Leptosalenia reidi Thompson, 2020
Plate: LeRe-10
Series: Lower Cretaceous Group: Washita Formation: Weno
Locale: Fort Worth County: Tarrant Stage: Albian
Length: 7.0 mm Height: 3.8 mm
Collector: Robert R. Reid of Fort Worth, Texas.
Holotype NPL 94341
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
HOLOTYPE INFO:
Holotype: NPL 94341 .
Locality: Fort Worth, Tarrant County, Texas.
Stratigraphy: Upper Weno Formation, Washita Group.
SYSTEMATIC PALEONTOLOGY – TAXONOMY
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: LEPTOSALENIA Smith & Wright, 1990
Species: Leptosalenia reidi Thompson, 2020
TYPE SPECIES: Salenia prestensis Desor, 1856
DIAGNOSIS
A tiny Leptosalenia from the Weno Formation distinguished by a depressed, box-like profile. Interambulacra typically feature 2 primary tubercles, 2 adoral secondary tubercles, and 0–1 adapical secondary tubercle.
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Washita
Formations: Weno Formation (Upper).
Stratigraphic Units: Lower Cretaceous, Albian.
Counties: Tarrant.
Abundance: Rare; only one specimen known.
Associated Fauna: Found associated with the starfish fauna Alkaidia sumralli, Capellia mauricei, and Betelgeusia reidi. Associated echinoids include Goniophorus scotti, Goniopygus sp., and Cidarid sp. Also shark teeth, ammonites, gastropods, and pelecypods.
DESCRIPTION
TOP: Length, width, height: 7.0 mm L × 3.8 mm H.
Top shape: Circular outline.
Top domed: Apical system is thick and sits on the corona as a raised cap. Apex is located at the inside lip of the periproct.
SIDE: Ambitus: Positioned 40% of height from the adoral surface.
Side shape: Profile is depressed (height 54% of width) and box-like with steep sides.
BOTTOM: Bottom shape: Diameter is larger than the apical system.
AMB: Amb shape: Two ambulacra are flexuous just under the apical system; three are straight. Widest at the peristome.
Amb arrangement: Ambulacra are approximately half the width of interambulacra (Interambs 2.1x Amb size).
PORE PAIRS: Arrangement: Uniserial.
Elements: Bigeminate; crowded at the peristome.
TUBERCLES: Primary Perforated: No (Imperforate).
Primary Crenulate: Ambulacral tubercles very slightly crenulate.
Ambulacral Tubercles: Two rows of 9 tubercles.
Interambulacral Tubercles: Two rows of 4–5 tubercles (two large, two smaller adorally, and zero or one adapically).
Areolas: Raised; mamelons large and protruding.
Scrobicular Tubercles: Surround each primary tubercle except on the adradial side.
GRANULES: Distribution: Further granulation present along the interradial suture.
FASCIOLE: Absent.
APICAL SYSTEM: Size: Very large; diameter ~75% of test diameter.
Shape: Round.
Plating: Each genital plate has a central gonopore. Ocular plates are tall and "bird-shaped"; outside edges have two rounded bumps on either side.
Ornamentation: Sutural pits vary by plate: 9 pits surround Genitals I, II, and III; 7 pits surround Genitals IV and V. Oculars have 3 sutural pits on the inside edge.
PERIPROCT (ANUS): Shape: Appears subpentagonal.
Features: Surrounded by a lip. Suranal plate is missing in the holotype.
PERISTOME (MOUTH): Size: Large; diameter 56% of test diameter.
Lip: Ten buccal notches; lips invaginated and present on the interambulacral side of notches only.
SPINES: Unknown.
SPECIMENS STUDIED & CONDITION: One specimen studied: Holotype NPL 94341.
ETYMOLOGY
Named after Robert R. Reid, a fossil collector from Fort Worth, Texas, who discovered the holotype.
REMARKS & COMPARISONS
Remarks: The box-like profile of L. reidi resembles that of Salenia elliotti and Salenia stenzeli. However, L. reidi is distinguished by the exceptional thickness of its apical system compared to other Leptosalenia species.
Plate: LeRe-10
Series: Lower Cretaceous Group: Washita Formation: Weno
Locale: Fort Worth County: Tarrant Stage: Albian
Length: 7.0 mm Height: 3.8 mm
Collector: Robert R. Reid of Fort Worth, Texas.
Holotype NPL 94341
Repository: Non-vertebrate Paleo. Lab., Univ. of Texas
HOLOTYPE INFO:
Holotype: NPL 94341 .
Locality: Fort Worth, Tarrant County, Texas.
Stratigraphy: Upper Weno Formation, Washita Group.
SYSTEMATIC PALEONTOLOGY – TAXONOMY
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: LEPTOSALENIA Smith & Wright, 1990
Species: Leptosalenia reidi Thompson, 2020
TYPE SPECIES: Salenia prestensis Desor, 1856
DIAGNOSIS
A tiny Leptosalenia from the Weno Formation distinguished by a depressed, box-like profile. Interambulacra typically feature 2 primary tubercles, 2 adoral secondary tubercles, and 0–1 adapical secondary tubercle.
STRATIGRAPHICAL OCCURRENCE & DISTRIBUTION
Group: Washita
Formations: Weno Formation (Upper).
Stratigraphic Units: Lower Cretaceous, Albian.
Counties: Tarrant.
Abundance: Rare; only one specimen known.
Associated Fauna: Found associated with the starfish fauna Alkaidia sumralli, Capellia mauricei, and Betelgeusia reidi. Associated echinoids include Goniophorus scotti, Goniopygus sp., and Cidarid sp. Also shark teeth, ammonites, gastropods, and pelecypods.
DESCRIPTION
TOP: Length, width, height: 7.0 mm L × 3.8 mm H.
Top shape: Circular outline.
Top domed: Apical system is thick and sits on the corona as a raised cap. Apex is located at the inside lip of the periproct.
SIDE: Ambitus: Positioned 40% of height from the adoral surface.
Side shape: Profile is depressed (height 54% of width) and box-like with steep sides.
BOTTOM: Bottom shape: Diameter is larger than the apical system.
AMB: Amb shape: Two ambulacra are flexuous just under the apical system; three are straight. Widest at the peristome.
Amb arrangement: Ambulacra are approximately half the width of interambulacra (Interambs 2.1x Amb size).
PORE PAIRS: Arrangement: Uniserial.
Elements: Bigeminate; crowded at the peristome.
TUBERCLES: Primary Perforated: No (Imperforate).
Primary Crenulate: Ambulacral tubercles very slightly crenulate.
Ambulacral Tubercles: Two rows of 9 tubercles.
Interambulacral Tubercles: Two rows of 4–5 tubercles (two large, two smaller adorally, and zero or one adapically).
Areolas: Raised; mamelons large and protruding.
Scrobicular Tubercles: Surround each primary tubercle except on the adradial side.
GRANULES: Distribution: Further granulation present along the interradial suture.
FASCIOLE: Absent.
APICAL SYSTEM: Size: Very large; diameter ~75% of test diameter.
Shape: Round.
Plating: Each genital plate has a central gonopore. Ocular plates are tall and "bird-shaped"; outside edges have two rounded bumps on either side.
Ornamentation: Sutural pits vary by plate: 9 pits surround Genitals I, II, and III; 7 pits surround Genitals IV and V. Oculars have 3 sutural pits on the inside edge.
PERIPROCT (ANUS): Shape: Appears subpentagonal.
Features: Surrounded by a lip. Suranal plate is missing in the holotype.
PERISTOME (MOUTH): Size: Large; diameter 56% of test diameter.
Lip: Ten buccal notches; lips invaginated and present on the interambulacral side of notches only.
SPINES: Unknown.
SPECIMENS STUDIED & CONDITION: One specimen studied: Holotype NPL 94341.
ETYMOLOGY
Named after Robert R. Reid, a fossil collector from Fort Worth, Texas, who discovered the holotype.
REMARKS & COMPARISONS
Remarks: The box-like profile of L. reidi resembles that of Salenia elliotti and Salenia stenzeli. However, L. reidi is distinguished by the exceptional thickness of its apical system compared to other Leptosalenia species.
