Page 29 - Land Snails of New Mexico
P. 29
la
1b
la
1b
2a
2b
3a
3b
4a
4b
5a
Sb
6a
6b
7a
7b
8a
8b
9a
Shell3.8-4.8mm inwidth,elevated,withwell-developedribs,brownishperiostracum,LowerandUpper SonoranLifeZones ............................................................ Thysanophorahornii(p.60)
Shell4.5-5.5mm inwidth,notelevated,flatwithalmostnospire,withoutribs,whitishtograyish
periostracum, Transition and higher Life Zones. ................................... Microphysula ingersolli (p.61)
Oreohelicidae
Embryonic shell of about 1.5 whorls with strongly developed, sharply defined radial riblets, species of theBigHatchetMountainsarea ..................................................... Genus Radiocentrum 15
Embryonic shell of 2.0-2.5 whorls, with well-developed growth lines, but not with the crisply defined
radialribletsofRadiocentrum(1a),includesalllivingNew Mexicooreohelicidsexceptthoseofthe BigHatchetMountainsarea .............................................................Genus Oreohelix 2
SpeciesfoundinnorthernNewMexiconorthofU.S.Highway60orofalinefromClovistoQuemado ................3
SpeciesfoundinNewMexicosouthofU.S.Highway60orofalinefromClovistoQuemado .......................5
A speciesoftheZuñiareainLittleColoradoRiverdrainageofextremewesternNew Mexico ... Oreohelixhoughi(p.46)
NotaspeciesoftheZuñiareaofwesternNew Mexico .......................................................4
Shellwidthusually>17mm; shellroundedperipherally,usuallywith2well-defined,dark-brownbands, shellsurfacerelativelysmooth ..............................................Oreohelixstrigosadepressa(p.41)
Shell width usually <17 m m ; shell angular peripherally, variously pigmented from whitish to brown (brown blotches, but seldom with 2 brown bands); growth lines strongly developed, producing rough shell surface (See also 6b below, as thisspecies occurs both north and south ofU.S. Highway 60.)
************************************************************************** Oreohelixneomexicana(p.46) SpecieseastoftheRioGrandeValley ....................................................................6
SpecieswestoftheRioGrandeValley.................................................................... 7
Shell weakly angular, spire dome-shaped, sutures poorly impressed, occurs in the Sierra Blanca Mountains e-------------------------------------------------------------------******** Oreohelixnogalensis(p.42)
Shell sharply angular to carinate, spire comprised of "stair-stepped" whorls with sutures deeply impressed
(also includes characters indicated in 4b, above); living in the Oscura, Gallinas, and M a n z a n o Mountains and fossilelsewhere ............................................................. Oreohelixneomexicana(p.46)
Shellsmall,depressed,<7mm inheight,freshshellswithseveralspiralfringesofcuticularhairs, aspeciesoftheMogollonMountainsinNew Mexico ....................................Oreohelixbarbata(p.47)
Shelldepressedtoelevated,but>7mm inheight,lackingfringesofalianhairs ................................ 8
SpeciesoftheSanMateoandMogollonMountainsandBlackRange ...........................................9
Speciesnotoftheaboveranges(8a) .................................................................... 12
Shellelevated,matureshellover12mm inheight;roundedtoweaklyangularperipherally,usually
well-developed brown bands present, shell relatively smooth. ............................ Oreohelix subrudis (p. 42)
Thysanophoridae
M o s t s h e l l s k e y i n g t o 9 a w i l l b e O . s u b r u d i s , w h i c h o c c u r s i n all t h r e e r a n g e s n o t e d i n 8 a , a b o v e . H o w e v e r , a p o o r l y k n o w n a n d dubious species Oreohelix swopei, with a restricted distribution in the northern Black Range, will key out here, also.
23
