Faxonius neglectus

{{Short description|Species of freshwater crayfish}} {{Speciesbox | image = Ringed crayfish - MDC gov.jpg | image_caption = | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn">{{cite iucn |author=Adams, S. |author2=Schuster, G.A. |author3=Taylor, C.A. |year=2010 |title=''Orconectes neglectus'' |volume=2010 |article-number=e.T153807A4547575 |doi=10.2305/IUCN.UK.2010-3.RLTS.T153807A4547575.en |access-date=6 February 2024}}</ref> | status2 = G5 | status2_system = TNC | status2_ref = <ref name="NatureServe">{{cite web|title=''Faxonius neglectus'' |website= NatureServe Explorer |access-date= February 7, 2024 |url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.119078/Faxonius_neglectus}}</ref> | genus = Faxonius | species = neglectus | authority = (Faxon, 1885)<ref name="taxa"/> | subdivision_ranks = Subspecies | subdivision_ref = <ref name="morph"/> | subdivision = *''F. n. neglectus'' (Faxon, 1885)<ref name="taxa"/> *''F. n. chaenodactylus'' (Williams, 1952)<ref name="taxa"/> | synonyms = ''Orconectes neglectus'' Faxon, 1885<ref name="ogtaxa">{{cite journal|author=Faxon, W. |year=1885|title= Preliminary catalogue of the crayfishes of Kansas|journal= Bulletin of the Washburn College Laboratory of Natural History|volume= 1|pages= 140–142}}</ref> | synonyms_ref = <ref name="iucn"/> }} '''''Faxonius neglectus''''', a species of freshwater crayfish also known as the '''ringed crayfish''', is native to Central North America, with two major disjunct areas of distribution in the Ozarks and around Nebraska.<ref name="morph"/><ref name="nebraska_range">{{cite journal |last1=Schainost |first1=Steven C. |title=The ringed crayfish, ''Orconectes neglectus neglectus'', in Nebraska with a revision of its distributional range |journal=Transactions of the Nebraska Academy of Sciences and Affiliated Societies |date=2011 |volume=32 |pages=59–68}}</ref> The species name, ''Faxonius neglectus'', was previously '''''Orconectes neglectus''''' (before this, ''Faxonius'' was a subgenus of ''Orconectes'').<ref name="ogtaxa"/> ''Faxonius'' was declared its own genus in 2017 by Crandall & De Grave,<ref name="taxa"/> as many previously thought ''Orconectes'' species were found to not reside in caves (a quality of ''Orconectes'').<ref name="taxa">{{cite journal|author=Crandall, K. A.|author-link=Keith A. Crandall |author2=De Grave, S. |year=2017|title= An updated classification of the freshwater crayfishes (Decapoda: Astacidea) of the world, with a complete species list|journal= Journal of Crustacean Biology|volume= 37 |issue=5|pages= 615–653 |doi=10.1093/jcbiol/rux070}}</ref>

== Description and ecology == There are two subspecies of ''F. neglectus'': '''''F. neglectus chaenodactylus''''' (also known as the '''gapped ringed crayfish''' or the '''gap-ringed crayfish''') and '''''F. neglectus neglectus'''''.<ref name="morph"/><ref name="nebraska_range"/><ref name="arkansas_gapped_ringed">{{cite journal |last1=Wagner |first1=Brian K. |last2=Taylor |first2=C. A. |last3=Kottmyer |first3=Mark D. |title=Status and distribution of the gapped ringed crayfish, ''Orconectes neglectus chaenogactylus'', in Arkansas |journal=Journal of the Arkansas Academy of Science |date=2010 |volume=64 |pages=115–122}}</ref> ''F. neglectus'' has a uniquely marked decapod anatomy, which includes a wide ring on the rostrum in combination with a dark brown wide ring on the dactyl and propodus of the crayfish's chelipeds, ending in bright red/orange. The third maxilliped ends in a scalloped appearance. The color of the carapace can range from a light brown or yellow color, just rear of the cephalic groove, being banded by a dark brown ring.<ref name="northeast"/>

thumb|''Faxonius neglectus neglectus'', showcasing distinctive banded claws that are unique to this species.

Evidence of sexual dimorphism has not been observed to be present for this species. Adult carapace length is an average of {{cvt|32|mm}} for males and females. During ''F. n. chaenodactylus'''s initial year of life, the average number of molts performed is 8, followed by 4, 3, 4, 4, and 4 molts for each year after.<ref name="growth">{{cite journal|author=Price, J. O.|author2= Payce, J. F. |year=1984 |title=Postembryonic to Adult Growth and Development in the Crayfish ''Orconectes neglectus chaenodactylus'' Williams, 1952 (Decapoda, Astacidea)|journal= Crustaceana|volume= 46|issue=2|pages= 176–194|doi= 10.1163/156854084X00685 |bibcode= 1984Crust..46..176P }}</ref> Mating is polygonous, resulting in size based dominance.<ref name="size">{{cite journal |author=Price, J. O.|author2= Payne, J. F. |year=1984|title= Size, Age, and Population Dynamics in an R-Selected Population of ''Orconectes neglectus chaenodactylus'' Williams (Decapoda, Cambaridae)|journal= Crustaceana|volume= 46|issue=1|pages= 29–38|doi= 10.1163/156854084X00036 |bibcode= 1984Crust..46...29P }}</ref>

Like many other decapods, ''F. neglectus'' consumes algae and detritus within the environments that they occupy.<ref name="diet">{{cite journal|author=Evans-white, M.|author2= Dodds, W. K.|author3= Gray, L. J. |author4= Fritz, K. M. |year=2001|title= A comparison of the trophic ecology of the crayfishes (''Orconectes nais'' (Faxon) and ''Orconectes neglectus'' (Faxon)) and the central stoneroller minnow (''Campostoma anomalum'' (Rafinesque)): Omnivory in a tallgrass prairie stream|journal= Hydrobiologia|volume= 462|issue=1–3 |pages=131–144|doi=10.1023/A:1013182100150|bibcode= 2001HyBio.462..131E}}</ref>

=== Males === In ''F. neglectus'' males, there is the presence of the pleopods (swimmerets) being curved towards the tail.<ref name="northeast"/> Males have been documented to reach maturity within 8 months, but the growth of immature ''F. n. chaenodactylus'' is dependent upon temperature fluctuations during this time.<ref name="growth"/> The average maximum age for ''F. n. chaenodactylus'' males is 5 years, with the average age being 3 years.<ref name="size"/>

=== Females === The average maximum age for ''F. n. chaenodactylus'' females is 4 years, with the average age being 3 years.<ref name="size"/>

== Habitat ==

=== Native range === ''Faxonius neglectus'' has two allopatric populations:

====''Faxonius neglectus neglectus''====

The native range for ''F. n. neglectus'' is disjunct between a population in the Boston Mountains and Ozark Highlands of Arkansas, Kansas, Missouri, and Oklahoma, and a western and central Nebraska-centered population also occurring in adjacent Colorado, Kansas, and Wyoming.<ref name="morph">{{cite journal|author=Magoulick, D. D.|author2= Wynne, K. C.|author3= Clark, J. |year=2022 |title=Morphological traits related to potential invasiveness of two subspecies of the crayfish ''Faxonius neglectus''|journal= River Research and Applications|volume= 38|issue=8|pages= 1510–1518 |doi=10.1002/rra.4024|bibcode= 2022RivRA..38.1510M}}</ref><ref name="nebraska_range"/> There are also isolated records of this taxon western Colorado west of the continental divide (i.e., in the Pacific drainage and not the Atlantic drainage like other known populations).<ref name="nebraska_range"/> Many of these northern populations were once considered relict populations, but recent work has shown that ''F. n. neglectus'' is widespread within the western two thirds of Nebraska and surrounding adjacent drainages, including the basins of the Kansas (mostly the tributaries of the Republican and Big Blue), the Niobrara, and the Platte (including the Loup) rivers.<ref name="nebraska_range"/>

====''Faxonius neglectus chaenodactylus''====

Restricted to drainages of the White River in both Arkansas and Missouri.<ref name="arkansas_gapped_ringed"/><ref name="usgs_gap_ringed">{{cite web |last1=United States Geological Survey |title=gap ringed crayfish (''Faxonius neglectus chaenodactylus'') - Species Profile |url=https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=2614 |website=USGS Nonindigenous Aquatic Species Database |access-date=3 April 2024 |language=en}}</ref>

=== Invasive range === ''F. neglectus'' has been documented as an invasive species in the Hudson River's Croton River drainage of southeastern New York, and the Housatonic River drainage of Connecticut.<ref name="northeast">{{cite journal|author=Daniels, R. A.|author2= Murphy, D. C.|author3= Klemens, M. W. |year=2001|title= ''Orconectes neglectus'' Is Established in the Northeast|journal= Northeastern Naturalist|volume= 8|issue=1|pages= 93–100 |doi=10.2307/3858265|jstor= 3858265}}</ref> ''F. neglectus'' is an invasive species in the Spring River (Arkansas) drainage of the Ozarks. Where ''F. neglectus'' colonizes, the native species, ''Faxonius eupunctus'' and ''Cambarus hubbsi'', are no longer present, despite having been previously observed in those areas.<ref name="invasive">{{cite journal|author=Magoulick, D. D.|author2= DiStefano, R. J. |year=2007|title= Invasive Crayfish ''Orconectes neglectus'' Threatens Native Crayfishes in the Spring River Drainage of Arkansas and Missouri|journal= Southeastern Naturalist|volume= 6|issue=1|pages= 141–150|doi= 10.1656/1528-7092(2007)6[141:ICONTN]2.0.CO;2 }}</ref>

== References == {{Reflist}}

== External links == *{{cite web|url=https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=2267|title=USGS Nonindigenous Aquatic Species – Ringed Crayfish|publisher=US Geological Survey}} {{Commons}}

Category:Cambaridae Category:Freshwater crustaceans of North America Category:Edible crustaceans Category:Crustaceans described in 1885 Category:Taxa named by Walter Faxon Category:Wikipedia Student Program