What’s this? Receptaculitids aka Sunflower Sponges

From the Whitewater State Park Fossil ID Sheet

Whitewater State Park Fossil ID Sheet

This post is meant to get your eye familiar with “seeing” receptaculitids (or recepts as most people call them), also called Sunflower Sponges. Although, the latest thinking is that they are an algae.

NOTE OF INTEREST: Several decades ago these were reclassified as FISHERITES – However, for whatever reason the renaming hasn’t caught on yet and most fossil collectors are still using the name Receptaculitids.

Complete recepts are rather unusual and on ebay I have seen them sell for from $30 to $75 depending on size and condition. Condition being the most important factor. They weather very quickly.

I found this on Google Images and thought it was fascinating!

Nearly all of the pictures you can make larger for closer examination by tapping them. Not large enough? On most computers there is a “view” function in the upper left hand corner, try 200% or 400% for closer examination.

I have collected, or found and can’t collect, all of these in the last 12 months.

Ordovician

Galena Formation

Fillmore County, MN

A complete recept, note the “eye” of the flower.

Nearly complete -water worn.

Complete

Was a beautiful complete recept, I left it out just one winter and look what happened!

Half of one with eye

Edge of the half on left.

Cross section and top

NEGATIVE impression of a recept.

These next three images are the best preserved piece of recept

I have ever found showing the internal structure of the fossil.

Cross section

Cross section

Cross section

Cross section

Cross section

Cross section

Cross section

Worn in dry wash

Worn in dry wash on its side.

Recept found on a beach – water worn.

Found on beach – water worn.

Recepticulitids Hang Out Together! 

This is pretty awesome!

I found at least 12 whole recepts in a dry wash across from the

last road cut in the “Village of Fillmore Area Road Cuts” post:

http://www.bluffcountryfossils.net/blog/village-of-fillmore-area-road-cuts/

Note the fenceline supporting posts? Right across from there in the dry wash!

Dry Wash on Cty. 5

Very nice single, but this rock had layers of recepts in it!

Another nice single. Nearly all are more than 12 inches across!

Nice half poking out.

Another nice single.

2 in 1 rock

FIVE! In one rock!