page updated 06/03/06


Cuphosolenus tarrantensis (Stanton, 1947)



  • Collector:    Farley Katz

  • Formation:  Fredericksburg Group, Goodland Limestone

  • Location:     Tarrant County, Texas


  • Again, we must thank Farley Katz for helping us resolve the taxonomic and nomenclature issues surrounding a Cretaceous fossil from Texas.

  • This species is a member of a group of beautiful winged gastropods.  Although it is particularly common in the lower part of the Fredericksburg Group (we at found ca. 75 in one afternoon's worth of collecting), it's almost always preserved as an internal mold of the spire, so the delicate diagnostic features (outer lip or wing, digits, and ornamentation and siphonal tube) are almost never preserved (typical crummy preservation in the TX Lower K).  This has led to confusion on its classification, and frustration on the part of collectors.

  • Based on numerous specimens that both Farley and wbmster have collected, it's clear that the gastropod is not Aporrhais tarrantensis as originally designated by Stanton, but should be placed in the genus CuphosolenusAporrhais has the outer lip attached to most of the spire, and the digits are wing-like extensions rather than spiny fingers.  Cuphosolenus on the other hand has the classic shape and tridigitate arrangement shown by our reconstruction of C. tarrantensis (top right figure-the extent of the the costae and spiral lines is not known so those details may be off a little). 

  • Also, Sohl and Akers & Akers report it as Arrhoges, which has a wing with a single ridge that terminates to a sharp point.

  • The species reported by Akers & Akers as "Arrhoges sp. A" and "Arrhoges sp. B" are almost certainly Cuphosolenus.

  • A systematic morphological comparison of the Aporrhaids with figures showing the different forms is given in Roy (1994).  See reference below.

  • With regard to nomenclature issues, Stanton reported Cuphosolenus as Cyphosolenus, adding further confusion to the genus.

  • According to Farley, Cuphosolenus Piette, 1876 was emended to Cyphosolenus by Fischer in 1887 without any apparent justification, and the name was retained by Stanton.  According to the ICZN rules Cuphosolenus is valid and takes priority, so we're using the name here.

  • FYI:  Aporrhais ? subfusiformis of Stanton co-occurs fairly commonly with C. tarrantensis.  Although we've never found an outer lip preserved, it's clearly different than C. tarrantensis by is sharper spire, and lack of any hint of a ridge from which the middle digit originates (we'll get a subfusiformis on the site soon).


  • Summary of the described Texas Lower Cretaceous Aporrhaids:

  • Anchura quitmanensis:  designation of holotype is consistent with form for Drepanochilus.

  • Drepanochilus mudgeana:  definitely correct (a fairly common Washita Group gastropod)!  A specimen will be included soon.

  • Drepanochilus kiowanus:  designation of holotype is consistent with form.

  • Aporrhais ? elpasensis:  as indicated by question mark, not enough preserved on holotype to make positive ID on genus.

  • Aporrhais ? kentensis:  not enough preserved on holotype to make positive ID.

  • Aporrhais ? subfusiformis:  not enough preserved on holotype to make positive ID.

  • Aporrhais tarrantensis:  it's Cuphosolenus tarrantensis after critical review of literature and examination of numerous specimens.

  • Arrhoges sp. A and B:  doubtful-they look like typical Cuphosolenus from the lower Fredericksburg Group (not enough preserved to make ID).

  • Arrhoges travisensis:  designation of holotype is consistent with typical form for Arrhoges.

  • Monocyphus brittsi:  definitely correct.

  • Monocyphus singleyi:  definitely correct.

  • Cyphosolenus nuecensis:  taxon is correct, but Cyphosolenus is junior synonym.  Should be Cuphosolenus nuecensis.


General Info


Synonyms (older names and misidentifications in the literature)


  • 1849 Rostellaria sp. ind. Romer

  • 1852 Rostellaria sp. ind. Romer

  • 1947 Aporrhais tarrantensis Stanton

  • 1967 Arrhoges tarrantensis (Stanton); Sohl

  • 1997 Arrhoges tarrantensis (Stanton); Akers and Akers

  • 2006 Cuphosolenus tarrantensis (Stanton); Katz

Stratigraphic Occurrence

  • Washita Group, Fort Worth Formation of North Texas

  • Washita Group, Boracho Formation of Trans-Pecos Texas

  • Fredericksburg Group, Goodland Formation of North Texas

  • Fredericksburg Group, Edwards Formation of North Texas

  • Fredericksburg Group, Comanche Peak Formation of North Texas

  • Fredericksburg Group, Bee Caves Limestone of Central Texas


  • Cuphosolenus tarrantensis (Stanton) ranges from about the Oxytropidoceras (Mirapelia) salasi (Young) to the Mortoniceras (Angolaites) lasswitzi (Young) zone, upper Middle Albian to middle Upper Albian Stage (~105–100 mya).

Geographic Occurrence (not an all-inclusive list)

  • Culberson County, TX

  • El Paso County, TX

  • Erath County, TX

  • Grayson County, TX

  • Somervell County, TX

  • Tarrant County, TX

  • Travis County, TX


Here's one from the Fredericksburg Group, Comanche Peak Formation, Comanche County, Texas (Lee Duchouquette).













        For identification and descriptions, see:

  • Stanton, T. W.  1947.  Studies of Some Comanche Pelecypods and Gastropods.  United States Geological Survey Professional Paper 211, 107; plate 66, fig's 4-6 and 8.

  • Roy, K.  1994.  Effects of the Mesozoic Marine Revolution on the Taxonomic, Morphologic, and Biogeographic Evolution of a Group: Aporrhaid Gastropods During the Mesozoic.  Paleobiology 20(3), pp. 274-296 (see p. 276, fig. 1 for morphologies of the various Aporrhaids).

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