Tuesday 7 September 2021

PHRAGMOTEUTHIS CONOCAUDA

Phragmoteuthis conocauda
A superb specimen of Phragmoteuthis conocauda, (Quenstedt, 1846-49). These ancient marine lovelies had an internal phragmocone and ten arms.

Phragmoteuthis is a genus of extinct coleoid cephalopod known from the late Triassic to the Lower Jurassic. Its soft tissue has been preserved wonderfully. Some rare specimens contain intact ink sacs, arm hooks, and others, gills.

There are some wonderful specimens from the Carnian, Late Triassic outcrops near Lunz, in Lower Austria with wee arm hooks and ink sacs, though the ink now looks like an agglomerate of grains. 

In Toarcian deposits in Southwestern Germany, we find fragments of Phracmoteuthis concocauda with bits of gill preserved. They look remarkably like the gills of octopod and vampyromorph colcoids.

Palaeontologist Jurji (Jura) Jeletzky characterized phragmoteuthids as having a large tripartite, fanlike pro-ostracum forming the longest portion of the shell, attached to about three-quarters of the circumference of a comparatively small breviconic phragmocone with short camerae and superficially belemnitid-like siphuncle.

Add that to an absent or much-reduced rostrum at the apical part of the phragmocone, belemnite-like arm hooks, an ink sack, beaks resembling those of recent teuthids, and a muscular mantle.

Think early squid. These are their great great grandparents. 

This specimen is in the collections of the University of Oslo Natural History Museum, Norway's oldest and largest museum of natural history in the lovely neighbourhood of Tøyen near Grünerløkka in Oslo. If you visit, check out the nearby Munch Museum to see some of Edvard Munch's work.