Anenchelum

Anenchelum Temporal range: Early Eocene to Late Miocene PreꞒ Ꞓ O S D C P T J K Pg N
Specimen of A. glarisianum from Switzerland
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Scombriformes
Family:	Trichiuridae
Subfamily:	Aphanopodinae
Genus:	† Anenchelum de Blainville, 1818
Type species
†Anenchelum glarisianum de Blainville, 1818
Species
See text

Anenchelum (Greek for "not an eel") is an extinct genus of cutlassfish known from the early Eocene to the late Miocene. Several species are known that inhabited the northwestern Tethys and later Paratethys region, centered around east-central Europe and west Asia. This genus was synonymized with the extant Lepidopus for a time before being revived as a distinct genus in 1995. ^{[1] [2]}

Taxonomy

The following species are known: ^{[1] [2]}

• †Anenchelum angustumDaniltshenko, 1980 - Early Oligocene of Adygea, Russia (Khadum Formation), potentially Baden-Württemberg, Germany (Raunberg Lagerstätte)
• †Anenchelum eocaenicumDaniltshenko, 1962 - Middle Eocene (Lutetian) of Georgia (Dabakhan Formation)
• †Anenchelum glarisianum de Blainville, 1818 (type species) - Early Oligocene of Canton Glarus, Switzerland (Matt Formation), the Czech Republic (Menilitic Formation) & Romania, and the early to late Miocene of Crete, Greece and the Czech Republic
• †Anenchelum ledneviMenner, 1949 - Early Miocene of Azerbaijan
• †Anenchelum paucivertebraleBannikov & Parin, 1995 - Middle Eocene (Bartonian) of Krasnodar, Russia (Kuma Formation)

Specimen of A. glarisianum from Romania

The species Lepidopus brevicauda from Switzerland and Lepidopus hungaricus from Hungary may also be classified into this genus, but further research is necessary. Indeterminate remains of Anenchelum are known from the Early Eocene of Italy (Chiusole Formation) and the Early Oligocene of Poland. ^[1]

Ecology

Anenchelum was a predatory fish that likely fed on other fish, like its modern relatives. A specimen of A. glarisianum from the Czech Republic contained fossil remains of extinct hake Merluccius latus in its stomach cavity, and fish remains were also recorded in the stomach cavity of an individual from Switzerland. Uniquely, a fossilized individual of A. glarisianum from the Menilitic Formation of the Czech Republic shows evidence of cannibalism, potentially due to an ecological imbalance in the habitat at the time. ^[3] Anenchelum itself fell prey to other animals in its ecosystem; a small individual of A. angustum from Russia is preserved next to the fossilized imprint of a Loligo squid, which appears to have attempted to prey on it before both were fossilized; this specimen is notable for being the first squid body fossil known. ^[4]

References

1. "PBDB Taxon". paleobiodb.org. Retrieved 2024-12-05.
2. Bannikov, A. F.; Parin, N. V. (1995). "Description of a New Species of Scabbardlish (Aphanopinae: Trichiuridae) from the Middle Eocene of the Northern Caucasus, with Restoration of the Validity of the Fossil Genus Anenchelum" (PDF). Journal of lchthyology. 35 (9).
3. Přikryl, T.; Novosad, B. (2009-09-11). "Direct evidence of cannibalism in the Oligocene cutlassfish Anenchelum glarisianum Blainville, 1818 (Perciformes: Trichiuridae)". Bulletin of Geosciences: 569–572. doi:10.3140/bull.geosci.1114. ISSN   1802-8225.
4. Mironenko, Aleksandr A.; Boiko, Maxim S.; Bannikov, Alexandre F.; Arkhipkin, Alexander I.; Bizikov, Viacheslav A.; Košťák, Martin (2021). "First discovery of the soft‐body imprint of an Oligocene fossil squid indicates its piscivorous diet". Lethaia. 54 (5): 793–805. doi:10.1111/let.12440. ISSN   0024-1164.