Select the search type
  • Site
  • Web




Lyncina vitellus (Linnaeus, 1758)

Milk Spot Cowrie

Chelsea Waters (2014)



Fact Sheet



Physical Description

Size and Colouration

Shell Morphology


Local Distribution and Habitats

Biogeographical Distribution

Crypsis and Defence

Life History & Behaviour


Sensory System

Growth and Development



Anatomy & Physiology

External Morphology


Evolution & Systematics

Conservation & Threats

References & Links

External Morphology

Shell and Mantle

The external features of L vitellus is characterised by its calcium carbonate shell and protective mantle. Observations in L. vitellus show no clear correlations between sediment colour and shell colour (Savazzi, 1998). The mantle and its associated papillae may have a camouflage function that also reflects feeding type (Savazzi, 1998). The lack of crypsis displayed by the shell may be instead used to 'advertise' these organisms, making them easily recognizable by predators and thus learning to avoid them (Savazzi, 1998). In some cases, the colourful shell pattern in Cypraeans can be confused for a nudibranch which carry nematocysts, or other organisms that live in the same environment (Savazzi, 1998). Different colour patterns displayed in both the mantle and shell may also cause confusion in predators when the sudden withdrawal from an attack exposes a shell that is different in appearance (Savazzi, 1998). 


Papillae size, structure and colouration has been observed to be species-specific and is associated with the ecology and habitat of the animal. However, the exact function of the papillae remains unknown, as mentioned in the Australian literature. Sections were made at the University of Queensland to gain an insight into their structure and subsequent physiology.

Analysis of papillae sections in L. vitellus.
By Chelsea Waters

As a whole, the individual papillae are lined by an epithelium which provides a number of functions (namely secretion, selective absorption, protection, and detection of sensation). Attached to the epithelium are microscopic hair-like structures called cilia (Ciliopathy Alliance, 2010). They may either play a role in respiration (motile cilia) or as a sensory system (non-motile cilia), receiving signals from their surroundings (Ciliopathy Alliance, 2010). Upon closer inspection, goblet cells can be seen between the epithelium. Goblet cells are membrane bound secretory granules filled with mucus (Specian, 1991). Secretion of mucus from goblet cells is elicited primarily by irritating stimuli rather than in response to hormones (Bowen, 1998). Cilia play an important role in detecting these irritations (Ciliopathy Alliance, 2010).

Ciliated epithelium and goblet cells seen in L. vitellus.

The dermis of the papillae contain abundant Meissner’s corpuscle; touch receptors which consist of a number of flattened cell layers, each with an elongated nucleus (Histology, 2005). Distortion of the corpuscle due to pressure stimulates the nerve endings, registering the sensation of touch (Histology, 2005). This may be associated with the triggering of mucus in the goblet cells. However, closer inspections need to made to determine whether it is Meissner’s corpuscle, or merely connective tissue. 

Longitudinal section of L. vitellus papillae (Microscope: 10x0.3). 

Interior of the papillae (Microscope: 20x0.5)

The interior of the papillae contains muscular bands surrounded by connective tissue. These bands may be dermal erector muscles, which extend across the papillae's diameter. They function in mainting the structure of the papillae, whilst also providing active papillary retraction and aiding in mucus release (Allen, 2013). From these observations, it can be determined that the papillae of L. vitellus play an important role in mucus release as an anti-predator defence, as well as a sensory organ for the detection of these predators. However further studies and histological analysis will need to be made in order to precisely determine the function of the papillae in L. vitellus