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.[4][6] The species name, Faxonius neglectus, was previously Orconectes neglectus (before this, Faxonius was a subgenus of Orconectes[5]). Faxonius was declared its own genus in 2017 by Crandall & De Grave,[3] as many previously thought Orconectes species were found to not reside in caves (a quality of Orconectes).[3]
| Faxonius neglectus | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Malacostraca |
| Order: | Decapoda |
| Suborder: | Pleocyemata |
| Family: | Cambaridae |
| Genus: | Faxonius |
| Species: | F. neglectus
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| Binomial name | |
| Faxonius neglectus | |
| Subspecies[4] | |
| Synonyms[1] | |
Description and ecology edit
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.[4][6][7] 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.[8]
Evidence of sexual dimorphism has not been observed to be present for this species. Adult carapace length is an average of 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.[9] Mating is polygonous, resulting in size based dominance.[10]
Like many other decapods, F. neglectus consumes algae and detritus within the environments that they occupy.[11]
Males edit
In F. neglectus males, there is the presence of the pleopods (swimmerets) being curved towards the tail.[8] 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.[9] The average maximum age for F. n. chaenodactylus males is 5 years, with the average age being 3 years.[10]
Females edit
The average maximum age for F. n. chaenodactylus females is 4 years, with the average age being 3 years.[10]
Habitat edit
Native range edit
Faxonius neglectus has two allopatric populations:
Faxonius neglectus neglectus edit
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.[4][6] 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).[6] 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.[6]
Faxonius neglectus chaenodactylus edit
Restricted to drainages of the White River in both Arkansas and Missouri.[7][12]
Invasive range edit
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.[8] F. neglectus is an invasive species in the Spring River (Arkansas) drainage of the Ozarks. Where F. neglectus colonizes, the native species, Orconectes eupunctus and Cambarus hubbsi, are no longer present, despite having been previously observed in those areas.[13]
References edit
- ^ a b Adams, S., Schuster, G.A. & Taylor, C.A. 2010. Orconectes neglectus. The IUCN Red List of Threatened Species 2010: e.T153807A4547575. https://dx.doi.org/10.2305/IUCN.UK.2010-3.RLTS.T153807A4547575.en. Accessed on 06 February 2024.
- ^ Faxonius neglectus | NatureServe Explorer. (n.d.). Retrieved February 7, 2024, from https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.119078/Faxonius_neglectus
- ^ a b c d e Crandall, K. A., & De Grave, S. (2017). An updated classification of the freshwater crayfishes (Decapoda: Astacidea) of the world, with a complete species list. Journal of Crustacean Biology, 37(5), 615–653. https://doi.org/10.1093/jcbiol/rux070
- ^ a b c d Magoulick, D. D., Wynne, K. C., & Clark, J. (2022). Morphological traits related to potential invasiveness of two subspecies of the crayfish Faxonius neglectus. River Research and Applications, 38(8), 1510–1518. https://doi.org/10.1002/rra.4024
- ^ a b Faxon, W . 1885. Preliminary catalogue of the crayfishes of Kansas. Bulletin of the Washburn College Laboratory of Natural History, 1: 140–142..
- ^ a b c d e Schainost, Steven C. (2011). "The ringed crayfish, Orconectes neglectus neglectus, in Nebraska with a revision of its distributional range". Transactions of the Nebraska Academy of Sciences and Affiliated Societies. 32: 59–68.
- ^ a b Wagner, Brian K.; Taylor, C. A.; Kottmyer, Mark D. (2010). "Status and distribution of the gapped ringed crayfish, Orconectes neglectus chaenogactylus, in Arkansas". Journal of the Arkansas Academy of Science. 64: 115–122.
- ^ a b c Daniels, R. A., Murphy, D. C., & Klemens, M. W. (2001). Orconectes neglectus Is Established in the Northeast. Northeastern Naturalist, 8(1), 93–100. https://doi.org/10.2307/3858265
- ^ a b Price, J. O., & Payce, J. F. (1984). Postembryonic to Adult Growth and Development in the Crayfish Orconectes neglectus chaenodactylus Williams, 1952 (Decapoda, Astacidea). Crustaceana, 46(2), 176–194.
- ^ a b c Price, J. O., & Payne, J. F. (1984). Size, Age, and Population Dynamics in an R-Selected Population of Orconectes neglectus chaenodactylus Williams (Decapoda, Cambaridae). Crustaceana, 46(1), 29–38.
- ^ Evans-white, M., Dodds, W. K., Gray, L. J., & Fritz, K. M. (2001). 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. Hydrobiologia, 462(1–3), 131–144. https://doi.org/10.1023/A:1013182100150
- ^ United States Geological Survey. "gap ringed crayfish (Faxonius neglectus chaenodactylus) - Species Profile". USGS Nonindigenous Aquatic Species Database. Retrieved 3 April 2024.
- ^ Magoulick, D. D., & DiStefano, R. J. (2007). Invasive Crayfish Orconectes neglectus Threatens Native Crayfishes in the Spring River Drainage of Arkansas and Missouri. Southeastern Naturalist, 6(1), 141–150.
External links edit
- "USGS Nonindigenous Aquatic Species – Ringed Crayfish". US Geological Survey.
