Loganellia
sp
Agnatha,
Thelodontiformes, Loganiidae
Geological
Time: Middle Silurian (Wenlockian Stage)
Size: Fish
fossil is 48 mm in length
Fossil Site:
Leshmagow, Scotland
Description:
The Thelodontia are a group of fishes most commonly known from their
distinctive tooth-like scales. Indeed the term Thelodont , derived
from Greek, means nipple tooth. The teeth have a characteristic
crown made of dentine. The scales even on a single specimen are
quite variable. Thelodonts are rarely found as complete specimens;
those that are show them to be flattened
fish, many of which were bottom dwellers. Recent finds of intact
specimens from Canada show that they radiated into some deep-bodied
forms that swam freely in the water column. These deep-bodied forms
may have been more closely allied with jawed fishes than their other
relatives. All Thelodonts were extinct by the Upper Devonian.
This
high-quality specimen that has recently been obtained from a 50
year old collection shows the distinctive scales. This fine part/counterpart
example is most distinctive, a rare pair of this rarely-seen taxon.
I’ve included a drawing of the similar Lanarkia. |
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