Coelacanth

Coelacanth
(image here)
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sarcopterygii Order: Coelacanthiformes Family: Latimeriidae Genus: Latimeria
Binomial name Latimeria chalumnae Latimeria menadoensis

Coelacanths (the name means "hollow spine" in Greek) are fish-like creatures with the pectoral and anal fins on fleshy stalks, and the tail fin divided into three lobes, the middle one of which also has a stalk. About 125 species are known from fossils; they were considered to be index fossils (i.e. they indicated the age of the rock), extinct since the end of the Cretaceous, until a live one turned up off the east coast of South Africa in 1938. Coelacanths can be found in the Comoros, Sulawesi (Indonesia) and St. Lucia Marine Protected Area (South Africa).

History of the discovery

Comoros: First findings

Marjorie Courtenay-Latimer with the first Coelacanth

The gombessa (Latimeria chalumnae) was found by Marjorie Courtenay-Latimer in 1938. A fishing boat caught sharks near the Chalumna River, and Latimer, who was curator of a museum in East London and often looked for odd fish in the harbor, saw a blue fin under them. She pulled the fish out of the pile and brought it to the museum to find out what kind of fish it was. Professor J.L.B. Smith, the scientist she consulted, was surprised to see the fish because it looked like the coelacanths which were known only from fossils.

A worldwide search was launched for more coelacanths, with a reward of 100 British pounds. Fourteen years later, they were found in the Comoros. The Comorans, in port of Mutsamudu on the Comorian island of Anjouan, were puzzled that someone would pay big money for what the locals called a "mame" or "Gombessa", an inferior fish that their fishermen occasionally caught by mistake.

They now understand the significance of their endangered species and have a program in place to return any accidentally caught gombessa to deep water so that it can survive.

Smith, who died in 1968, wrote his account of the coelacanth story in the book Old Fourlegs, first published in 1956. His book Sea Fishes of the Indian Ocean, illustrated and co-authored by his wife Margaret, remains the standard ichthyological reference for the region.

Sulawesi, Indonesia

In 1997, Arnaz and Mark Erdmann were traveling on honeymoon in Indonesia and saw a strange fish entering the market at Manado Tua, on the island of Sulawesi. Arnaz Erdmann recognized it as a gombessa, but it was brown, not blue. (The Erdmanns did not realize this was a new species until an expert saw their photo on the Web.) DNA-testing revealed that this species, called rajah laut by the Indonesians, are not related to the Comorian population. It was given the scientific name Latimeria menadoensis.

St. Lucia Marine Protected Area, South Africa

In South Africa, the search continued on and off over the years. One diver, 46-year-old, Riaan Bouwer, lost his life exploring for coelacanths in June 1998. On October 28th, 2000, just south of the Mozambique border, in Sodwana Bay in the St. Lucia Marine Protected Area, three pleasure divers - Pieter Venter, Peter Timm and Etienne le Roux - made a dive to 104 metres and suddenly spotted a coelacanth. Without cameras, the group decided to return.

Calling themselves SA Coelacanth Expedition 2000 the group, with several additional members, returned and on November 26, they performed a first dive without seeing coelacanths. The next day Pieter Venter, Gilbert Gunn, Christo Serfontein and Dennis Harding, went down again. Moving from cavern to cavern, they found three coelacanths. The largest was between 1.5 and 1.8 metres long, the other two 1.2 metres and 1 metre. The fish swam heads down and appeared to be feeding off of ledges. The cameramen took video footage and photos. Then disaster struck. Assisting Christo, who suddenly passed out under water, 34-year-old Dennis Harding rose to the surface with him in an uncontrolled ascent. Harding complained of neck pains and died in the boat. Apparently, he had suffered a cerebral embolism. Christo recovered after being taken underwater for recompression.

However, the find was big news in South Africa. In March-April 2002, the Jago Submersible and Fricke Dive Team descended into the depths off Sodwana and observed 15 coelacanths, one pregnant. Tissue samples were taken using a dart probe.

External links

• [1] Jerome F. Hamlin's Coelacanth Rescue Mission
• [1] South African Coelacanth Conservation and Genome Resource Programme