Currently showing records 181 - 197 of 197 total

More Info Image Taxa Strat Unit Contributor
Megistocrinus concavus Thunder Bay formation Joseph Koniecki

Submitted on 2012-11-28 by Joseph Koniecki

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This specimen is 3.2 cm across.

Photo title: Crinoid calyx

Taxa present: Megistocrinus concavus

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Placoblastus obovatus Thunder Bay formation Joseph Koniecki

Submitted on 2012-11-28 by Joseph Koniecki

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This specimen is 3.3 cm tall.

Photo title: Blastoid

Taxa present: Placoblastus obovatus

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Megistocrinus multidecoratus Thunder Bay formation David Thompson

Submitted on 2013-01-20 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This is a very large example of the caylx of a Megistocrinus multidecoratus from the Thunder Bay Limestone of Partridge point in Alpena. It weighs 7 ounces and is nearly 2 inches high by 3 inches wide, a monster from this location

Photo title: Large Crinoid Caylx

Taxa present: Megistocrinus multidecoratus

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Aorocrinus cassedayi Thunder Bay formation David Thompson

Submitted on 2013-01-20 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This nearly complete crinoid is disarticulated in parts of the lower stem and the arms have been scraped it appears. Some of the column may still be hidden under the Bryozoan fronds that make up much of the limestone of the matrix which is 7' by 5 1/4' or 18 cm by 13.5 cm. The crown itself is 1 1/2' or 3 cm high and the arms range from 1/2' or 1.2 cm to 1' or 2.5 cm wide.

Photo title: Another almost complete crinoid on matrix

Taxa present: Aorocrinus cassedayi

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Aorocrinus cassedayi Thunder Bay formation David Thompson

Submitted on 2013-01-20 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes:

Photo title: Same crinoid but in black and white to show crown detail

Taxa present: Aorocrinus cassedayi

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Heteroschisma alatus Potter Farm formation Joseph Koniecki

Submitted on 2013-07-23 by Joseph Koniecki

Location (approximate): Alpena, Alpena, MI

Strat unit: Potter Farm formation

Submitter notes: This blastoid is 1.3 cm tall. The side and top view are of the same specimen.

Photo title: Blastoid

Taxa present: Heteroschisma alatus

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Botryocrinus thomasi Partridge Point formation David Clark

Submitted on 2014-05-16 by David Clark

Location (approximate): Alpena, Alpena, MI

Strat unit: Partridge Point formation

Submitter notes: A small calyx with interesting ornimentation from Partridge Point

Photo title: Botryocrinus thomasi calyx

Taxa present: Botryocrinus thomasi

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Myzostomida Potter Farm formation David Thompson

Submitted on 2014-07-08 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Potter Farm formation

Submitter notes: This is an infested crinoid stem with multiple small borings of a parasitic worm: Myzostomida. This has 9 borings in this one stem section. Not too much is known about these galls or tumors as they are also called. They are not too common.

Photo title: Parasitic gall on crinoid columnal

Taxa present: Myzostomida

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Myzostomida Potter Farm formation David Thompson

Submitted on 2014-07-08 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Potter Farm formation

Submitter notes: The Myzostomida are an order of small marine polychaete worms, which are parasitic on crinoids causing gall swelling and holes but rarely leaving any other trace.

Photo title: Parasitic gall on crinoid

Taxa present: Myzostomida

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Megistocrinus nodosus Thunder Bay formation David Thompson

Submitted on 2014-10-02 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This Megistocrinus shows some wear and tear with a number of nodes damaged. It is 3 cm thick by 5. cm wide.

Photo title: Crinoid calyx

Taxa present: Megistocrinus nodosus

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Megistocrinus nodosus Thunder Bay formation David Thompson

Submitted on 2014-10-02 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: Two different sizes of the same species. The larger is in the previous photo, the small one is 3 cm thick by 5. cm wide.

Photo title: Big and small Megistocrinus nodosus

Taxa present: Megistocrinus nodosus

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Thunder Bay formation David Thompson

Submitted on 2017-09-04 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This is a straight comparison of size with my smallest sample and the largest

Photo title: The Little and the big.

Taxa present:

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Partridge Point formation David Thompson

Submitted on 2017-04-07 by David Thompson

Location (approximate): Alpena, Alpena, MI

Strat unit: Partridge Point formation

Submitter notes: This is a very small Placoblastus obovatus at just 17.3 mm long and 8.8 mm wide. The average is about 3.5 cm but they can be very much larger! When small these can be confused with the Neucleocrinus melonformis from the same formations

Photo title: Baby Placoblastus

Taxa present:

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Hyperoblastus bassleri Thunder Bay formation Mike Palescuk

Submitted on 2014-12-06 by Mike Palescuk

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: Found by Bob Boyd, May 2014

Photo title: Blastoid

Taxa present: Hyperoblastus bassleri

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Platyceras indianaensis Thunder Bay formation Joseph Koniecki

Submitted on 2015-11-05 by Joseph Koniecki

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: This species is rare in the Traverse Group. This specimen has two of its spines still attached. The gastropod is 4.3 cm across including the spine.

Photo title: Gastropod with spines

Taxa present: Platyceras indianaensis

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Aulacophyllum hemicrassatum Thunder Bay formation Joseph Koniecki

Submitted on 2016-02-08 by Joseph Koniecki

Location (approximate): Alpena, Alpena, MI

Strat unit: Thunder Bay formation

Submitter notes: These corals are not attached at the bottom. It appears that they may have grown up along side of each other and been buried together. The corals are about 10-12 cm in height.

Photo title: Group of Corals

Taxa present: Aulacophyllum hemicrassatum

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Spinocyrtia clintoni Norway Point formation Joseph Koniecki

Submitted on 2018-03-13 by Joseph Koniecki

Location (approximate): Alpena, Alpena, MI

Strat unit: Norway Point formation

Submitter notes: The brachiopod is 2.7 cm across.

Photo title: Brachiopod

Taxa present: Spinocyrtia clintoni

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