Oreohelix handi
Pilsbry and Ferriss, 1918
Spring Mountainsnail
G1Critically ImperiledGlobal Rank
HighThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.110415
Element CodeIMGASB5130
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryInvertebrate Animal
Endemicendemic to a single nation
KingdomAnimalia
PhylumMollusca
ClassGastropoda
OrderStylommatophora
FamilyOreohelicidae
GenusOreohelix
Concept ReferenceTurgeon, D. D., J. F. Quinn, Jr., A. E. Bogan, E. V. Coan, F. G. Hochberg, W. G. Lyons, P. M. Mikkelsen, R. J. Neves, C. F. E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F. G. Thompson, M. Vecchione, and J. D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland. 526 pp.
Conservation Status
Rank MethodLegacy Rank calculation - Biotics v1
Review Date2019-09-25
Change Date2002-10-08
Edition Date2019-09-25
Edition AuthorsMiskow, E. NDNH
Threat ImpactHigh
Range Extent<100 square km (less than about 40 square miles)
Number of Occurrences6 - 20
Rank ReasonsSurveys (2006, 2010, and 2011) and data indicate that Oreohelix handi are uncommon and possibly declining in Kyle Canyon and adjacent canyons in the Spring Mountains. Current and on-going development from summer homes and parking lots has diminished much of the historical habitat.
Range Extent CommentsThis species is endemic to Nevada, U.S. It is known from the eastern slopes of the Spring Mountains along the northeastern slopes of Mt. Charleston and two outlier populations in the Deer Creek Drainage representing about 11.5 square kilometers.
Occurrences CommentsTen populations have been documented since 1918, however post-2000 surveys have recorded only 8 current extant locations.
Threat Impact CommentsPotential negative impacts are habitat loss of talus slopes and vegetation due to development of summer homes and increased roads and trails in the area. In addition, human caused wildfires have contributed to loss of habitat.
Ecology & Habitat
Description
Considered a distinct species, co-occurs with O. hemphilli in Spring Mountains. Genetic work in 2009 show that there is a phylogenetic relationship between O. handi and O. hemphilli. In addition, shell size, genitalia differences and habitat preferences separate the two taxa. Mean diameter and height of O. handi from recent specimens are 8.17 mm and 4.51 mm respectively.
Diagnostic Characteristics
The mean diameter and height of Oreohelix handi are 8.17 and 4.51 mm respectively, based on 16 shells.
Habitat
The Spring Mountain snail can be considered an exceptionally high elevation species for this genus. High quality habitats include, north facing slopes, with 60-80 % cover by deciduous trees and shrubs with good to excellent talus/litter matrix of greater than 10 cm deep, cool to damp soil.
Ecology
Mountain snails are highly adapted to changing seasons of montane environments. The Spring Mountain snail can be considered an exceptionally high elevation species for this genus.
Reproduction
Colonies are primarily active in mid-June, least active to absent in late May and late September. This species hibernates during winter and aestivates in the late summer. O. handi is hermaphroditic, giving birth to 3-8 live young in early spring. The majority lay eggs in soil. Snails typically live 3 to 5 years.
Terrestrial HabitatsWoodland - MixedShrubland/chaparralBare rock/talus/scree
Other Nations (1)
United StatesN1
| Province | Rank | Native |
|---|
| Nevada | S1 | Yes |
| California | SNR | Yes |
References (2)
- Ports, M. 2011. Evaluation Report, Species Accounts and Surveys for Oreohelix in Spring Mountains. Internal Report. 21p.
- Turgeon, D. D., J. F. Quinn, Jr., A. E. Bogan, E. V. Coan, F. G. Hochberg, W. G. Lyons, P. M. Mikkelsen, R. J. Neves, C. F. E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F. G. Thompson, M. Vecchione, and J. D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland. 526 pp.