Stromboidea
Original Diagnosis of Tessarolax bullardi by Saul & Squires, 2015:
- ”Mature last whorl bicarinate, anterior carina forming low crest of slightly elevated nodes in dorsal area; callus generally thin; fictavarix short, flange-shaped, and extending ventrally to form short stabilizer.”
Original Description of Tessarolax bullardi by Saul & Squires, 2015:
- "Shell up to 113 mm high and 60 mm wide almost complete). Protoconch unknown. Teleoconch at least five whorls (tip missing). Suture and immature shell callused over. Immature shell: Turriculate, consisting of four whorls, early spire whorls unicarinate and finely ribbed. Mature shell: Consisting of last whorl, bicarinate, with carinae noded and parallel. Single midrib present between carinae dying out about at mid-dorsum. Posterior carina with lower, more discrete nodes. Anterior carina with coalescent stronger nodes, which near center of dorsum are slightly to moderately elevated and form low crest with four or five prominent nodes. Aperture moderately narrow. Outer lip thick, expanded into four canaliculate digitations. Apical digitation slightly curved, extending along spire but diverging away from tip of shell. Posterior and anterior outer lip digitations long, strongly curved, and extending from their respective carinae. Anterior outer lip ventrally bearing callus knob. Rostral digitation long and slightly curved. Callus covering shell, obscuring ornamentation except for carinae on last whorl. Callus on venter forms flat, thin surface with sharp edges. Ablabral-callus process flange-shaped; more set off from ventral surface on younger specimens than onmore adult ones, on which ablabral callus merges somewhat with ventral callus. Fictavarix extending ventrally to form short stabilizer."
Locus typicus: Downstream end of high-siltstone exposure along bank of Chemainus River,near Chemainus, Nanaimo, Vancouver Island, British Columbia Province, Canada
Stratum typicum: lower Haslam Formation, upper Santonian, upper Cretaceous
Geographic Range: Vancouver Island, British Columbia Province, Canada to southern California., USA.
Etymology: The species is named for Timon Bullard, who collected and prepared many of the specimens.
Tessarolax bullardi Saul & Squires, 2015; Holotype; lower Haslam Formation, upper Santonian, upper Cretaceous; Downstream end of high-siltstone exposure along bank of Chemainus River, near Chemainus, Nanaimo, Vancouver Island, British Columbia, Canada; Coll. no. RBCM.EH2011.007.0002; Copyright Natural History Museum of Los Angeles County.
Tessarolax bullardi Saul & Squires, 2015
- Left: Paratype; lower Haslam Formation, upper Santonian, upper Cretaceous; Downstream end of high-siltstone exposure along bank of Chemainus River, south and west of town of Chemainus, Nanaimo, east coast of Vancouver Island, British Columbia Province, Canada; Coll. no. RBCM.EH2011.007.003
- Right: Paratype; lower Haslam Formation, upper Santonian, upper Cretaceous; Siltstone on northern bank of Puntledge River at the Van Arcs Farm, near Courtenay, Vancouver Island, British Columbia Province, Canada; Coll. no. RBCM.EH2011.007.004
- Copyright Natural History Museum of Los Angeles County.
Tessarolax bullardi Saul & Squires, 2015; Paratype; lower Haslam Formation, upper Santonian, upper Cretaceous; Siltstone on northern bank of Puntledge River at the Van Arcs Farm, near Courtenay, Vancouver Island, British Columbia Province, Canada; Coll. no. RBCM.EH2011.007.005; Copyright Natural History Museum of Los Angeles County.
Tessarolax bullardi Saul & Squires, 2015
- Left: Paratype; lower Haslam Formation, upper Santonian, upper Cretaceous; Downstream end of high-siltstone exposure along bank of Chemainus River, south and west of town of Chemainus, Nanaimo, east coast of Vancouver Island, British Columbia Province, Canada; Coll. no. RBCM.EH2011.007.006
- Right: Paratype; lower Haslam Formation, upper Santonian, upper Cretaceous; Siltstone on northern bank of Puntledge River at the Van Arcs Farm, near Courtenay, Vancouver Island, British Columbia Province, Canada; Coll. no. RBCM.EH2011.007.004
- Copyright Natural History Museum of Los Angeles County.
References:
