Leptaena depressa brachiopod from Wenlock Fm

An ubiquitous member of many faunal assemblages of the early Paleozoic is Leptaena. It must have been quite the generalist because I've found it in rocks from the Ordovician through the Devonian. The specimen below is Leptaena depressa from the Silurian aged (Wenlock epoch, Sheinwoodian to Homerian stage), Wenlock formation near Dudley, England. The shell is rectangular in shape with wavy growth lines and very fine radial ribs. Most specimens also have a feature where the pedicle and brachial valves are equal until the edge where they meet. At this point the valves make a sharp turn downwards all along the margin except at the hinge line. In some specimens this can be quite developed and the shell will have a triangular shape in profile.

My theory is that these brachs were attached to a hard substrate for most of their lives until they got too big and the pedicle muscle couldn't hold them upright. The shell them fell over onto the pedicle valve but the animal was still alive. Thus the shell kept growing "upwards" towards the current.

Pedicle valve

Anterior

Brachial valve

Posterior

Profile

I've found other examples of the genus in the Irondequoit limestone & Haragan Formation.

Dalejina hybrida brachiopod from the Wenlock Fm.

Dalejina is a Silurian aged brachiopod that, to me, resembles the genus Rhipidomella that is more commonly found in the Devonian. The specimen below is Dalejina hybrida from the Wenlock formation (Wenlock epoch, Sheinwoodian to Homerian), near Dudley, England. The shell is rounded but slightly oblong with fine raidial ribs on the surface and occasional growth lines. There is a small triangle shaped interarea at the posterior of the pedicle valve as well.

Brachial valve

Anterior

Pedicle valve

Anterior

Profile

I've found a small shell in the Waldron shale of Indiana that I think is Dalejina and you can see that blog post here.

Anastrophia deflexa brachiopod from the Wenlock Formation

This is Anastrophia deflexa from the Silurian aged Wenlock formation, near Dudley, England. The shell looks very similar to Plecatrypa in size and shape but does not have the prominent growth lines. It has strong, coarse ribs, a shallow sulcus and lacks a visible interarea. I have posted before about a similar species from the Waldron shale: Anastrophia internascens.

Brachial valve

Anterior

Pedicle valve

Posterior

Profile

Plecatrypa imbricata brachiopod from the Wenlock fm.

Plecatrypa imbricata from the Silurian aged Wenlock formation (Wenlock epoch, Sheinwoodian to Homerian stage), near Dudley, England. The shell has a spirifer type shape with a wide hinge line and deep sulcus. It differs in that the pedicle valve does not have a triangular shaped opening for the pedicle muscle but rather a circular opening more typical of Rynchonellids. The shell also features strong, coarse ribbing and prominent growth lines. I have found this same genera in the Irondequoit Limestone of New York here.

Brachial valve

Anterior

Pedicle valve

Posterior

Profile

Resserella canalis brachiopod from the Wenlock Fm.

This is the brachiopod Resserella canalis from the Silurian Wenlock formation (Wenlock series, Sheinwoodian to Homerian stage), near Dudley, England. The Pedicle valve is very convex and has a curved beak. The brachial valve is flat to slightly convex. Radial ribs are fine and only minor growth lines are visible. This is a widespread genera during the Silurian and I've found the similar looking species Parmorthis waldronensis in the Waldron Shale and, Resserella elegantula, from the Irondequoit Limestone (both of which are similar in age to the Wenlock formation).

Brachial valve

Anterior

Pedicle valve

Posterior

Profile

Sphaerirhyncia wilsoni brachiopod from the Wenlock formation

I'm kicking off a series of posts featuring brachiopods from the classic Wenlock formation of England with Sphaerirhyncia wilsoni.This brachiopod has a rounded shell with a shallow but wide sulcus. Ribbing is even but coarse and there are fine growth lines preserved as well. Note the bryozoan epibiont in the first image.


Brachial valve

Anterior

Pedicle valve

Posterior

Profile

This specimen came from the Silurian aged (Wenlock series, Sheinwoodian to Homerian stage) Wenlock formation near Dudley, England.

I've posted a similar specimen, Sphaerirhynchia lindenensis, from the lower Devonian (Lochkovian stage) Haragan formation of Oklahoma, here.

Rhyncholampas gouldii echinoid from Florida

Here we have a Rhyncholampas gouldii echinoid from FL. It was found in the Oligocene aged Suwannee Limestone southeast of Tallahassee. It is very similar in appearance to the genus Hardouinia (Cretaceous) but is found much later in the geologic column.

Adapical surface (top)

Anterior

Right profile

Posterior

Left profile

Adoral surface (underside or bottom)

The label that was originally included with this specimen listed it as Rhynchopygus but that genus is only valid in the late Cretaceous of Europe.

Scaphite hungadrianus ammonite from Hungary

This is the last of the ammonites that I received from my Hungarian friend. Scaphite hungadrianus is a heteromorph type ammonite. This means it's shell does not form a neat spiral that is contained in a single plane. The ammonite started out with a normally coiled shell but then at some point it abandoned the coil and grew straight for a bit before returning to a coil. This is best illustrated in the third picture below. The specimen comes from near Pénzesgyőr, Hungary and was found in sediments from the Aptian stage of the Cretaceous.

I found a cool series of videos on You Tube that were created by a local fossil hunter in Hungary. One of them focuses on collecting at Pénzesgyőr.
Thank you Karoly for the cool specimen!

Salaziceras salazacense ammonite from Hungary

This is the ammonite Salaziceras salazacense ammonite from Pénzesgyőr, Hungary. It was collected from Cretaceous (Aptian stage) aged rocks. It is nicely detailed with some of the sutures visible on the back. It was among the fossils I received from my friend Karoly in Hungary.

Arbacina monilis echinoid from Hungary

The wee regular echinoid pictured below is Arbacina monilis from the Eocene near Nyirád, Hungary. I received them as part of an exchange with a collector in Hungary. The fossils have a bit of matrix on them still but you can clearly see the tubercles (the round bumps that the spines attach to). The fossils are from the Badenian stage of the Miocene which corresponds to the Langhian stage of the ICS).

Apical side

Oral side

Thanks to Karoly for the fossils!