Bathysalenia skylari Jagt, Jackson & van der Ham, 2014
Plate: BaSk-10
Series: Upper Cretaceous Group: Eagle Ford Formation: Eagle Ford Condensed Zone
Locale: Georgetown County: Williamson Stage: Late Turonian
Length: 7.4 mm Height: 3.5 mm
Specimen in photo: NPL 63876
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
Plate: BaSk-20
Series: Upper Cretaceous Group: Eagle Ford Formation: Lower Boquillas
Locale: Big Lozier Canyon County: Terrell Stage: Late Turonian
Length: 6.9 mm Height: 2.6 mm
Collector: Kevin Durney
Repository: Private Collection
HOLOTYPE INFO:
Holotype: NPL 63876 — Non-vertebrate Paleontology Laboratory, University of Texas (Jagt et al., 2014)
Locality: Georgetown area, Williamson County, Texas (Jagt et al., 2014)
Original Horizon: Eagle Ford Condensed Zone, Prionocyclus hyatti cephalopod Zone (Jagt et al., 2014)
Systematic Paleontology
CLASS: ECHINOIDEA Leske, 1778
SUBCLASS: EUECHINOIDEA Bronn, 1860
INFRACLASS: CARINACEA Kroh & Smith, 2010
SUPERORDER: CALYCINA Gregory, 1900
ORDER: SALENIOIDA Delage & Hérouard, 1903
FAMILY: SALENIIDAE L. Agassiz, 1838
GENUS: BATHYSALENIA Pomel, 1883
SPECIES: Bathysalenia skylari Jagt, Jackson & van der Ham, 2014
TYPE SPECIES: Salenia tertiaria Tate, 1877
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Eagle Ford (Jagt et al., 2014)
Formations: Eagle Ford Condensed Zone (Jagt et al., 2014), Boquillas Formation
Stratigraphic Units: Upper Cretaceous, Late Turonian (Jagt et al., 2014)
Counties: Williamson County, Terrell County
DESCRIPTION
TOP: Length, height: 7.4 mm × 3.5 mm
Top shape: Circular aborally; test small
Flatness: Apical disc sits very flush with top
SIDE: Ambitus: Very low ambitus
Side shape: Sides rise to low ambitus, then curve more pronouncedly toward top
BOTTOM: Bottom flat: Very flat
AMB: Amb shape: Wide, straight; width constant from apical plate to peristome, then narrows slightly
Amb primary tubercles: Each pore pair has a tubercle between them; two additional rows of tubercles run up the center, alternating in size
Amb arrangement: Bigeminate plates (Jagt et al., 2014; Generic Definition)
INTERAMB: Interamb size: 1.5 times larger than ambs
Interamb plating: Six large, 6-sided plates per column, each with a primary tubercle; plates staggered
PORE PAIRS: Shape: Round
SUTURES: Primary Perforated: No (Jagt et al., 2014)
Primary Crenulate: Yes—pronouncedly crenulate
Primary Mamelon: Mamelated
TUBERCLES: Primary tubercles: Mamelated, imperforate, crenulate
Secondary tubercles: Scrobicular tubercles line margin of plates; sparse granulation on large plates
APICAL SYSTEM: Size: Very large; diameter about 70% of test diameter
Ornamentation: Plates crowded with short pointed bumps over entire surface; some bumps fused forming occasional ridges
Relief: Sits flush with top
PERIPROCT (ANUS): Size: About 1/4 size of apical disc
Ornamentation: Bumps line edge of periproct
PERISTOME (MOUTH): Size: Very large, making up about 50% of the bottom
Shape: Depressed
Lip: Notches very pronounced; large lips extend across entire interambs
SPECIMENS STUDIED & CONDITION:
Specimen condition: Holotype NPL 63876. Two specimens from Kevin Durney.
SPINES: Small spines are needle like. Large spines lanceolate, large collars, longitudinal ridges run the entire length of the spines – above and below the collars.
SIZE:
Remarks: Bathysalenia skylari represents the first record of the genus Bathysalenia from North America (Jagt et al., 2014). It was named in honor of Skylar Jackson.
Comparisons: The species is characterized by its very large apical system (~70% of test diameter) and intense apical ornamentation.
Stratigraphic Note: The original description by Jagt et al. (2014) places the holotype in the "Eagle Ford Condensed Zone" of Late Turonian age (Prionocyclus hyatti zone). The specimen likely originates from the contact boundary between the Eagle Ford and Austin groups.
Remarks: (02-2026) Two specimens (6.9 and 6.3 mm) were found by Kevin Durney in the Boquillas formation in Terrel County. The Lower Boquillas Formation (specifically the Ernst Member) in West Texas is the direct time-equivalent of the Eagle Ford Group in Central Texas.
Plate: BaSk-10
Series: Upper Cretaceous Group: Eagle Ford Formation: Eagle Ford Condensed Zone
Locale: Georgetown County: Williamson Stage: Late Turonian
Length: 7.4 mm Height: 3.5 mm
Specimen in photo: NPL 63876
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
Plate: BaSk-20
Series: Upper Cretaceous Group: Eagle Ford Formation: Lower Boquillas
Locale: Big Lozier Canyon County: Terrell Stage: Late Turonian
Length: 6.9 mm Height: 2.6 mm
Collector: Kevin Durney
Repository: Private Collection
HOLOTYPE INFO:
Holotype: NPL 63876 — Non-vertebrate Paleontology Laboratory, University of Texas (Jagt et al., 2014)
Locality: Georgetown area, Williamson County, Texas (Jagt et al., 2014)
Original Horizon: Eagle Ford Condensed Zone, Prionocyclus hyatti cephalopod Zone (Jagt et al., 2014)
Systematic Paleontology
CLASS: ECHINOIDEA Leske, 1778
SUBCLASS: EUECHINOIDEA Bronn, 1860
INFRACLASS: CARINACEA Kroh & Smith, 2010
SUPERORDER: CALYCINA Gregory, 1900
ORDER: SALENIOIDA Delage & Hérouard, 1903
FAMILY: SALENIIDAE L. Agassiz, 1838
GENUS: BATHYSALENIA Pomel, 1883
SPECIES: Bathysalenia skylari Jagt, Jackson & van der Ham, 2014
TYPE SPECIES: Salenia tertiaria Tate, 1877
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Eagle Ford (Jagt et al., 2014)
Formations: Eagle Ford Condensed Zone (Jagt et al., 2014), Boquillas Formation
Stratigraphic Units: Upper Cretaceous, Late Turonian (Jagt et al., 2014)
Counties: Williamson County, Terrell County
DESCRIPTION
TOP: Length, height: 7.4 mm × 3.5 mm
Top shape: Circular aborally; test small
Flatness: Apical disc sits very flush with top
SIDE: Ambitus: Very low ambitus
Side shape: Sides rise to low ambitus, then curve more pronouncedly toward top
BOTTOM: Bottom flat: Very flat
AMB: Amb shape: Wide, straight; width constant from apical plate to peristome, then narrows slightly
Amb primary tubercles: Each pore pair has a tubercle between them; two additional rows of tubercles run up the center, alternating in size
Amb arrangement: Bigeminate plates (Jagt et al., 2014; Generic Definition)
INTERAMB: Interamb size: 1.5 times larger than ambs
Interamb plating: Six large, 6-sided plates per column, each with a primary tubercle; plates staggered
PORE PAIRS: Shape: Round
SUTURES: Primary Perforated: No (Jagt et al., 2014)
Primary Crenulate: Yes—pronouncedly crenulate
Primary Mamelon: Mamelated
TUBERCLES: Primary tubercles: Mamelated, imperforate, crenulate
Secondary tubercles: Scrobicular tubercles line margin of plates; sparse granulation on large plates
APICAL SYSTEM: Size: Very large; diameter about 70% of test diameter
Ornamentation: Plates crowded with short pointed bumps over entire surface; some bumps fused forming occasional ridges
Relief: Sits flush with top
PERIPROCT (ANUS): Size: About 1/4 size of apical disc
Ornamentation: Bumps line edge of periproct
PERISTOME (MOUTH): Size: Very large, making up about 50% of the bottom
Shape: Depressed
Lip: Notches very pronounced; large lips extend across entire interambs
SPECIMENS STUDIED & CONDITION:
Specimen condition: Holotype NPL 63876. Two specimens from Kevin Durney.
SPINES: Small spines are needle like. Large spines lanceolate, large collars, longitudinal ridges run the entire length of the spines – above and below the collars.
SIZE:
- Holotype Size: Diameter 11.1 mm (Jagt et al., 2014).
- Size Range: Diameter 4.8 mm to 12.3 mm (Jagt et al., 2014).
- Average Size: Diameter ~9 mm.
- Largest Known: Diameter 12.3 mm (Jagt et al., 2014)
Remarks: Bathysalenia skylari represents the first record of the genus Bathysalenia from North America (Jagt et al., 2014). It was named in honor of Skylar Jackson.
Comparisons: The species is characterized by its very large apical system (~70% of test diameter) and intense apical ornamentation.
Stratigraphic Note: The original description by Jagt et al. (2014) places the holotype in the "Eagle Ford Condensed Zone" of Late Turonian age (Prionocyclus hyatti zone). The specimen likely originates from the contact boundary between the Eagle Ford and Austin groups.
Remarks: (02-2026) Two specimens (6.9 and 6.3 mm) were found by Kevin Durney in the Boquillas formation in Terrel County. The Lower Boquillas Formation (specifically the Ernst Member) in West Texas is the direct time-equivalent of the Eagle Ford Group in Central Texas.
