Cardiaster leonensis Stephenson, 1941
Plate: CaLe-10
Series: Upper Cretaceous Group: Navarro Formation: Corsicana
Locale: Castroville Road County: Bexar Stage: Maastrichtian
Length: 16.1 mm Width: 16.0 mm Height: 7.8 mm
Specimen in photo: USNM 76279 (Holotype)
Repository: National Museum of Natural History (NMNH), Smithsonian Institution
HOLOTYPE INFO:
Holotype: USNM 76279 — National Museum of Natural History, Smithsonian Institution (Stephenson, 1941)
Locality: Castroville Road, Bexar County, Texas (Stephenson, 1941)
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 leonensis Stephenson, 1941
TYPE SPECIES: Spatangus granulosus Goldfuss, 1829
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Navarro (Stephenson, 1941)
Formations: Corsicana Marl (Stephenson, 1941; Cooke, 1953)
Stratigraphic Units: Upper Cretaceous, Maastrichtian (Stephenson, 1941)
Counties: Bexar County (Stephenson, 1941)
DESCRIPTION
TOP: Length, width, height: 16.1 mm × 16.0 mm × 7.8 mm
Top shape: Cordate, with a shallow, rounded frontal notch; upper surface rounded (Cooke, 1953)
Top domed: Slightly higher in front than behind (Cooke, 1953)
SIDE: Truncation: Truncated behind (Cooke, 1953)
BOTTOM: Bottom flat: Oral surface concave (Cooke, 1953)
AMB: Amb shape: Paired petals extending more than halfway to the margin (Cooke, 1953)
Amb primary zones: Anterior poriferous zones straight, narrow; posterior poriferous zones slightly curved forward, much wider (Cooke, 1953)
PORE PAIRS: Shape: Anterior zones pores small and circular; Posterior zones inner pores oval, outer pores elongated (Cooke, 1953)
Density variation: Posterior zones much wider than anterior (Cooke, 1953)
TUBERCLES: Primary tubercles: Tubercles scattered (Cooke, 1953)
Primary Perforated: No
GRANULES: Granules pattern: Fine granulation (Cooke, 1953)
FASCIOLE: Fasciole: Marginal fasciole present (Cooke, 1953)
APICAL SYSTEM: Location: In front of the center (Cooke, 1953)
Shape: Elongated; paired plates arranged in two parallel lines headed by the odd ocular plate (Cooke, 1953)
Genital pores: Four genital plates (Cooke, 1953)
PERIPROCT (ANUS): Shape & Size: Nearly circular; slightly higher than wide (Cooke, 1953)
Location: Terminal; well up on a concave posterior truncation (Cooke, 1953)
PERISTOME (MOUTH): Size: Large (Cooke, 1953)
Shape: Transversely oval (Cooke, 1953)
Location: At the anterior third (Cooke, 1953)
SPECIMENS STUDIED & CONDITION
Specimen condition: Holotype USNM 76279 .
ETYMOLOGY: Named for Leon Creek (Bexar County), which flows near the type locality at Castroville Road (Stephenson, 1941).
REMARKS & COMPARISONS
Remarks: Cardiaster leonensis is described as small for the genus (Cooke, 1953). It was originally described in Stephenson's comprehensive The Larger Invertebrate Fossils of the Navarro Group of Texas (1941).
Comparisons: Compared to Cardiaster hilli (Campanian, Anacacho Fm.), C. leonensis has a more sunken unpaired ambulacrum that is narrower at the top edge. The pore pairs of C. leonensis are much more rounded compared to the elongated pores of C. hilli, and the periproct is nearly circular rather than oval .
Plate: CaLe-10
Series: Upper Cretaceous Group: Navarro Formation: Corsicana
Locale: Castroville Road County: Bexar Stage: Maastrichtian
Length: 16.1 mm Width: 16.0 mm Height: 7.8 mm
Specimen in photo: USNM 76279 (Holotype)
Repository: National Museum of Natural History (NMNH), Smithsonian Institution
HOLOTYPE INFO:
Holotype: USNM 76279 — National Museum of Natural History, Smithsonian Institution (Stephenson, 1941)
Locality: Castroville Road, Bexar County, Texas (Stephenson, 1941)
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 leonensis Stephenson, 1941
TYPE SPECIES: Spatangus granulosus Goldfuss, 1829
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Navarro (Stephenson, 1941)
Formations: Corsicana Marl (Stephenson, 1941; Cooke, 1953)
Stratigraphic Units: Upper Cretaceous, Maastrichtian (Stephenson, 1941)
Counties: Bexar County (Stephenson, 1941)
DESCRIPTION
TOP: Length, width, height: 16.1 mm × 16.0 mm × 7.8 mm
Top shape: Cordate, with a shallow, rounded frontal notch; upper surface rounded (Cooke, 1953)
Top domed: Slightly higher in front than behind (Cooke, 1953)
SIDE: Truncation: Truncated behind (Cooke, 1953)
BOTTOM: Bottom flat: Oral surface concave (Cooke, 1953)
AMB: Amb shape: Paired petals extending more than halfway to the margin (Cooke, 1953)
Amb primary zones: Anterior poriferous zones straight, narrow; posterior poriferous zones slightly curved forward, much wider (Cooke, 1953)
PORE PAIRS: Shape: Anterior zones pores small and circular; Posterior zones inner pores oval, outer pores elongated (Cooke, 1953)
Density variation: Posterior zones much wider than anterior (Cooke, 1953)
TUBERCLES: Primary tubercles: Tubercles scattered (Cooke, 1953)
Primary Perforated: No
GRANULES: Granules pattern: Fine granulation (Cooke, 1953)
FASCIOLE: Fasciole: Marginal fasciole present (Cooke, 1953)
APICAL SYSTEM: Location: In front of the center (Cooke, 1953)
Shape: Elongated; paired plates arranged in two parallel lines headed by the odd ocular plate (Cooke, 1953)
Genital pores: Four genital plates (Cooke, 1953)
PERIPROCT (ANUS): Shape & Size: Nearly circular; slightly higher than wide (Cooke, 1953)
Location: Terminal; well up on a concave posterior truncation (Cooke, 1953)
PERISTOME (MOUTH): Size: Large (Cooke, 1953)
Shape: Transversely oval (Cooke, 1953)
Location: At the anterior third (Cooke, 1953)
SPECIMENS STUDIED & CONDITION
Specimen condition: Holotype USNM 76279 .
ETYMOLOGY: Named for Leon Creek (Bexar County), which flows near the type locality at Castroville Road (Stephenson, 1941).
REMARKS & COMPARISONS
Remarks: Cardiaster leonensis is described as small for the genus (Cooke, 1953). It was originally described in Stephenson's comprehensive The Larger Invertebrate Fossils of the Navarro Group of Texas (1941).
Comparisons: Compared to Cardiaster hilli (Campanian, Anacacho Fm.), C. leonensis has a more sunken unpaired ambulacrum that is narrower at the top edge. The pore pairs of C. leonensis are much more rounded compared to the elongated pores of C. hilli, and the periproct is nearly circular rather than oval .
