Hershler r (47 risultati)

Pamphlet. Condizione: Very Good. No Jacket (As Issued). General yellowing.

Paper Back. Condizione: Good.

Paper Back. Condizione: Good. General yellowing.

19pp, 5 figs, Printed Card Cover, VGC.

Trade Paperback. Condizione: Near Fine. First Edition. 4to. - over 9¾ in. - 12 in. Paperback edition. Slight cover wear yet wraps clean, two small creases to wrap spine, tight binding, interior text clean. Near Fine copy.

Condizione: Very Good. iii, 41, 18 b/w text figs. . PB. Vg. Smithsonian Contributions to Zoology 583.

Soft cover. 547) 0.0.

Morphological variation among members of the genus Tryonia (and its subgenus Paupertryonia) is congruent with a recently published phylogenetic analysis based on mtDNA sequences that showed that these taxa are polyphyletic assemblages of ecologically similar snails. Tryonia is reconstituted as a North and Central American monophyletic subunit of the subfamily Cochliopinae based on a synapomorphy of posterodorsal insertion of the vas deferens into the prostate gland. Presumably derived modifications of the shell, radular teeth, and genitalia unite groups of species within this genus. Tryonia is redefined and 18 species are recognized in the genus. Congeners are T. aequicostata (Pilsbry, 1890a), distributed in the Florida peninsula; T. cheatumi (Pilsbry, 1935) and T. circumstriata (Leonard and Ho, 1960), Rio Grande basin; T. hertleini (Drake, 1956), interior drainage of northeast Mexico; T. clathrata Stimpson, 1865, and T. gilae Taylor, 1987, lower Colorado River basin; T. angulata Hershler and Sada, 1987, T. elata Hershler and Sada, 1987, T. ericae Hershler and Sada, 1987, T. margae Hershler, 1989, T. monitorae Hershler, 1999, T. rowlandsi Hershler, 1989, T. salina Hershler, 1989, and T. variegata Hershler and Sada, 1987, southern Great Basin; T. porrecta (Mighels, 1845), lower Colorado River basin, Great Basin, Hawaii; T. quitobaquitae Hershler in Hershler and Landye, 1988, Rio Sonoyta basin ; T. imitator (Pilsbry, 1899), southern California coast; and T. exigua (Morelet, 1851), Lake Peten Itza, Guatemala. Tryonia protea (Gould, 1855 ) is found to be a junior synonym of Paludina porrecta Mighels, 1845. Tryonia kosteri Taylor, 1987, from the Pecos River basin, is found to be a member of the genus Durangonella Morrison, 1945, which was previously known only from the Mexican Plateau. A new North American genus, Pseudotryonia Hershler, is erected for three species previously placed in Tryonia. Pseudotryonia is diagnosed by a combination of genitalic characters. Its congeners are P. brevissima (Pilsbry, 1890b), Florida panhandle; P. adamantina Taylor, 1987, and P. alamosae Taylor, 1987, Rio Grande basin; and an undescribed species from the Tombigbee River basin. A ne w monotypic genus, Ipnobius Hershler, is erected for Tryonia robusta Hershler, 1989, from Death Valley, California. Ipnobius is diagnosed by genitalic autapomorphies. Lectotypes are designated for Melania exigua Morelet, and Amnicola protea Gould. 53 pp., 29 figs, br. 4.…

Condizione: Very Good. iv, 115, 53 text figs. . PB. Vg. Smithsonian Contributions to Zoology 554.

3 pp., 4.

18 pp., 8 figs, 6 tabs, gr. 8.

11 pp., 8 figs, gr. 8.

16 pp., 7 figs, 9 tabs, 4.

Newly obtained and previously published sequences of the cytochrome c oxidase subunit I (COI) gene were analyzed to examine the biogeographic assembly of the caenogastropod fauna (belonging to the families Assimineidae, Cochliopidae, and Hydrobiidae) of an isolated spring along the lower Colorado River in southern Nevada (Blue Point Spring). Based on available COI clock calibrations, the three lineages that comprise this fauna are 2.78?1.42 million years old, which is roughly coeval or slightly younger than the age of Blue Point Spring (inferred from local fossil spring deposits). Two of the lineages?endemic Pyrgulopsis coloradensis and Assiminea aff. infima?are most closely related to snails in the Death Valley area (well to the west) and likely colonized Blue Point Spring by transport on birds. A single haplotype was detected in both of these snails, suggesting that they may have only recently colonized Blue Point Spring. The third lineage?endemic Tryonia infernalis, newly described herein based on morphological and molecular evidence?is most closely related to a geographically proximal species in a lower Colorado River tributary (T. clathrata); the split between these taxa may be the product of vicariance (severance of a prior drainage connection) or a separate jump dispersal event. The considerable genetic diversity in T. infernalis (three haplotypes differing by 0.6% mean sequence divergence) suggests a possibly lengthy history of local differentiation. Our findings also identify Blue Point Spring as a new micro-hotspot of groundwater-dependent biodiversity in Nevada and will assist ongoing efforts to protect and conserve these imperiled ecosystems. 16 pp., 6 figs, 2 tabs, gr. 8.…

Undescribed freshwater snails (Amnicolidae: Colligyrus) from the Mount Hood region (northwestern United States) identified as a new species (commonly known as the Columbia duskysnail) in grey literature have been provided federal protection under the ?survey and manage? provisions of the Northwest Forest Plan and have been placed on conservation watch lists. However, there are no published studies of the identity of these snails aside from a molecular phylogenetic analysis which delineated a close relationship between the single sampled population and C. greggi, which is distributed more than 750 km to the east of the Mount Hood area. Here we examine the taxonomic status of the Columbia duskysnail based on additional molecular sampling of mitochondrial DNA sequences (COI) and morphological evidence. We found that the Columbia duskysnail is not a monophyletic group and forms a strongly supported clade with C. greggi. The COI divergence between these broadly disjunct groups (2.1%) was somewhat larger than that within C. greggi (1.0%) but considerably less than that among the three currently recognized species of Colligyrus (8.7?12.1%). Additionally we found that the Columbia duskysnail and C. greggi cannot be consistently differentiated by previously reported diagnostic characters (size and shape of shell spire, pigmentation of body and penis) and are closely similar in other aspects of morphology. Based on these results we conclude that the Columbia duskysnail is conspecific with C. greggi. 13 pp., 6 figs, 4 tabs, gr. 8.…

12 pp., 8 figs, gr. 8.

7 pp., 21 figs, 4.

583) 0.0.

, 37 figs, wrps 0.0.

, 49 figs/pls, 4to, wrps 0.0.

We describe two new species of pebblesnails (Lithoglyphidae: Fluminicola) from southwest Oregon based on morphologic and mitochondrial DNA (COI, cytB) evidence. Fluminicola umpquaensis sp. n., which had been traditionally identified as F. virens prior to the recent restriction of the latter to the lower Columbia River drainage, lives in lotic habitats in the Umpqua River basin. This species is readily distinguished from closely related F. gustafsoni and F. virens by shell and anatomical characters, and by its mtDNA sequences (divergence >3.6% for both genes). Fluminicola fresti sp. n. ranges among lotic habitats in the North Umpqua River basin, and in the upper Rogue River drainage north of Little Butte Creek. This species differs from other congeners by >9.1% for both genes and is distinguished from closely similar and geographically proximal F. multifarius by several anatomical characters. Additionally, new records are provided for F. multifarius from the upper Rogue River basin south of Little Butte Creek, which extend the geographic range of this species about 80 km northward from the Sacramento River headwater region. This continues a recent series of taxonomic papers on the poorly known and little studied pebblesnail fauna of the vast Pacific watershed from northern California to southern British Columbia. New taxa: Fluminicola umpquaensis n. sp., Fluminicola fresti n. sp. 20 pp., 6 figs, gr. 8.…

1. Detailed morphological data for H. truncata are given as a standard for comparing species of Hydrobia,worldwide stressing the importance of quantitative data, scaling and allometry. The need for careful examination of all organ systems is stressed. Useful data for comparing species have been derived, in order of importance, from the female reproductive system, male reproductive system including details of penial filament, appendages, glands; radula, mantle-pallial structures, head pigment patterns, shell allometry. 2. Three populations of Hydrobia truncata from Maryland, New Jersey, and Massachusetts respectively were compared morphologically and ecologically with H. totteni and H. salsa of Massachusetts and Hydrobia from northern Europe. Three species of Hydrobia inhabit the same geographic region in Massachusetts. 3. H. truncata differs from H. totteni morphologically and ecologically. Shell size and allometry separate the species, as well as differences in eight anatomical character states. However, the complete anatomy of H. totteni has yet to be done. 4. H. truncata apparently increases in size and increases the length of body whorl relative to overall length from south to north. Allometry of Massachusetts H. truncata equals that of H. totteni when H. truncata exceeds H. totteni in size. 25 pp., 10 figs, gr. 8.…

23 pp. 12 figs, geh. 4.

46 pp., ill., gr. 8.

32 pp., 15 figs, 4.

41 pp., 18 figs on pls, stapled gr. 8.

New taxon: Fontigens morrisoni n. sp. 49 pp., 37 figs, broch. 4.