Description of a tumorous conditon in a gorgonian coral associated with a filamentous green alga
Goldberg WM and Makemson JC. 1981. Description of a tumorous conditon in a gorgonian coral associated with a filamentous green alga. Proceeding of the Fourth International Coral Reef Symposium, Manila. 2:685-697
A tumorous condition affecting the skeleton of a gorgonian coral (Pseudoplexaura spp.) is widespread in the Florida Keys. Incidence of infected colonies, while not strictly density dependent is associated with patch reef areas where Pseudoplexaura densities are greater than 0. 7 m·2. Larger colonies ( >80 em tall) are 2.5 times as likely to possess tumors as smaller individuals. The tumor consists of masses of filamentous green algae that separate the normally tightly apposed laminae of the gorgonian skeleton. Histological examination of these infected areas shows that filaments are primarily confined to the acellular skeletal region and do not appear to affect the functional morphology of the polyps. However, the axis epithelium is anaplastic and apparently dysfunctional. An abnormal proliferation of mesogleal amoebocytes and axial stem canals is also noted. Pure cultures of the algae produce two types of filaments: with amino acids the filaments grow as elongated, cylinc:irical cells with few chloroplats (type I) whereas without amino acids they fill with chloroplasts and become rounded (type II). Zoospores and setae are produced only from type II cells. These cultural observations diagnose the alga a member of the genus Entocladia Reinke 1879. This is the first report of a pathogenic relationship involving a chlorophyte and a coelenterate.
- Type
- Journal Article
- Authors
- Goldberg, Walter; Makemson, John
- Units
- BUIS
- Keywords
- Chemistry, Coral Reefs, Distribution, Ecology, Entocladia, Florida Keys, Gorgonian, Green algae, histology, Pathogen, Pseudoplexaura, Symbiotic