is the common name given to various Families of clam, found in both marine and brackish waters. They are filter feeders, drawing water in through their gills and straining it of nutrients, which are then trasnported to the mouth. Each Oyster is capable of filtering up to 5 litres of water an hour, improving the water quality of their environment. Many species of Oyster are harvested for the food industry, with the internal organs being considered a delicacy and reported to have aphrodisiac properties. They are high in zinc and other nutrients, whilst also being low in calories.

Creature Feature #516: Nudibranch

Nudibranch are a Clade of soft-bodied molluscs, living in the marine environment. There are over 2,300 species recognised and they are all remarkedly strange and colourful. In many cases this colour acts as a warning, for many species of Nudibranch are distasteful or poisonous. All known species are carnivorous, and feed on sponges, hydroids and other primitive marine animals, with some species even seeking larger and toxic prey (like our old friend, the Blue Angel, which feeds on Portugese Man 'o war). CAnnibalism is not unknown, either. Nudibranch are hermaphroditic, but cannot self fertilise.

Creature Feature #497: Nautilus

The Nautilus are primitive members of the Cephalopod Class. He is characterised by his logarithmic spiral shell and mass of tentacles (up to 90). If threatened, he is able to withdraw entirely into his shell, covering it with a hood. Although his tentacles lack the adhesive pads of his relatives, they are ridged to allow him a firm grip on any prey that might come within grasp. He uses these and his powerful bill to rip crustaceans from the rocks to which they might attach themselves.