External Morphology & Physiology

As with all Cnidarians, sea anemones display radial symmetry in their body plan, but could also be considered bi-radially symmetrical due to the mesenteries forming as mirror images on opposite sides along the mouth axis.

The specimens found were transparent except for some orange dotted colouration along the simple tapered tentacles and over the oral disc.  A piece of tentacle was dissected off the live specimen and looked under a fluorescing microscope, where the piece was looked at under a TxRed setting, it being exposed to green excitation light, emitting red light.  As the light is in the range of chlorophyll, presence of the red light in place of the cells on the tentacles indicated a presence of a unicellular photosynthetic organism, potentially algae.  Further investigation involved dying a sectioned slice with DAPI, which highlighted that the nucleus when observed under the DAPI setting was independent of the cells when observed under the TxRed setting.  This would indicate that the photosynthetic cells are not only independent but also extracellular and potentially forming a symbiotic relationship.

Images taken at 40x magnification and scale of 10um relates to both images.  Left image depicts cells found on the tentacles overlaid with those same cells imaged under the fluorescing microscope, indicating the presence of photosynthetic cells.  Right image compares the nuclei of the tentacle cells to determine if the photosynthetic cells are intra or extra-cellular.  As the fluorescing cells are external to the nuclei as depicted by the right side overlay image, it would indicate that the photosynthetic cells are extracellular.

The column of the specimen could not be observed due to the flattening of the animal over the oral/aboral axis, however, as a general rule, the column displays a uniform appearance. When retracting, the oral disc, tentacles and capitulum fold into the column and covered by constriction of the oral disc margin created via the sphincter muscle.  As the specimen bears acontia, it is possible that the column also contains cinclides, holes in the column wall that allow the acontia to be projected externally to the animal.