Page 57 - Land Snails of New Mexico

Dripping Spring area on the western flank of the Organ Mountains. This subspecies m a y deserve specific status (Dr. William L. Pratt, pers, comm.). Pending publication of Dr. Pratt'sstudies,herewe employ thename minuscula.
General Distribution--This minute snail is widespread, occurring from Alaska and Canada in North America south to Costa Rica in Central America. Ithas been introduced widely e l s e w h e r e , a n d it w a s f r o m s u c h a n i n t r o d u c e d p o p u l a t i o n i n H a w a i i that the generic n a m e w a s derived.
NewMexicoDistributionandHabitat--Astreatedhere, Hawaiia minuscula is a common snail in New Mexico, widespread both geographically and altitudinally. Its broad
altitudinal range lends credence to the possibility (suggested above)thattwospeciesmay bepresentinthestate.Itisfound along the Rio Grande and Pecos River Valleys in cottonwood groves and urban lawns and parks. In mountains, itextends from the Upper Sonoran Zone as high as the Canadian Life Zone, althoughitismostcommon intheTransitionZone. Itoccurs consistently, but in low numbers, in collections of leaf litter taken in montane habitats.
Genus Zonitoides
Zonitoides arboreus (T. Say, 1816, as Helix). (Nicholson's) American Edition, British Encyclopedia Vol. 2,Art.Conchology,speciesNo.2,Pl.4,Fig.4.No precise T.L. (quick gloss)
specimens are found usually in association with low vegetation NorthAmerica.ItextendsacrosssouthernCanadafromBritish suchassedgesandgrasses,indampmontanemeadows,and
General Distribution--This is a widespread species in
Columbia to Newfoundland, and southward across the conterminous United States and México to Central America.
New Mexico Distribution and Habitat--Zonitoides
arboreusiswidespreadinNew Mexico.Asthenamearboreus suggests, it is associated with trees, and is found in most of the state's forested mountains. It is especially typical of the Transition and Canadian Life Zones, and collections of leaf litter from these zones usually contain shells of the species. In some areas where other species are scarce, as in the mountains surroundingtheSanAgustinPlains,Z arboreusmaybetheonly speciesfoundatacollectionsite.On theotherhand,thereisa puzzling absence of Z. arboreus in the San Andres and Organ Mountains (Metcalf, 1984b), although Transition Zone habitat is present in parts of these mountains. However, the species is c o m m o n in the Sierra B l a n c a - S a c r a m e n t o M o u n t a i n s c o m p l e x just across the Tularosa Basin to the east. Zonitoides arboreus alsohasbecomeestablishedin someurbanareas.Itisfoundas a Pleistocene fossil along the Rio Grande and Pecos River valleys,indicatingitwas more widespread atlower elevationsin
along streams and other bodies of water.
FamilyLimacidae Genus Deroceras
ThenativeslugsofNew Mexicocompriseonlytwospecies, both in the genus Deroceras. In addition, there are some introduced Eurasian species of limacid slugs that occur in urban areas,discussedinalatersection.
Deroceraslaeve(O.F.Müller,1774,asLimax). Vermium etc. (see Cionella lubrica for full citation), 2:2. T.L.: Fridrichsdal,Denmark. (meadow slug)
Deroceras laeve is a Holarctic species found throughout muchofNorthAmerica,occurringwidelyinNewMexico.At lower elevations, itis found in cultivated and urban areas and in m a r s h y a r e a s o f r i v e r f l o o d p l a i n s . I n m o u n t a i n s , it o c c u r s m a i n l y around springs and along streams and other bodies of water. It is especially typical of wet montane meadows, sharing this habitat with Vitrina p. alaskana, discussed above.
Deroceras heterura Pilsbry, 1944. The Nautilus, 58:15. T.L.: west side of north summit of Sawyer Peak, Black Range,GrantCo.,New Mexico.(marshslug)
Pilsbry (1948:562) deemed populations of Deroceras from the higher elevations of the Mogollon Mountains and the Black
the past than at present.
Genus Striatura
-
Striatura meridionalis (H. A. Pilsbry and J. H. Ferriss, 1906,asVitrea).ProceedingsoftheAcademyofNatural Sciences of Philadelphia, 58:152. T.L.: drift of Guadalupe River above N e w Braunfels, Comal Co., Texas. (median striate)
As the specific name meridionalis suggests, this is a southern species in the United States, occurring from the southeastern to the southwestern states and southward into
México. InNewMexico,thisspeciesisfoundinforested habitats throughout the Transition and Canadian Life Zones.
Family Vitrinidae Genus Vitrina
VitrinapellucidaalaskanaW. H.Dall,1905.Landand Fresh Water Mollusca, Harriman Alaska Expedition, 13:37. T.L.: Carson Valley, Churchill Co., Nevada.
(western glass-snail)
General Distribution--This species generally has been reported in the American literature as Vitrina alaskana. Bequaert and Miller (1973:147) ascertained that "V. alaskana agreesinshellandgenitaliawithOldWorld V.pellucida(O.F. Müller,1774),ofwhichitistheAmericansubspecies." Thus construed, V. pellucida is of Holarctic distribution. The subspeciesalaskanaoccursinthewesternNearcticregionfrom Alaska south to California, Arizona, and N e w Mexico.
New Mexico Distribution and Habitat--Vitrinapellucida
alaskanaisfoundinhighermountainsinNew Mexicofromthe
Sacramento-Sierra Blanca complex and the Mogollon
Mountains northward. It is typical of the Canadian and Hudsonian Life Zones in New Mexico mountains. Live
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