Latimeria

Latimeria
Comoros coelacanth ( Latimeria chalumnae ). Preparation of a female 170 cm long and 60 kg heavy, exhibited in the Vienna Natural History Museum
Systematics
Superclass : Jaw mouths (Gnathostomata) Class : Meat finisher (Sarcopterygii) Subclass : Actinistia Order : Quastenflosser (Coelacanthiformes) Family : Latimeriidae Genre : Latimeria
Scientific name of the  family
Latimeriidae
Berg , 1940
Scientific name of the  genus
Latimeria
Smith , 1939

Latimeria is the only extant species of Quastenflosser (Coelacanthiformes). It got its name after the museum curator Marjorie Courtenay-Latimer , who in 1938 discovered a specimen ( Comoros coelacanth ( L. chalumnae ))caught by fishermenin the area of East London . Until then, this subclass of the meat finisher (Sarcopterygii) was considered to be extinct. Named the discovery in 1939 of the ichthyologists James Leonard Brierley Smith .

The genus has long been described as monotypical and then consisted only of the Comoros coelacanth. In the 1990s, however , another coelacanth population was discovered thousands of kilometers away from the home of the Comoros coelacanth in the Celebes Sea on the coast of the Indonesian island of Sulawesi . This species is called Manado coelacanth ( Latimeria menadoensis ) after the place of discovery .

Latimerias have a small, simple and elongated brain with a length of about 40 mm, a maximum width of 14 mm and a height of 10 mm. It takes up only 1/100 of the volume of the brain cavity in the skull, the rest of the space is filled by a fat-like substance. Morphologically, some parts of the brain are similar to those of cartilaginous fish, others to those of lung fish and actinopterygii. There are no similarities to the amphibian brains.

Systematics

The genus Latimeria includes the following two recent species :

German name	Scientific name	distribution	Hazard level Red List of IUCN	Remarks	image
Comoros coelacanth	Latimeria chalumnae Smith , 1939	southwest Indian Ocean	( Critically Endangered )	up to 2 meters in length
Manado coelacanth	Latimeria menadoensis Pouyaud , Wirjoatmodjo , Rachmatika , Tjakrawidjaja , Hadiaty & Hadie , 1999	near Sulawesi (Indonesia)	( Vulnerable - endangered)	up to 1.5 meters in length

In January 2020, a coelacanth found 750 km east of Sulawesi on the coasts of western New Guinea was announced. The animals are similar to the Manado coelacanth, but a genetic difference of 1.8% suggests that the fish off the coasts of northern Sulawesi and those on the coast of New Guinea separated from each other 13 million years ago, and that the New Guinean population may have represents a cryptic , previously undescribed species.

Web links

Commons : Latimeria  - collection of images, videos and audio files

• Latimeria on Fishbase.org (English)
• Latimeria mania A relic from the past becomes famous , scinexx - the knowledge magazine

Individual evidence

1. ^ R. Nieuwenhuys, JPM Kremers, C. van Huizen: The brain of the crossopterygian fish Latimeria chalumnae: a survey of its gross structure. In: Anat Embryol (Berlin). 151, 1977, pp. 157-169. springerlink.com (English).
2. ↑ Latimeria chalumnae in the Red List of Threatened Species of the IUCN 2000. Posted by: Musick, JA, 2000. Accessed January 15, 2018th
3. ↑ Latimeria menadoensis in the endangered Red List species the IUCN 2008. Posted by: Erdmann, M., 2008. Accessed December 18, 2012 found.
4. ↑ Kadarusman, Sugeha, HY, Pouyaud, L., Hocdé, R., Hismayasari, IB, Gunaisah, E., Widiarto, SB, Arafat, G., Widyasari, F., Mouillot, D. & Paradis, E. ( 2020): A thirteen-million-year divergence between two lineages of Indonesian coelacanths. Scientific Reports, 10: 192. DOI: 10.1038 / s41598-019-57042-1 (English).