Search tool	Example of search string in box	What that means to the database
* = "wildcard". Allows a partial letter string to be entered and implies either no or various extension on this letter string	Hyl*	Will find all uses of "Hyl . . ." anywhere in a record: e.g., Hylarana, Hyla, Hylidae, Hylinae, Hylaedactyla.
* = "wildcard". Allows a partial letter string to be entered and implies either no or various extension on this letter string	*Hyla	Will find all uses of ". . . hyla" anywhere in a record: e.g., Hyla, Hylidae, Plectrohyla, Ptychadena hylaea, Adenomera hylaedactyla
	Hyla	Will find all records that contain stand-alone uses of Hyla: e.g., Hyla, Hyla arenicolor
Strings of words without quotation marks	Lithobates pipiens	Interprets this as "Lithobates OR pipiens" so will find the union of all records that contain either "Lithobates" or "pipiens": e.g., Lithobates omiltemanus, Hylorana pipiens
Strings of word with quotation marks	"Lithobates pipiens"	Interprets this as "Lithobates AND pipiens" so will return all records that have the character string "Lithobates pipiens" anywhere within a record: e.g., all members of the Lithobates pipiens complex.
AND statement. Means that the results of the search must include both words held together by an AND	Lithobates AND pipiens	Same as "Lithobates pipiens"
OR statement. Means that the results of the search will all records that have either of the terms held together by an OR	Lithobates OR "Costa Rica"	Recovers all records that contain the word "Lithobates" or "Costa Rica": 402 records inasmuch as this will include all records for the entire amphibian fauna of Costa Rica
Combining Boolean operators within the Basic Search box (AND, OR, NOT, quotation marks)	Lithobates AND "Costa Rica" NOT forreri	Recovers only records that contain the word Lithobates AND "Costa Rica", but excludes any record that contains the word "forreri" in any part of the record: 9 records
Printable HELP file

Search tool	Example of search string in box	What that means to the database
* = "wildcard". Allows a partial letter string to be entered and implies either no or various extension on this letter string	Hyl*	Will find all uses of "Hyl . . ." anywhere in a record: e.g., Hylarana, Hyla, Hylidae, Hylinae, Hylaedactyla.
* = "wildcard". Allows a partial letter string to be entered and implies either no or various extension on this letter string	*Hyla	Will find all uses of ". . . hyla" anywhere in a record: e.g., Hyla, Hylidae, Plectrohyla, Ptychadena hylaea, Adenomera hylaedactyla
Single word	Hyla	Will find all records that contain stand-alone uses of Hyla: e.g., Hyla, Hyla arenicolor
Strings of words without quotation marks	Lithobates pipiens	Interprets this as "Lithobates OR pipiens" so will find the union of all records that contain either "Lithobates" or "pipiens": e.g., Lithobates omiltemanus, Hylorana pipiens
Strings of word with quotation marks	"Lithobates pipiens"	Interprets this as "Lithobates AND pipiens" so will return all records that have the character string "Lithobates pipiens" anywhere within a record: e.g., all members of the Lithobates pipiens complex.
AND statement. Means that the results of the search must include both words held together by an AND	Lithobates AND pipiens	Same as "Lithobates pipiens"
OR statement. Means that the results of the search will all records that have either of the terms held together by an OR	Lithobates OR "Costa Rica"	Recovers all records that contain the word "Lithobates" or "Costa Rica": 402 records inasmuch as this will include all records for the entire amphibian fauna of Costa Rica
Combining Boolean operators within the Basic Search box (AND, OR, NOT, quotation marks)	Lithobates AND "Costa Rica" NOT forreri	Recovers only records that contain the word Lithobates AND "Costa Rica", but excludes any record that contains the word "forreri" in any part of the record: 9 records
Printable HELP file

Anaxyrus nelsoni (Stejneger, 1893)

Class: Amphibia > Order: Anura > Family: Bufonidae > Genus: Anaxyrus > Species: Anaxyrus nelsoni

Bufo boreas nelsoni Stejneger, 1893, N. Am. Fauna, 7: 220. Holotype: USNM 18742, by original designation. Type locality: "Oasis Valley, [Nye County,] Nevada", USA.

Bufo nelsoni — Savage, 1959, Am. Philos. Soc. Yr. Bk., 1959: 252; Blair, 1972, Evol. Genus Bufo: 350; Stebbins, 1985, Field Guide W. Rept. Amph., Ed. 2: 70; Altig, McDiarmid, Nichols, and Ustach, 1998, Contemp. Herpetol. Inform. Serv., 1998: 7.

Bufo halophilus nelsoni — Frank and Ramus, 1995, Compl. Guide Scient. Common Names Amph. Rept. World: 40. Unsubstantiated arrangement.

Anaxyrus nelsoni — Frost, Grant, Faivovich, Bain, Haas, Haddad, de Sá, Channing, Wilkinson, Donnellan, Raxworthy, Campbell, Blotto, Moler, Drewes, Nussbaum, Lynch, Green, and Wheeler, 2006, Bull. Am. Mus. Nat. Hist., 297: 363.

Bufo (Anaxyrus) nelsoni — Fouquette and Dubois, 2014, Checklist N.A. Amph. Rept.: 306. See comment under Bufonidae regarding how this arrangement is part of a a system that requires widespread paraphyly.

English Names

Amargosa Toad (Schmidt, 1953, Check List N. Am. Amph. Rept., Ed. 6: 62; Conant, Cagle, Goin, Lowe, Neill, Netting, Schmidt, Shaw, Stebbins, and Bogert, 1956, Copeia, 1956: 176; Stebbins, 1966, Field Guide W. North Am. Rept. Amph.: 60; Collins, Huheey, Knight, and Smith, 1978, Herpetol. Circ., 7: 10; Frank and Ramus, 1995, Compl. Guide Scient. Common Names Amph. Rept. World: 40; Collins, 1997, Herpetol. Circ., 25: 11; Crother, Boundy, Campbell, de Queiroz, Frost, Highton, Iverson, Meylan, Reeder, Seidel, Sites, Taggart, Tilley, and Wake, 2001 "2000", Herpetol. Circ., 29: 7; Stebbins, 2003, Field Guide W. Rept. Amph., Ed. 3: 209; Frost, McDiarmid, and Mendelson, 2008, in Crother (ed.), Herpetol. Circ., 37: 4; Collins and Taggart, 2009, Standard Common Curr. Sci. Names N. Am. Amph. Turtles Rept. Crocodil., ed. 6: 6; Frost, McDiarmid, Mendelson, and Green, 2012, in Crother (ed.), Herpetol. Circ., 39: 13; Frost, Lemmon, McDiarmid, and Mendelson, 2017, in Crother (ed.), Herpetol. Circ., 43: 8).

Distribution

Amargosa River Valley, Nye County, Nevada, USA.

Geographic Occurrence

Natural Resident: United States of America, United States of America - Nevada

Endemic: United States of America, United States of America - Nevada

Comment

In the Bufo boreas group of Blair, 1972, Evol. Genus Bufo: 350. Considered by some to be an allopatric subspecies of Anaxyrus boreas. Stebbins, 1985, Field Guide W. Rept. Amph., Ed. 2: 70, recognized this allopatric and morphologically distinct population as a distinct species without discussion. Subsequently Altig, McDiarmid, Nichols, and Ustach, 1998, Contemp. Herpetol. Inform. Serv., 1998: 7, also considered it a distinct species, and although no formal discussion of this change was provided, they did note its allopatry as well as fixed differences between larvae and larval habitats. Morphological distinctiveness of the two forms is not controversial. Stebbins, 2003, Field Guide W. Rept. Amph., Ed. 3: 209–210, provided a brief account, figure, and map. Goebel, 2005, in Lannoo (ed.), Amph. Declines: 210–211, discussed the geographic variation, recognized nelsoni as a species and noted other populations of nominal boreas that might be distinct species. Goebel, Smith, Murphy, and Morafka, 2005, in Lannoo (ed.), Amph. Declines: 427–430, provided a detailed account, map, and conservation status. See photograph, map, description of geographic range and habitat, and conservation status (as Bufo nelsoni) in Stuart, Hoffmann, Chanson, Cox, Berridge, Ramani, and Young, 2008, Threatened Amph. World: 188. Goebel, Ranker, Corn, and Olmstead, 2009, Mol. Phylogenet. Evol., 50: 209–225, suggested on the basis of a discussion of mtDNA phylogeography of the Anaxyrus boreas group that Anaxyrus canorus is in a group composed southern California Anaxyrus boreas halophilus. Dodd, 2013, Frogs U.S. and Canada, 1: 132–136, provided an account that summarized relevant literature. Elliot, Gerhardt, and Davidson, 2009, Frogs and Toads of N. Am.: 176–177, provided an account, photos, and advertisement call. Altig and McDiarmid, 2015, Handb. Larval Amph. US and Canada: 175–177, provided an account of larval morphology and biology.

External links:

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For access to general information see Wikipedia
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For access to relevant technical literature search Google Scholar
For images search CalPhoto Images and Google Images
To search the NIH genetic sequence database, see GenBank
For additional information see AmphibiaWeb report
For information on conservation status and distribution see the IUCN Redlist
For information on distribution, habitat, and conservation see the Map of Life
For related information on conservation and images as well as observations see iNaturalist
For access to available specimen data for this species, from over 350 scientific collections, go to Vertnet.