Faxonius maletae

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]

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]

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]

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]

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]

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]

• Hathawayi group
  • F. perfectus
  • F. hathawayi
  • F. h. blacki
• Difficilis group
  • F. maletae
  • F. difficilis

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

• Data related to Orconectes maletae at Wikispecies