Sponges are locally common as fossils. They are composed a skeletal elements called spicules. Some were composed of calcium or silica/opal. Organic sponges (like the bath sponge) are rare as fossils as they are/were easy to decompose after death.
Stromatoporoids are an extinct group that paleontologists wrestled with their classification for over a hundred years. They were a type of sponge that incorporated calcium into the colony’s structure like corals. More information is before their photos start.
Photos of Sponges & Stromatoporoids
Preservation Key: C = Calcified, Ph = Phosphatic, P = Pyritized, S = Silicified, 1= w/o, matrix, 2 = w/ matrix
PORIFERA Period Location Preservation
Astraeospongia meniscus (Roemer) – Beech River Formation, Middle Silurian, Decatur Co., TN – S,C,1
Astylospongia verrucosa – Beech River Formation, Middle Silurian, Decatur Co., TN – S,C,1
Carpomanon stellatim-sulcatum (Roemer) – Beech River Formation, Middle Silurian, Decatur Co., TN – S,1
Dystactospongia madisonensis (Foerste) – Upper Ordovician, Jefferson Co., IN & Washington Co., KY – C,2
Heterospongia? Whitewater & Bull Fork Fms., Upper Ordovician, Jefferson Co., IN & Washington Co., KY – C,S,1
Hindia sphaeroidalis (Duncan) – Bob Formation, Middle Silurian, Decatur Co., TN -S,C,1
Hindia sphaeroidalis (Duncan) – Beechwood Limestone, Givetian, Middle Devonian, Bardstown, Nelson Co., KY – S,1,2
Hexactinellid (glass) sponges, matts and holdfasts – Muldraugh Formation, Osagean, Middle Mississippian, Hardin Co., KY -C,P,2
Palaeomanon cratera (Roemer) – Beech River Formation, Middle Silurian, Decatur Co., TN, S,1
Palaeomanon elongatum Howell – Beech River Formation, Middle Silurian, Decatur Co., TN – S,1
Unidentified loose spicules – Salem Limestone, Middle Mississippian, Floyd Co., IN – C,1
STROMATOPOROIDS Middle Devonian IN,KY C,S,1,2
The extinct sponges are difficult to identify when well-preserved and impossible when poorly preserved. I used Galloway & St. Jean for the Jeffersonville Limestone and Birkhead for Missouri stromatoporoids. My identification is ‘best guess’ by comparing photos of thin-sections from original sources. Names without photos I have in my collection but they haven’t been photographed.
Amphipora ramosa (Phillips) – Jeffersonville Limestone, Middle Devonian – IN, KY, C, S,1
Anstylostroma columnare (Parks) – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Anstylostroma dupontense Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Anstylostroma laxum (Nicholson) – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Anstylostroma subcolumnare Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Anstylostroma vermiculosum Birkhead – Calloway Limestone, Middle Devonian, Montgomery Co., Missouri – C,1
Hermatostroma insulata Birkhead – Calloway Limestone, Middle Devonian, Callaway Co., Missouri – C,1
Parallelopora catenaria Birkhead? – Calloway Limestone, Middle Devonian, Callaway Co., Missouri – C,1
Parallelopora eumamillata Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Parallelopora typicalis Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Stromatoporella eumaculosa Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Strictostroma jeffersonvillense Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Stromatoporella parasolitaria Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Syringostroma radicosum Galloway & St. Jean – Jeffersonville Limestone, Middle Devonian – IN, KY, S,1
Unidentified from Beechwood Limestone Middle Devonian IN,KY C,S,1,2
Stromatoporoid/rugose coral epifaunal associations, Middle Devonian IN, KY S,1
Unidentified Stromatoporoids (probably undescribed) Middle Silurian KY S,1
Aulacera plummeri, nodulosa, etc. Upper Ordovician KY C,1,2