Page 54 - Land Snails of New Mexico

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described in the 1800s or early 1900s, this poses a serious
taxonomicproblem,sometimesexacerbatedbylackofprecise
data as to where type material actually was collected; for
example, as in S. avara and S. grosvenori, discussed below. There are numerous older records of succineids from N e w
Mexicointheliterature.Unfortunately,theproblemsnoted aboverendertheserecordstaxonomicallyunreliableforthemost part. However, studies by Franzen (1971, 1982) and, most recently,anannotatedlistingofsuccineidsfromNewMexicoby Wu (1993),havecontributedtowardsabetterunderstandingof succineids in the state.
Genus Oxyloma
Oxyloma retusum (I. Lea, 1834, as Succinea). Transactions of the American Philosophical Society, 5:117, Pl. 19, Fig. 86. T.L. Ohio near Cincinnati, (blunt ambersnail)
Wu (1993:93)assignedlivingspecimensofanOxyloma
foundintheareaofMescalero,OteroCo.,toO.retusum.The
species occurs along the banks of the Tularosa River. N u m e r o u s
specimens have been observed in a park along the river in the
town ofMescalero.Italsooccursnearthefishhatcheryatthe
west side of Mescalero and up Tularosa Canyon, probably to
near the headsprings of the Tularosa River. The floodplain and
stream in this section support a lush growth of moisture-loving
and aquatic plants, such as cattails, sedges, rushes, and
watercress. Especially important to O. retusa seem to be the
emergent leaves and stems of watercress (Nasturtium
officinale), which flourishes in the stream. These snails are
found commonly on watercress and other plants overhanging the
water, or not far away. T h e floodplain is m a r s h y in s o m e places.
Judging by the nature of exposed Holocene sediments, this
marshy habitat must have continued downstream from Mescaleroforsome 15milestotheleveloftheTularosaBasin
before stream entrenchment took place in the last century. Fossil Oxyloma shells are common in such sediments. Oxyloma retusum is not found upstream from the Tularosa River headsprings, where marshes and lush, riparian, vegetation abruptly terminate at present.
In N e w Mexico, w e have seen living O x y l o m a only from this short segment of the Tularosa River Valley; however, Dr. RaymondW.NeckrecentlyinformedusoffindingOxylomas along Fresnal Canyon, above High Rolls, Otero Co. Oxyloma retusum may occur in other marshy, riparian habitats in the Sacramento Mountains. Remaining marshy or wetland habitats inNew Mexico,whereotherrarespeciesalsomaypersevere, shouldbesoughtoutandgivenfurtherattention.Oxyloma fossil specimens found in various parts of N e w Mexico indicate that the genus w a s m o r e c o m m o n in previous times than at present.
Genus Succinea
Succinea luteola A. A. Gould, 1848. Proceedings of the Boston Society of Natural History, 3:37. T. L.; Bequaert and Miller discuss the T.L. (1973:155): "Texas, without morepreciselocality,W.G.Binney's(1885:497)listingof 10 shells (at U.S. Nat Mus. No. 39757) from Corpus Christi as 'type original lot, seems to preempt Pilsbry and
Ferriss' (1906:158) selection of Galveston as T.L.; R. I. Johnson (1961:106) mentions syntypes atMus. Comp. Zool, but does not select a holotype or a T.L." (Mexico ambersnail)
General and New Mexico Distribution--Hubricht
(1985:Map 123)mappedthisspeciesasoccurringintheGulf Coastal states from the Florida Panhandle to Texas. However, mostrecordsarefromTexas,whereitiscommon inthesouthern two-thirdsofthestate.ThisspeciesextendsuptheRioGrande and Pecos River Valleys into West Texas and, in the case of the RioGrandeValley,intosouthernNew Mexico (probablyalsoin the Pecos River Valley, but this has not been confirmed).
Habitat--In the Mesilla Valley, Doña Ana Co., we have found S. luteola living along irrigation ditches, where the snails were located on the wet banks of canals only a few inches above the water line, a habitat they often share with the basommatophoran snail Fossaria bulimoides.
Succinea vaginacontorta C. B. Lee, 1951. University of Michigan M u s e u m of Zoology, Occasional Papers, 5 3 3 : 1 7, Pl. 2, Fig. 1. T.L.: M e a d e Co., Kansas.
Dr. Dorothea Franzen dissected specimens of a succineid, which Metcalfhad collectedfrom near Romeroville, San Miguel Co., New Mexico, and assigned them to S. vaginacontorta (1971:137).Wu (1993:94)assignedspecimensfromColfaxCo. (1 locality) and Union Co. (2 localities) to this species. These
determinations suggest that S. vaginacontorta is a species of northeastern New Mexico. As understood by Franzen (1971:141), S. vaginacontorta is a "xerophilous" species, rangingfromSouthDakotatoTexasandNewMexicointhe High Plains and Rocky Mountain foothills.
Hubricht(1985:15,Map 117)placedS.vaginacontortain t h e s y n o n y m y o f S. i n d i a n a P i l s b r y , 1 9 0 5 , a n d m a p p e d t h e H i g h Plains records noted by Franzen, apparently including the record from Romeroville, as pertaining to S. indiana. Neck also r e c o r d e d ( 1 9 9 0 ) .S. i n d i a n a f r o m t h e T e x a s P a n h a n d l e . S o m e problems with this employment of S. indiana are suggested by Hubricht's map, because itstype locality is in Posey Co., Indiana, whereas nearest records to the type locality are in Central Alabama, south-central Arkansas, and southwestern Missouri. It seems more conservative, at this time, to use the name v a g i n a c o n t o r t a , a s p e c i e s w i t h its T . L . i n t h e H i g h P l a i n s , f o r t h e western populations considered here.
Succinea grosvenori I. Lea, 1864. Proceedings of the Academy ofNaturalSciencesofPhiladelphia, 16:109. T.L. As summarized by Bequaert and Miller (1973:156). "described from Santa Rita Valley, Kansas, and Alexandria, Louisiana, no precise T.L. selected so far." (Santa Rita ambersnail)
The epithetgrosvenori often has been applied to relatively small succineids from the Great Plains and southern Rocky Mountainsstates.Pilsbry(1948:821)listeditinNew Mexico from near Las Vegas, the San Andres Mountains, Tularosa (Otero Co.), and "Grant" (presumably Grants in Cibola Co.).