Crayfishes (Decapoda: Cambaridae) of Oklahoma: identification, distributions, and natural history Author Morehouse, Reid L. Author Tobler, Michael text Zootaxa 2013 3717 2 101 157 journal article 10.11646/zootaxa.3717.2.1 fad4163f-156b-4f1a-a5e9-c9f48df52e0a 1175-5326 248539 C8CDC011-974C-48B4-9E03-88F570EEDE13 Procambarus clarkii (Girard, 1852) : Red Swamp Crawfish General charateristics. Adults rarely exceed 160 mm in total length. The carapace is laterally compressed with small tubercles running along its sides and the areola is closed. The rostrum has a trough-like depression with thick lateral margins and spines extending from the acumen. Chelae are slender and are covered in tubercles, with the largest occurring along the inside margins of the palms. In form I males, gonopods have four short, bladelike terminal processes that strongly curve laterally to the midline. Gonopods also have a shoulder on the cephalic surface. In females, the annulus ventralis lacks a definite fossa, but has two anterior tubercles (Taylor & Schuster, 2004). Life coloration. This species is variable in color (Walls, 2009; personal observation), but in Oklahoma, the background color usually is deep red to burgundy. The abdomen exhibits a broad, black, wedge shaped stripe running longitudinally ( Figure 75 ). Tubercles on the chelae are light tan to cream. The ventral side ranges from dark cream to light cream depending on habitat. Similar species. In Oklahoma, P . clarkii closely resembles P . acutus (see P . acutus for species differences). Distribution and habitat. Procambarus clarkii is widely distributed and naturally occurs along the Gulf Coastal Plain from northeastern Mexico east to the Florida panhandle, and northward along the Mississippi River to southeastern Missouri and southwestern Illinois (Page, 1985; Pflieger, 1996; Taylor & Schuster, 2004; Walls, 2009). Procambarus clarkii is an important aquaculture species (Walls, 2009) and has been introduced and has established populations throughout much of the United States due to the aquarium trade, fishermen, and human food consumption (Taylor et al. , 2007). In Oklahoma, P . clarkii occurs naturally in the extreme southeastern corner where the Gulf Coastal Plain reaches into the state. Procambarus clarkii inhabits a wide variety of habitats, including swamps, flooded ditches, creeks, and will burrow to follow receding water tables as it is a secondary burrower. Substrate in creeks included sandy silt with woody debris and rooted vegetation. Our ecological niche model suggests that the southern half of Oklahoma (along the Red River) provides suitable environmental conditions for P . clarkii ( Figure 76 ). Life history. Reproduction occurs from July to October throughout most of its range (Pflieger, 1996). Form I males have been collected from May through January, while females with eggs or young have been collected in September (Penn, 1943; Pflieger, 1996). Procambarus clarkii is able to reproduce two times a year (Huner, 2002). In Oklahoma, form I males were found in June and October, while form II males and females are found year round. No ovigerous females or females with young were found during our collecting efforts. Syntopic species. Cambarellus puer , Faxonella blairi , and Procambarus acutus . Conservation status. AFS: Currently Stable; Heritage Rank: Widespread (G5); IUCN: Least Concern; ODWC: Not Listed. Additional resources. Barbaresi et al. (2004); Chucholl (2011, 2013); Deng et al. (1993); Pearl et al. (2013); Simon et al. (2005).