Eupatagus carolinensis Clark, 1915
Plate: EuCa-10
Series: Eocene Group: Middle Claiborne Formation: Cook Mountain
Locale: Little Brazos River County: Brazos Stage: Lutetian
Length: 39.0 mm Width: 62.3 mm Height: 20.8 mm
Specimen in photo: TX 2004.1 (Fragment)
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
HOLOTYPE INFO:
Holotype: USNM 164669 (originally described as Johns Hopkins University T. 2004) — National Museum of Natural History, Smithsonian Institution (Clark & Twitchell, 1915; Cooke, 1959)
Locality: Wilmington, New Hanover County, North Carolina (Clark & Twitchell, 1915)
SYSTEMATIC PALEONTOLOGY – TAXONOMY
Class: Echinoidea Leske, 1778
Subclass: Euechinoidea Bronn, 1860
Infraclass: Irregularia Latreille, 1825
Superorder: Atelostomata Zittel, 1879
Order: Spatangoida L. Agassiz, 1840
Family: Brissidae Gray, 1855
Genus: EUPATAGUS L. Agassiz, 1847
Species: Eupatagus carolinensis Clark, 1915
TYPE SPECIES: Eupatagus valenciennesii L. Agassiz, 1847
DIAGNOSIS
Test oval, moderately tumid, with a slight posterior keel. Ambulacra depressed; anterolateral pair shorter than posterolateral. Large tubercles confined to the paired interambulacra within the peripetalous fasciole. Peristome large, semilunar; periproct submarginal (Clark & Twitchell, 1915; Cooke, 1942).
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Middle Claiborne (Texas)
Formations: Cook Mountain Formation (Texas); Castle Hayne Limestone (North Carolina) (Clark & Twitchell, 1915; Cooke, 1942)
Stratigraphic Units: Middle Eocene, Lutetian (Texas); Middle/Late Eocene (North Carolina)
Counties: Brazos County (Texas); New Hanover County (North Carolina)
DESCRIPTION
TOP: Length, width, height: 39.0 mm L × 62.3 mm W × 20.8 mm H (Specimen TX 2004.1 is a fragment; dimensions represent incomplete test)
Top shape: Oval, narrowly truncated behind (Cooke, 1942); Posterior margin slightly contracted (Clark & Twitchell, 1915)
Top domed: Moderately inflated/tumid; nearly flat along the median line (Clark & Twitchell, 1915)
SIDE: Side shape: Steeply sloping in front (Cooke, 1942)
Keel: Slight posterior keel present (Clark & Twitchell, 1915)
BOTTOM: Bottom shape: Nearly flat to gently convex (Clark & Twitchell, 1915; Cooke, 1942)
AMB: Amb shape: Anterior ambulacrum flattened/weakly depressed, not petaloid. Paired ambulacra broad, occupying shallow grooves (Clark & Twitchell, 1915; Cooke, 1942)
Amb arrangement: Petals long, slightly sunken, straight, narrowly lanceolate, nearly closed (Cooke, 1942)
Dimensions: Posterolateral petals longer than anterolateral petals (Clark & Twitchell, 1915). Anterior pair diverging at 132°; posterior pair at 38° (Cooke, 1942).
Amb primary zones: Anterior poriferous zone of anterior pair narrowing near the apex (Cooke, 1942)
PORE PAIRS: Shape: Oval (Cooke, 1942); Rather large (Clark & Twitchell, 1915)
Conjugate vs Nonconjugate: Strongly conjugate; connected by furrows (Cooke, 1942; Clark & Twitchell, 1915)
TUBERCLES: Primary tubercles: Large tubercles confined to the paired interambulacra within the peripetalous fasciole (Cooke, 1942). Tubercles on lower surface much larger than on upper surface (Clark & Twitchell, 1915).
FASCIOLE: Peripetalous fasciole oval, narrow, clearly defined. Subanal fasciole narrow below, broader above (probably heart-shaped) (Cooke, 1942; Clark & Twitchell, 1915).
Anal fasciole: Right-hand branch of an anal fasciole visible on some specimens (Cooke, 1942).
APICAL SYSTEM: Location: Excentric, well forward (behind anterior third) (Clark & Twitchell, 1915; Cooke, 1942)
Size: Small (Clark & Twitchell, 1915)
Genital pores: Four genital pores (Cooke, 1942)
Type: Ethmolytic; madreporite moderately extended (Cooke, 1942)
PERIPROCT (ANUS): Shape & Size: Oval; higher than wide (Cooke, 1942)
Visibility: Barely visible from above (Cooke, 1942)
PERISTOME (MOUTH): Shape: Semilunar (Clark & Twitchell, 1915); Suboval (Cooke, 1942)
Location: Excentric in front (at anterior third) (Clark & Twitchell, 1915; Cooke, 1942)
SPECIMENS STUDIED & CONDITION: Specimen TX 2004.1 is a fragment. Dimensions provided: 39 mm x 62.3 mm .
ETYMOLOGY: Named for North Carolina, the origin of the holotype.
REMARKS & COMPARISONS
Remarks: The structure of the lower surface is similar to Eupatagus antillarum and E. ocalanus, placing it in the same subgenus despite the presence of an anal fasciole. It differs from Plagiobrissus by having a long narrow labrum (Cooke, 1942).
Note: A second specimen is noted from "Erizos Fosiles."
Plate: EuCa-10
Series: Eocene Group: Middle Claiborne Formation: Cook Mountain
Locale: Little Brazos River County: Brazos Stage: Lutetian
Length: 39.0 mm Width: 62.3 mm Height: 20.8 mm
Specimen in photo: TX 2004.1 (Fragment)
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
HOLOTYPE INFO:
Holotype: USNM 164669 (originally described as Johns Hopkins University T. 2004) — National Museum of Natural History, Smithsonian Institution (Clark & Twitchell, 1915; Cooke, 1959)
Locality: Wilmington, New Hanover County, North Carolina (Clark & Twitchell, 1915)
SYSTEMATIC PALEONTOLOGY – TAXONOMY
Class: Echinoidea Leske, 1778
Subclass: Euechinoidea Bronn, 1860
Infraclass: Irregularia Latreille, 1825
Superorder: Atelostomata Zittel, 1879
Order: Spatangoida L. Agassiz, 1840
Family: Brissidae Gray, 1855
Genus: EUPATAGUS L. Agassiz, 1847
Species: Eupatagus carolinensis Clark, 1915
TYPE SPECIES: Eupatagus valenciennesii L. Agassiz, 1847
DIAGNOSIS
Test oval, moderately tumid, with a slight posterior keel. Ambulacra depressed; anterolateral pair shorter than posterolateral. Large tubercles confined to the paired interambulacra within the peripetalous fasciole. Peristome large, semilunar; periproct submarginal (Clark & Twitchell, 1915; Cooke, 1942).
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Middle Claiborne (Texas)
Formations: Cook Mountain Formation (Texas); Castle Hayne Limestone (North Carolina) (Clark & Twitchell, 1915; Cooke, 1942)
Stratigraphic Units: Middle Eocene, Lutetian (Texas); Middle/Late Eocene (North Carolina)
Counties: Brazos County (Texas); New Hanover County (North Carolina)
DESCRIPTION
TOP: Length, width, height: 39.0 mm L × 62.3 mm W × 20.8 mm H (Specimen TX 2004.1 is a fragment; dimensions represent incomplete test)
Top shape: Oval, narrowly truncated behind (Cooke, 1942); Posterior margin slightly contracted (Clark & Twitchell, 1915)
Top domed: Moderately inflated/tumid; nearly flat along the median line (Clark & Twitchell, 1915)
SIDE: Side shape: Steeply sloping in front (Cooke, 1942)
Keel: Slight posterior keel present (Clark & Twitchell, 1915)
BOTTOM: Bottom shape: Nearly flat to gently convex (Clark & Twitchell, 1915; Cooke, 1942)
AMB: Amb shape: Anterior ambulacrum flattened/weakly depressed, not petaloid. Paired ambulacra broad, occupying shallow grooves (Clark & Twitchell, 1915; Cooke, 1942)
Amb arrangement: Petals long, slightly sunken, straight, narrowly lanceolate, nearly closed (Cooke, 1942)
Dimensions: Posterolateral petals longer than anterolateral petals (Clark & Twitchell, 1915). Anterior pair diverging at 132°; posterior pair at 38° (Cooke, 1942).
Amb primary zones: Anterior poriferous zone of anterior pair narrowing near the apex (Cooke, 1942)
PORE PAIRS: Shape: Oval (Cooke, 1942); Rather large (Clark & Twitchell, 1915)
Conjugate vs Nonconjugate: Strongly conjugate; connected by furrows (Cooke, 1942; Clark & Twitchell, 1915)
TUBERCLES: Primary tubercles: Large tubercles confined to the paired interambulacra within the peripetalous fasciole (Cooke, 1942). Tubercles on lower surface much larger than on upper surface (Clark & Twitchell, 1915).
FASCIOLE: Peripetalous fasciole oval, narrow, clearly defined. Subanal fasciole narrow below, broader above (probably heart-shaped) (Cooke, 1942; Clark & Twitchell, 1915).
Anal fasciole: Right-hand branch of an anal fasciole visible on some specimens (Cooke, 1942).
APICAL SYSTEM: Location: Excentric, well forward (behind anterior third) (Clark & Twitchell, 1915; Cooke, 1942)
Size: Small (Clark & Twitchell, 1915)
Genital pores: Four genital pores (Cooke, 1942)
Type: Ethmolytic; madreporite moderately extended (Cooke, 1942)
PERIPROCT (ANUS): Shape & Size: Oval; higher than wide (Cooke, 1942)
Visibility: Barely visible from above (Cooke, 1942)
PERISTOME (MOUTH): Shape: Semilunar (Clark & Twitchell, 1915); Suboval (Cooke, 1942)
Location: Excentric in front (at anterior third) (Clark & Twitchell, 1915; Cooke, 1942)
SPECIMENS STUDIED & CONDITION: Specimen TX 2004.1 is a fragment. Dimensions provided: 39 mm x 62.3 mm .
ETYMOLOGY: Named for North Carolina, the origin of the holotype.
REMARKS & COMPARISONS
Remarks: The structure of the lower surface is similar to Eupatagus antillarum and E. ocalanus, placing it in the same subgenus despite the presence of an anal fasciole. It differs from Plagiobrissus by having a long narrow labrum (Cooke, 1942).
Note: A second specimen is noted from "Erizos Fosiles."
