Rhipidium knappi Brachiopod

Somewhat rare brachiopod fossil found in the Silurian Louisville Limestone which is known more for its corals. This fossil appears to some sort of Pentamerus but after some research it might be a Rhipidium knappi named by Hall and Whitfield.  The Index Fossils of North America names it being found in Kentucky (Louisville Limestone) and west Tennessee (Brownsport).  Might also be under the name Hall gave in in 1872 as Pentamerus knappi or his 1875 identification Pentamerus nysius var. crassicostus.

See images of it in the Henry Nettelroth (1835-1887) book on Kentucky Fossil Shells (1889): CLICK HERE

Nereidavus invisibilis? Scolecodont

This fossil appears to be a Nereidavus invisibilis? scolecodont found in the Silurian Waldron Shale of Clark County, Indiana, USA.  The fossil was found on top of another fossil as can be seen in the second picture.  The second fossil is a crinoid holdfast.

Thanks to Kenny for the pictures and identification.  See other possible scolecodonts found in the Waldron Shale: CLICK HERE and CLICK HERE.

Wikipedia has pictures of the modern sandworm Alitta virens (old genus name Nereis): CLICK HERE

Sieberella roemeri? Brachiopod

A mold of the internal structure of what I think is a Sieberella roemeri? brachiopod.  Fossil found in the Silurian Waldron Shale of Clark County, Indiana, USA.  The Index Fossils of North America list the genus Sieberella named by Oehlert in 1887.  The species was named by Hall and Clarke and is similar to a Gypidula coeymanensis and also was referred to as a Pentamerus sieberi by Buch.

This particular brachiopod is hard to find and so far I have only found two with them both being internal impression of one valve.  Fossil marks the 19th brachiopod species identified in the Waldron Shale.  See the others at this posting: CLICK HERE