Hemiaster whitei (Clark, 1891)

Remarks

• Collector:      Keith Minor
• Formation:    Fredericksburg Group, Goodland Formation
• Location:      Tarrant County, TX
• Dimensions:  lt = 20 mm, ht = 13 mm (tallest part), wdt = 19 mm (widest part)

General Info

Synonyms (older names and misidentifications in the literature)

• 1857 Toxaster elegans Conrad
• 1891 Epiaster whitei Clark
• 1893 Epiaster whitei Clark; Clark
• 1893 Epiaster hemiasterinus Cragin
• 1894 Epiaster hemiasterinus Cragin; Cragin
• 1901 Epiaster whitei Clark; Hill
• 1915 Hemiaster whitei Clark; Clark & Twitchell
• 1927 Hemiaster whitei Clark; Lambert
• 1928 Hemiaster whitei Clark; Adkins
• 1947 Hemiaster whitei Clark; Shimer and Shrock
• 1987 Hemiaster whitei Clark; Akers and Akers
• 1989 Hemiaster whitei Clark; Finsley

Stratigraphic Occurrence

• Lower Washita Group, Duck Creek Formation of North Texas
• Fredericksburg Group, Goodland Formation of North Texas
• Fredericksburg Group, Walnut Formation of North Texas
• Trinity Group, Upper Glen Rose Formation of North Texas

Age

• Hemiaster whitei Clark ranges from the Hypacanthoplites comalensis (Scott) zone to the Mortoniceras equidistans (Cragin) zone, late Early Albian Stage to early Late Albian Stage (~108–101 mya).

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

• Grayson County, TX
• Tarrant County, TX
• Wise County, TX

Remarks

         For identification and descriptions, see:

• Clark, W. B.; Twitchell, M. W.  1915.  Mesozoic and Cenozoic Echinodermata of the United States.  United States Geological Survey Monograph 54, 89; plate XLIII, figs 2a–c; plate XLIV, figs 1a–h; plate XLV, 1a–d and 2a–f.