Cardiaster hilli Cooke, 1958
Plate: CaHi-10
Series: Upper Cretaceous Group: Taylor Formation: Anacacho
Locale: Cline Station County: Uvalde Stage: Campanian
Length: 21.1 mm Width: 20.5 mm Height: 10.6 mm
Specimen in photo: USNM 328451 (Paratype)
Repository: National Museum of Natural History (NMNH), Smithsonian Institution
HOLOTYPE INFO:
Holotype: USNM 108702 (implied from Cooke series) or USNM 28451 (Paratype listed); Type description in NJGS Bulletin 61.
Locality: Cline, Uvalde County, Texas (Cooke, 1958)
Systematic Paleontology
CLASS: ECHINOIDEA Leske, 1778
SUBCLASS: EUECHINOIDEA Bronn, 1860
INFRACLASS: IRREGULARIA Latreille, 1825
SUPERORDER: ATELOSTOMATA Zittel, 1879
ORDER: HOLASTEROIDA Durham & Melville, 1957
FAMILY: HOLASTERIDAE Pictet, 1857
GENUS: CARDIASTER Forbes, 1850
SPECIES: Cardiaster hilli Cooke, 1958
TYPE SPECIES: Spatangus granulosus Goldfuss, 1829
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Taylor
Formations: Anacacho Limestone (Cooke, 1958)
Stratigraphic Units: Upper Cretaceous, Campanian
Counties: Uvalde County
DESCRIPTION
TOP: Length, width, height: 21.1 mm × 20.5 mm × 10.6 mm
Top shape: Heart-shaped from top; truncated end at periproct ; Test cordate, weakly emarginate in front, broadly truncated behind, with rounded margins (Cooke, 1958)
Top domed: Highest point anterior of center ; Upper surface inflated; highest point in front of the apex, thence sloping steeply forward and gently backward to the posterior truncation (Cooke, 1958)
Convexity: Sides rounded
SIDE: Ambitus: Rounded sides
Side shape: Highest point anterior of center
BOTTOM: Bottom flat: Flat ; Lower surface flat (Cooke, 1958)
AMB: Amb shape: Unpaired ambulacrum (III) sunken, continuing from front to peristome; Paired ambulacra not sunken (flush)
Amb primary zones: Front columns of pore pairs on paired ambulacra are narrower than rear columns
PORE PAIRS: Shape: Pore pairs elongated
Density variation: Front columns narrower than rear columns in paired ambs
SUTURES: Primary Perforated: No
TUBERCLES: Primary tubercles: Non-perforated, sparse; numbers increase moving away from apical system
APICAL SYSTEM: Size / Location: Located center; not very pronounced ; Central (Cooke, 1958)
Shape: Elongated; separates paired ambulacra away from each other
Genital pores: 4 gonopores ; 4 genital pores (Cooke, 1958)
PERIPROCT (ANUS): Shape & Size: Small, transversely oval
Location: Marginal; located just under the halfway point of height on the truncated end
PERISTOME (MOUTH): Shape: Transversely oval, pointed on ends, curved top
Location: Anterior; located halfway from bottom center and front
Sunken: Only slightly depressed
SPECIMENS STUDIED & CONDITION
Specimen condition: Paratype USNM 328451; Dimensions 21.1 x 20.5 x 10.6 mm .
ETYMOLOGY: Named in honor of Robert T. Hill V, "Father of Texas Geology", who extensively mapped the Texas Cretaceous.
REMARKS & COMPARISONS
Remarks: Cardiaster hilli was first listed as a nomen nudum by Cooke in 1953 (USGS Prof. Paper 254) and formally described in 1958 in the New Jersey Geological Survey Bulletin 61, despite the type locality being in Texas (Cooke, 1958).
Comparisons: Distinguished from Cardiaster leonensis (Washita Group) by having an unpaired ambulacrum that is less sunken and broader at the top edge. C. hilli pore pairs are elongated (vs. rounded in leonensis) and the periproct is oval (vs. round in leonensis) . Cooke (1958) notes it resembles Cardiaster smocki Clark from New Jersey but implies smocki is based on imperfect molds.
Plate: CaHi-10
Series: Upper Cretaceous Group: Taylor Formation: Anacacho
Locale: Cline Station County: Uvalde Stage: Campanian
Length: 21.1 mm Width: 20.5 mm Height: 10.6 mm
Specimen in photo: USNM 328451 (Paratype)
Repository: National Museum of Natural History (NMNH), Smithsonian Institution
HOLOTYPE INFO:
Holotype: USNM 108702 (implied from Cooke series) or USNM 28451 (Paratype listed); Type description in NJGS Bulletin 61.
Locality: Cline, Uvalde County, Texas (Cooke, 1958)
Systematic Paleontology
CLASS: ECHINOIDEA Leske, 1778
SUBCLASS: EUECHINOIDEA Bronn, 1860
INFRACLASS: IRREGULARIA Latreille, 1825
SUPERORDER: ATELOSTOMATA Zittel, 1879
ORDER: HOLASTEROIDA Durham & Melville, 1957
FAMILY: HOLASTERIDAE Pictet, 1857
GENUS: CARDIASTER Forbes, 1850
SPECIES: Cardiaster hilli Cooke, 1958
TYPE SPECIES: Spatangus granulosus Goldfuss, 1829
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Taylor
Formations: Anacacho Limestone (Cooke, 1958)
Stratigraphic Units: Upper Cretaceous, Campanian
Counties: Uvalde County
DESCRIPTION
TOP: Length, width, height: 21.1 mm × 20.5 mm × 10.6 mm
Top shape: Heart-shaped from top; truncated end at periproct ; Test cordate, weakly emarginate in front, broadly truncated behind, with rounded margins (Cooke, 1958)
Top domed: Highest point anterior of center ; Upper surface inflated; highest point in front of the apex, thence sloping steeply forward and gently backward to the posterior truncation (Cooke, 1958)
Convexity: Sides rounded
SIDE: Ambitus: Rounded sides
Side shape: Highest point anterior of center
BOTTOM: Bottom flat: Flat ; Lower surface flat (Cooke, 1958)
AMB: Amb shape: Unpaired ambulacrum (III) sunken, continuing from front to peristome; Paired ambulacra not sunken (flush)
Amb primary zones: Front columns of pore pairs on paired ambulacra are narrower than rear columns
PORE PAIRS: Shape: Pore pairs elongated
Density variation: Front columns narrower than rear columns in paired ambs
SUTURES: Primary Perforated: No
TUBERCLES: Primary tubercles: Non-perforated, sparse; numbers increase moving away from apical system
APICAL SYSTEM: Size / Location: Located center; not very pronounced ; Central (Cooke, 1958)
Shape: Elongated; separates paired ambulacra away from each other
Genital pores: 4 gonopores ; 4 genital pores (Cooke, 1958)
PERIPROCT (ANUS): Shape & Size: Small, transversely oval
Location: Marginal; located just under the halfway point of height on the truncated end
PERISTOME (MOUTH): Shape: Transversely oval, pointed on ends, curved top
Location: Anterior; located halfway from bottom center and front
Sunken: Only slightly depressed
SPECIMENS STUDIED & CONDITION
Specimen condition: Paratype USNM 328451; Dimensions 21.1 x 20.5 x 10.6 mm .
ETYMOLOGY: Named in honor of Robert T. Hill V, "Father of Texas Geology", who extensively mapped the Texas Cretaceous.
REMARKS & COMPARISONS
Remarks: Cardiaster hilli was first listed as a nomen nudum by Cooke in 1953 (USGS Prof. Paper 254) and formally described in 1958 in the New Jersey Geological Survey Bulletin 61, despite the type locality being in Texas (Cooke, 1958).
Comparisons: Distinguished from Cardiaster leonensis (Washita Group) by having an unpaired ambulacrum that is less sunken and broader at the top edge. C. hilli pore pairs are elongated (vs. rounded in leonensis) and the periproct is oval (vs. round in leonensis) . Cooke (1958) notes it resembles Cardiaster smocki Clark from New Jersey but implies smocki is based on imperfect molds.
