Engonoceras hilli Böhm, 1898

Remarks

• Collector:    Bill Jolley
• Formation:  Fredericksburg Group, Goodland Formation
• Location:     Tarrant County, Texas
• E. hilli Böhm is a smoother cousin of E. stolleyi Böhm, with a sharp shoulder, square venter, and very weak ornamentation.

General Info

Synonyms (older names and misidentifications in the literature)

• 1898 Engonoceras hilli Böhm

• 1904 Engonoceras hilli Boehm; Lasswitz

• 1910 Engonoceras stolleyi (Böhm); Grabau and Shimer

• 1921 Engonoceras hilli Böhm; Grabau

• 1927 Metengonoceras hilli Böhm; Adkins

• 1928 Metengonoceras hilli Böhm; Adkins

• 1994 Metengonoceras stolleyi Bohm; Emerson et al.

• 1998 Engonoceras hilli Böhm; Kennedy, Landman, and Cobban

Stratigraphic Occurrence

• Fredericksburg Group, Goodland Formation of north Texas
• Fredericksburg Group, Comanche Peak Formation of north–central Texas

Age

• The range of Engonoceras hilli Böhm does not coincide with the Engonoceras hilli Böhm zone of Young.  Instead it appears to range (slightly younger) from the Oxytropidoceras (Oxytropidoceras) carbonarium (Gabb) zone to the Oxytropidoceras (Oxytropidoceras) powelli (Young) zone, latest Middle Albian to earliest Late Albian (104–103 mya).

Geographic Occurrence (not an all-inclusive list)

• Hood County, TX

• Mills County, TX

• Parker County, TX

• Tarrant County, TX

Remarks

         For identification and descriptions, see:

• Kennedy, W. J.; Landman, N. H.; Cobban, W. A. 1998. Engonoceratid Ammonites From the Glen Rose Limestone, Walnut Clay, Goodland Limestone, and Comanche Peak Limestone (Albian) in Texas. American Museum Novitates 3221.