Species: alexandrae MERRIAM, 1904
Etymology:
Holotype: UCMP 9085
Locality: UCMP locality 1013, Bear Cove, Sec. 34, T35N, R2W, Lying between Squaw Creek and Pitt River, northern part of Shasta County, California.
Horizon: Hosselkus Limestone.
Biostratigraphy:
Age: Carnian Stage, Lower Late Triassic Epoch, Late Triassic.
Material: Skull missing posterior end, right quadrate, cervical, dorsal and caudal vertebrae, coracoid, scapula, humerus, ulna, radius, ischium, and ribs.
Referred material:
UCMP 9084: Posterior part of skull and mandible, vertebrae, pubis? humerus and radius.
HILTON, 2003
UCMP 10815: Teeth.
UCMP 9045: Pubis.
UCMP 9044: Pubis?
UCMP 9121: Mandible with teeth.
UCMP 39226: Right upper mandible and lower mandible.
UCMP 10628: Teeth.
UCMP 9123: Posterior premaxilla.
UCMP 11228: Mandible with teeth.
UCMP 39266: Skull.
NICHOLLS, 1999
USNM 10926: Incomplete skull and mandible, lacking region anterior to naris.
UCMP 9122: Isolated vomer,
UCMP 9126: Quadrate.
UCMP 8123: Premaxilla.
= Thalattosaurus perrini (MERRIAM 1905)
Locality: Smith Cove, near Squaw Creek, northern part of Shasta County, California.
Horizon: Hosselkus Limestone.
Biostratigraphy:
Age: Carnian Stage, Lower Late Triassic Epoch, Late Triassic.
Material:
CAS 66236.01: Vomer.
Note: Not type.
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Species: perrini MERRIAM, 1905 (nomen nudum)
= Scenodon perrini (MERRIAM, 1905) MERRIAM, 1905
Etymology:
Note: In the same Thalattosaurus perrini is named, in a foot note Merriam wrote…Should this type be found to be genetically distinct from Thalattosaurus the generic name Scenodon will be used to distinguish
Holotype: Unknown, and lost.
Locality: Smith Cove, near Squaw Creek, northern part of Shasta County, California.
Horizon: Hosselkus Limestone.
Biostratigraphy:
Age: Carnian Stage, Lower Late Triassic Epoch, Late Triassic.
Material: Dentary, maxilla, prefrontal, frontal, palatine, splenial, articular, supra-angular, angular, teeth, prevomer, and rib.
Referred material:
NICHOLLS, 1999
UCMP 10620: A small dentary.
= Paralonetes sp NICHOLLS & BRINKMAN, 1993 (as per NICHOLLS, 1999)
Locality: "T" crique, near Wapiti Lake, 54'31"10'"N, 120'43"19'"W, British Columbia Province, Canada.
Horizon: Sulphur Mountain Formation.
Biostratigraphy:
Age: Griesbachian to Spathian in Stage, Upper Scythian Epoch, Late Early Triassic.
Material:
RTMP 89.126.2: Disarticulated elements including maxilla, premaxilla, jugal, incomplete pterygoid, dentary, prootic, unidentified elements and isolated vertebrae and ribs.
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Species: borealis NICHOLLS & BRINKMAN, 1993
Etymology: Latin, borealis, "northern."
Holotype: RTMP. 89.126.1
Locality: South west side of "T" crique, near Wapiti Lake, 54'30"44'"N, 120'42"22'"W, British Columbia Province, Canada.
Horizon: Sulphur Mountain Formation.
Biostratigraphy:
Age: Griesbachian to Spathian in Stage, Upper Scythian Epoch, Late Early Triassic.
Material: Anterior part of skull, from tip of snout to orbital region, preserved
in right lateral view, and incomplete mandible, left pterygoid, and isolated
ribs and centra.