Macraster elegans (Shumard, 1854)

Remarks

• Collector:     Keith Minor
• Formation:   Washita Group, Georgetown Limestone
• Location:      Williamson County, Texas
• We must thank Vic Wright with Black Creek Fossils (*link dead on last check 02/13/08) for professionally preparing this specimen.  Great job Vic!  Sorry about the small nick next to the periproct.  That was my bad.
• A comment on the nomenclature is in order here (see refrences below).
• Roemer named several toxasterines "texanus".  The problem created is that Roemer's "Hemiaster texanus" is now considered Macraster texanus, and Shumard's holotype of elegans is poorly described/figured.  Also, Böse has what looks like an elegans, but identifies it as cfr. texanus.  Confused yet? 
• The name Macraster texanus (Roemer, 1849) is preoccupied (we have a M. texanus on cf.com for comparison), so this specimen can't be called texanus, and all indication in the literature is that the above specimen is conspecific with Shumard's elegans.
• The photos in Adkins (1928, plate XIV, fig. 4-see below), Adkins & Winton (1920, plate 8, fig's 3 and 4), Bullard (1926, plate XVII, fig's 1 and 2), and Bybee & Bullard (1927, plate 5, fig's 1 and 2) all confirm that our Georgetown specimen is indeed elegans (a great lateral view of M. elegans can be found in Bybee & Bullard, which further confirms the ID).
• Bose's specimen from Chihuahua, Mexico is therefore an elegans as well.

General Info

Synonyms (older names and misidentifications in the literature)

• fossil hamburger patty

• 1854 Hemiaster elegans Shumard

• 1910 Macraster cfr. texanus (Shumard); Böse

• 1920 Macraster elegans (Shumard); Adkins & Winton

• 1925 Macraster elegans (Shumard); Lambert & Thiery

• 1927 Macraster elegans (Shumard); Lambert

• 1928 Macraster elegans (Shumard); Adkins

• 1930 Macraster elegans (Shumard); Adkins

• 1987 Macraster elegans (Shumard); Akers & Akers

Stratigraphic Occurrence

• Washita Group, Fort Worth Limestone of north Texas

• Washita Group, Duck Creek Limestone of north Texas

• Washita Group, Georgetown Limestone of central Texas

• Washita Group, Caddo Limestone of southern Oklahoma

Age

• Macraster elegans (Shumard) occurs in the Mortoniceras equidistans (Cragin) and Mortoniceras (Angolaites) lasswitzi (Young) zones, Early Late Albian Stage (~100-98 mya).

Geographic Occurrence (by no means an all-inclusive list)

• Chihuahua, Mexico

• Cooke County, Texas

• Marshall County, Oklahoma

• Tarrant County, Texas

• Williamson County, Texas

Remarks

         For identification and descriptions, see:

• Adkins, W. S.  1928.  Handbook of Texas Cretaceous Fossils.  University of Texas Bulletin 2838, 295, plate XIV, fig. 4.

• Adkins, W. S.; Winton, W. M.  1920.  Paleontological Correlation of the Fredericksburg and Washita Formations in North Texas.  University of Texas Bulletin 1945, 53 and 54; plate 8, fig's 3 and 4.

• Bullard, F. M.  1926.  Geology of Marshall County, Oklahoma.  Oklahoma Geological Survey Bulletin 39; plate XVII, fig's 1 and 2.

• Bybee, H. P.; Bullard, F. M.  1927.  The Geology of Cooke County, Texas.  University of Texas Bulletin 2710; plate 5, fig's 1 and 2.