RESULTS

The venom apparatus of the weever fish (T.vipera) was found to consist of two components:

The venom Gland component (glandular cells and other accessory structures), and the hard component consisting of the opercular spine, all of which is encased in a membrane sheath. This sheath protects these structures from environmental substances and acts as an integral part of the entire venom system.

The venom gland is not one gland but two. The glands are found in the basal grooves of the opercular spine and short way up the lateral groove which runs along the length of the spine extending from the basal groove and terminating a short distance from the spine tip.

                        

The only difference between the two glands is that the gland on the bottom is slightly larger than the gland at the top. The venom gland consists of large globular cells containing the toxin and other cellular components, surrounded by fibres which are in turn surrounded by a membrane sheath.

The venom of the weever fish after staining was found to give a grained appearance, this grained appearance was repeated whether  the venom was contained within the glandular cells or on the outside. As the stain used was Bromophenol blue (A stain specifically for protein) the toxin could be protein based.

The hard part of the venom apparatus was found to consist of three distinct regions:

1) The opercular spine which had a longitudinal groove running along its length terminating a short distance from the tip.

2) Two Basel grooves that connected onto the spinal groove.

3) Opercular plate, where the muscles that raised and lowered the spine were attached to. On the dorsal side no specific attachment point was found although a raised structure was observed that could serve as a muscle attachment point, on the ventral side a raised structure was found which the ventral muscle was attached to.

 

The longitudinal groove narrows towards the end of the spine terminating in a point. The opercular spine was found to have a layered structure, similar to that of a laminated board. One of the spines was found to have a possible deformity in the Basel groove. (See photo below).

The Basel groove on the left of the structure is slightly deformed, in that it has a strut vertical splitting the basal groove in two.