Henderson and Daniels (1917) commented that Yarrow's (1875) and Ingersoll's (1876) Utah records of Valvata sincera probably should be referred to Valvata humeralis. According to Taylor (1986), Russell (1971) misidentified this species as Valvata utahensis.
The subspecies found in Utah is Valvata humeralis californica.
Status in Utah
At least 12 Utah occurrences of this species have been reported in the literature. All reported localities for this species in Utah are from the central and western parts of the state. Chamberlin and Jones (1929) documented this species in Kane, Sevier, Utah, Wasatch, Rich, and Box Elder counties. Jones (1940a) provided an additional locality in Utah County. Woolstenhulme (1942a) reported material from Tooele County. The only recent report of the species in Utah is from Fish Springs National Wildlife Refuge in Juab County (Taylor 1986).
Although some authors (e.g., Chamberlin and Jones 1929) have listed records of this species from Salt Lake County, most or all of these records are very old (Yarrow 1875, Ingersoll 1876) and were assigned in the original sources to another species, Valvata sincera, now considered to occur only in northeastern North America. Although these early records probably do apply to Valvata humeralis as Henderson and Daniels (1917) opined and Valvata humeralis probably did formerly inhabit Salt Lake County, this has not been persuasively demonstrated and must be regarded as speculative.
Chamberlin and Jones (1929) noted that this species was "plentiful" at Fish Lake, Sevier County. Jones (1940a) listed Utah collections of 5, 5, and "several", and, although he did not indicate whether any of these had been collected live, he seemingly was distinguishing these from fossil or subfossil material. Woolstenhulme (1942a, 1942b) also reported 2 Utah collections of "several". Taylor (1986) found 440 live individuals and numerous empty shells of this species at one locality.
Threats to this species in Utah almost certainly include alterations and elimination of aquatic habitat. Introductions of aquatic organisms such as fishes and other species of mollusks may also represent threats to this species. Population trend in Utah is not known.
Sites of all known historical occurrences of this species in Utah should be revisited in order to determine its current status in the state.
Habitats Utilized in Utah
This species has been found in ditches, spring outflows, and spring source pools at Fish Springs National Wildlife Management Area (Taylor 1986). It has also been reported in Utah from several lakes and a reservoir (Chamberlin and Jones 1929, Chamberlin and Berry 1930).