Protocardiaster pocranei Thompson, 2016
Plate: PrPo-10
Series: Lower Cretaceous Group: Washita Formation: Espy
Locale: (private property) County: Hudspeth Stage: Albian
Length: 33.9 mm Width: 34.5 mm Height: 17.4 mm
Specimen in photo: NPL 82993 Holotype
Collector: Frank Crane
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
HOLOTYPE INFO:
Holotype: NPL 82993.
Paratype: NPL 82994.
Locality: Private property, Hudspeth County, Texas.
Stratigraphy: Espy Formation, Washita Group.
SYSTEMATIC PALEONTOLOGY – TAXONOMY
Class: Echinoidea Leske, 1778
Subclass: Euechinoidea Bronn, 1860
Infraclass: Irregularia Latreille, 1825
Superorder: Atelostomata Zittel, 1879
Order: Holasteroida Durham & Melville, 1957
Family: Cardiasteridae Lambert, 1917
Genus: PROTOCARDIASTER Smith & Wright, 2003
Species: Protocardiaster pocranei Thompson, 2016
TYPE SPECIES: Spatangus truncatus Goldfuss, 1829
DIAGNOSIS
A Protocardiaster from the Albian of West Texas characterized by a sharp carina at the deep anterior sulcus and a sloping anterior profile with the apical system at the apex. The test is wider than long.
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Washita
Formations: Espy Formation.
Stratigraphic Units: Lower Cretaceous, Albian.
Counties: Hudspeth.
Abundance: Rare; known from one location.
DESCRIPTION
TOP: Length, width, height: 33.9 mm L × 34.5 mm W × 17.4 mm H. Top shape: Cordate; wider than long. Widest point slightly anterior of midpoint (or slightly above midpoint per text). Anterior sulcus is very deep with a sharp carina. Top domed: Anterior end sloping with apical system at the apex.
SIDE: Ambitus: Positioned 1/3 of height from the adoral surface. Side shape: Very inflated; smaller specimens shaped like a sloping parallelogram and less domed. Posterior end is truncated.
BOTTOM: Bottom shape: Very flat on large specimens; slightly depressed at peristome. Deep rounded keel present on bottom. Plastron: Protosternous plating.
AMB: Amb shape: Paired ambulacra are petaloid, wide, and open-ended. Unpaired ambulacrum (III) is lanceolate, open-ended, and runs for about half the length of the sulcus. Amb arrangement: Paired ambs are lanceolate and only slightly flexuous (weakly bowed); extending 3/4 length to the margin.
PORE PAIRS: Unpaired Amb: Very small, round, almost unnoticeable. Paired Ambs: Elongated.
TUBERCLES: Distribution: Very small and sparse aborally and adorally; larger near margins and along sides of anterior sulcus and apical system.
GRANULES: (Not specified).
FASCIOLE: Marginal: Very pronounced on the sides of the anterior half of the test and below the periproct.
APICAL SYSTEM: Location: Slightly anterior of center (at the apex). Shape: Elongated vertically. Genital pores: 4 gonopores. Plating: Small madreporite.
PERIPROCT (ANUS): Shape: Oval with pointed ends; elongated vertically (slightly taller than wide). Location: Situated just above the midpoint on the posterior truncation; cut into the margin. Visibility: Barely visible from above; clearly visible from the posterior end.
PERISTOME (MOUTH): Shape: Reniform ("renal shaped"); twice as wide as tall. Size: Small.
SPINES: Unknown.
SPECIMENS STUDIED & CONDITION: Three specimens studied. Holotype NPL 82993 and Paratype NPL 82994.
ETYMOLOGY
Named after "Po Crane", the nickname used by the grandchildren of the collector, Frank Crane.
REMARKS & COMPARISONS
Remarks: This species represents the genus Protocardiaster, established by Smith & Wright (2003) for cardiasterids with a marginal fasciole and protosternous plastron.
Comparisons:
Plate: PrPo-10
Series: Lower Cretaceous Group: Washita Formation: Espy
Locale: (private property) County: Hudspeth Stage: Albian
Length: 33.9 mm Width: 34.5 mm Height: 17.4 mm
Specimen in photo: NPL 82993 Holotype
Collector: Frank Crane
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
HOLOTYPE INFO:
Holotype: NPL 82993.
Paratype: NPL 82994.
Locality: Private property, Hudspeth County, Texas.
Stratigraphy: Espy Formation, Washita Group.
SYSTEMATIC PALEONTOLOGY – TAXONOMY
Class: Echinoidea Leske, 1778
Subclass: Euechinoidea Bronn, 1860
Infraclass: Irregularia Latreille, 1825
Superorder: Atelostomata Zittel, 1879
Order: Holasteroida Durham & Melville, 1957
Family: Cardiasteridae Lambert, 1917
Genus: PROTOCARDIASTER Smith & Wright, 2003
Species: Protocardiaster pocranei Thompson, 2016
TYPE SPECIES: Spatangus truncatus Goldfuss, 1829
DIAGNOSIS
A Protocardiaster from the Albian of West Texas characterized by a sharp carina at the deep anterior sulcus and a sloping anterior profile with the apical system at the apex. The test is wider than long.
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Washita
Formations: Espy Formation.
Stratigraphic Units: Lower Cretaceous, Albian.
Counties: Hudspeth.
Abundance: Rare; known from one location.
DESCRIPTION
TOP: Length, width, height: 33.9 mm L × 34.5 mm W × 17.4 mm H. Top shape: Cordate; wider than long. Widest point slightly anterior of midpoint (or slightly above midpoint per text). Anterior sulcus is very deep with a sharp carina. Top domed: Anterior end sloping with apical system at the apex.
SIDE: Ambitus: Positioned 1/3 of height from the adoral surface. Side shape: Very inflated; smaller specimens shaped like a sloping parallelogram and less domed. Posterior end is truncated.
BOTTOM: Bottom shape: Very flat on large specimens; slightly depressed at peristome. Deep rounded keel present on bottom. Plastron: Protosternous plating.
AMB: Amb shape: Paired ambulacra are petaloid, wide, and open-ended. Unpaired ambulacrum (III) is lanceolate, open-ended, and runs for about half the length of the sulcus. Amb arrangement: Paired ambs are lanceolate and only slightly flexuous (weakly bowed); extending 3/4 length to the margin.
PORE PAIRS: Unpaired Amb: Very small, round, almost unnoticeable. Paired Ambs: Elongated.
TUBERCLES: Distribution: Very small and sparse aborally and adorally; larger near margins and along sides of anterior sulcus and apical system.
GRANULES: (Not specified).
FASCIOLE: Marginal: Very pronounced on the sides of the anterior half of the test and below the periproct.
APICAL SYSTEM: Location: Slightly anterior of center (at the apex). Shape: Elongated vertically. Genital pores: 4 gonopores. Plating: Small madreporite.
PERIPROCT (ANUS): Shape: Oval with pointed ends; elongated vertically (slightly taller than wide). Location: Situated just above the midpoint on the posterior truncation; cut into the margin. Visibility: Barely visible from above; clearly visible from the posterior end.
PERISTOME (MOUTH): Shape: Reniform ("renal shaped"); twice as wide as tall. Size: Small.
SPINES: Unknown.
SPECIMENS STUDIED & CONDITION: Three specimens studied. Holotype NPL 82993 and Paratype NPL 82994.
ETYMOLOGY
Named after "Po Crane", the nickname used by the grandchildren of the collector, Frank Crane.
REMARKS & COMPARISONS
Remarks: This species represents the genus Protocardiaster, established by Smith & Wright (2003) for cardiasterids with a marginal fasciole and protosternous plastron.
Comparisons:
- Protocardiaster truncatus & P. cotteauanus: P. pocranei has a more pronounced carina, a wider test, and is more inflated than these European species.
