Faxonius maletae

Faxonius maletae

Imperiled  (NatureServe)[2]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Family: Cambaridae
Genus: Faxonius
Species:
F. maletae
Binomial name
Faxonius maletae
(Walls, 1972)[3]
Synonyms[3]
  • Orconectes difficilis maletae Walls, 1972
  • Orconectes maletae[1]

Faxonius maletae,[4] sometimes called the Kisatchie painted crayfish or Kisatchie painted crawfish,[5] is a species of crawdad in the Cambaridae family. The specific epithet maletae is in honor of the discoverer's wife, author Maleta M. Walls, who helped collect many of the original specimens.[3] It was originally described as a subspecies of Orconectes difficilis,[3] but later elevated to full species status.[6] The common name refers to the Kisatchie National Forest, near where the original specimens were found in Bayou Santabarb [ceb; wikidata].[3]

Description

Kisatchie painted crawfish are brown or olive with red, blue, and white to yellow markings.[5] The red is mainly on the central joints of the pereiopods, the postorbital ridges, and a little on the posterior margins of the uropods (tail fins) and abdominal segments.[5] The fingers of the long, stout chelae (claws) are in order from tip to base, red, yellow/cream, blue, and greenish brown/brown.[5]

Its cephalothorax is about 40 millimetres (1.6 in) long,[5] to a maximum of 4.4 centimetres (1.7 in).[6] The rostrum (beak) is acuminate and has lateral spines.[5] It has a closed areola (the hourglass shaped lines on the back).[5]

It is very similar to Faxonius difficilis but has a central projection that is longer and more curved, with a more smoothly curved expanded mesial process.[3][6] It can be distinguished from F. palmeri by its shorter gonopods[6] (which may reach the third coxa) and a shorter and stouter central projection.[3] It is fairly indistinguishable from F. hathawayi blacki except that form I (breeding) males have an apex of their first pleopod (swimming leg) that is slender, long, and curved.[5] They only have simple copulatory hooks on their third legs.[6] It is also unique among members of its clade for having a structure like a sulcus caused by a single cephalomedian (anterior) prominence.[7]

Behaviour

Form I males are found in low-water conditions between June and October, peaking in September–October.[6] Males have mating plugs in October.[6] Kisatchie painted crawfish reproduce with the male depositing sperm into an external receptacle under the female's abdomen.[5] She then fertilizes her eggs as she excretes them.[5] Both eggs and hatchlings remain with the mother, held under her body by her pleopods until they are big enough to swim and crawl without assistance.[5] June and July are when juveniles are most commonly found.[6]

Habitat and ecology

F. maletae prefers clear flowing streams with sandy bottoms and plenty of plant litter and rocks.[1] Occasionally it found in reed beds.[1]

It eats carrion and plants.[5]

Distribution

The Kisatchie painted crayfish has a very restricted and fragmented range.[1] It has been found in Rapides,[2] Natchitoches,[8] and Sabine Parishes, Louisiana;[5][6] Upshur,[3] Titus, Franklin, Gregg, Harrison, and Marion Counties, Texas;[8] Pittsburg and Latimer Counties, Oklahoma; and Washington County, Arkansas.[1] By river, it is found in Bayou Teche, Kisatchie Bayou,[5] tributaries of the Red River of the South,[6] and in Cypress Creek.[1] There is also evidence of it interbreeding with F. difficilis in Coal County, Oklahoma.[3] Some consider the observations in Louisiana to be of F. hathawayi[1] or F. h. blacki[2] and not F. maletae.

Phylogenetic study of the Texas populations indicate they are distinct genetically, perhaps even a separate cryptic species.[8] The populations also inhabited separate ecological niches, which may further drive speciation.[8]

Threats

Kisatchie painted crayfish are susceptible to increased sediment in the water, particularly related to agricultural runoff and logging.[1] The loss of shade from their practices also negatively impacts the animal.[5] Habitat destruction is specifically a concern in Louisiana,[9] where local extinction has happened.[1] With this and the disjointed range of the species,[9] the population is in decline.[1][8]

In 1996 the species was listed by the IUCN Red List as being vulnerable, but as of 2010 it is listed as data deficient.[1] NatureServe rated the species as G2 (imperiled) in 2009.[2] The American Fisheries Society rated it "Threatened" in 2007.[9]

Taxonomy

F. maletae was formerly in the Hespericambarus subgenus of Orconectes, originally described by Joseph F. Fitzpatrick Jr.[7] The name derives from the Latin hesperius (literally 'western') and cambarus[7] (lit. 'shrimp'). Members of Hespericambarus included:[7]

However, following the re-classification to Faxonius, no subgenera now exist in the new genus as they were considered not to be monophyletic.[4]

References

  1. ^ a b c d e f g h i j k l Adams, S.; Schuster, G.A. & Taylor, C.A (2010). "Orconectes maletae". IUCN Red List of Threatened Species. 2010: e.T15433A4584468. doi:10.2305/IUCN.UK.2010-3.RLTS.T15433A4584468.en. Retrieved 6 December 2022.
  2. ^ a b c d "Orconectes maletae". NatureServe Explorer An online encyclopedia of life. 7.1. Arlington, Virginia: NatureServe. November 2016. Archived from the original on 17 February 2018. Retrieved 6 December 2017.
  3. ^ a b c d e f g h i Walls, Jerry G. (29 February 1972). "Three New Crawfishes Related to Orconectes difficilis (Faxon) (Decapoda: Astacidae)" (PDF). Proceedings of the Biological Society of Washington. 84 (53): 449–458. ISSN 1943-6327. Retrieved 6 December 2017.
  4. ^ a b Crandall, Keith A; De Grave, Sammy (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. doi:10.1093/jcbiol/rux070.
  5. ^ a b c d e f g h i j k l m n o "Rare Animals of Louisiana Kisatchie painted crawfish" (PDF). Louisiana Department of Wildlife and Fisheries. Baton Rouge, LA. Retrieved 6 December 2017.
  6. ^ a b c d e f g h i j Walls, Jerry G. (April 2009). Crawfishes of Louisiana (PDF). Baton Rouge, LA: LSU Press. pp. 131–132. ISBN 9780807134092. OCLC 255142426. Retrieved 8 December 2017.
  7. ^ a b c d Fitzpatrick, Jr., Joseph F. (25 February 1987). Kensley, Brian (ed.). "The Subgenera of the Crawfish Genus Orconectes (Decapoda: Cambaridae)" (PDF). Proceedings of the Biological Society of Washington. 100 (1): 44–74. ISSN 0006-324X. Retrieved 9 December 2017.
  8. ^ a b c d e Brown, Larrimy Beth (7 April 2017). "Phylogenetic and ecological analysis of two populations of the Kitsatchie Painted Crayfish, Faxonius maletae (Decapoda: Cambaridae)". Biology Theses. Paper 44: 1–63. hdl:10950/576. OCLC 1003859602.
  9. ^ a b c Taylor, Christopher A.; Schuster, Guenter A.; Cooper, John E.; DiStefano, Robert J.; Eversole, Arnold G.; Hamr, Premek; Hobbs III, Horton H.; Robison, Henry W.; Skelton, Christopher E.; Thoma, Roger F. (August 2007). "A Reassessment of the Conservation Status of Crayfishes of the United States and Canada after 10+ Years of Increased Awareness". Fisheries. 32 (8): 372–389. doi:10.1577/1548-8446(2007)32[372:AROTCS]2.0.CO;2. ISSN 1548-8446. OCLC 4902547044.