Taxonomy

Worldwide, freshwater crayfishes include over 640 species (Crandall and Buhay 2008), with the southeastern US being one of the epicenters of diversity. More than 360 species are represented in the US (Taylor et al. 2007). With 170 described species and 16 taxa listed as subspecies, the genus Procambarus contains the largest number of species of any genus of freshwater crayfish worldwide. The genus is currently divided into 15 subgenera that include: Acucauda, Astrocambarus, Capillicambarus, Girardiella, Hagenides, Leconticambarus, Lonnbergius, Mexicambarus, Ortmannicus, Paracambarus, Pennides, Procambarus, Scapulicambarus, Tennicambarus, and Villalobosus. The distinguishing feature of the genus Procambarus is the presence of four terminal elements of the male gonopods, which are the external reproductive organs found in arthropods. Representatives of the genus are found throughout much of eastern North America, ranging along the eastern seaboard and the coastal regions of the Gulf of Mexico, up the Mississippi River drainage as far as southern Wisconsin, and south through Texas and Mexico to Honduras (Longshaw and Stebbing 2016, p. 206).

Horton Hobbs, Jr., surveyed for and collected crayfishes in northwestern Florida in 1938. Four years later in 1942, Hobbs published the results of this survey, which included the first formal scientific description of the PCC as Procambarus econfinae, which was described from specimens collected at two sites along and near Highway 231. He designated the type locality as east of US 231 along Industrial Drive in Bay County, Panama City, Florida. From the time of Hobbs’s original collections in 1938 until 1986 there were no reports of the occurrence of this species (Keppner and Keppner 2014). The species was reported again in 1986 when specimens were collected from a roadside ditch draining into flatwoods habitat near the junction of County Road (CR) 390 and CR 389 in Bay County (Keppner and Keppner 2014).

The species again was found in 2000 at a site thought to be one of the original sites (type locality) on Industrial Drive (Keppner and Keppner 2000). Since 2000, there have been multiple papers published about the distribution of the species and its defined home range (Keppner and Keppner 2000, 2001, 2002, and 2004; Cook 2006; and FWC database 2012-2017). The species is considered to be a valid species (Taylor et al. 1996, 2007; Integrated Taxonomic Information System 2017) and meets the Endangered Species Act definition of a species (Breinholt and Moler 2016).

The currently accepted classification is (Integrated Taxonomic Information System 2017):

Phylum: Arthropoda

Subphylum: Crustacea

Class: Malacostraca

Order: Decapoda

Family: Cambaridae

Subfamily: Cambarinae

Genus: Procambarus

Subgenus: Procambarus (Leconticambarus)

Species: Procambarus econfinae (Hobbs 1942)

FWC’s draft management plan (2017) summarizes that eleven crayfish species are known from Bay County (Table 1.1) and eight, including the PCC, are found in the PCC range.

Table 2.1. Crayfish species found in Bay County, Florida (info slightly modified from FWC 2017).
Species
Found in PCC range
Uses same habitat as PCC
Comments
Cambarus diogenes No No Devil crayfish
Procambarus apalachicolae No Coastal flatwoods crayfish
Procambarus econfinae Yes, is PCC Yes, is PCC Panama City crayfish
Procambarus hubbelli Yes Jackknife crayfish, closely related and similar
Procambarus kilbyi partial possible encroachment Hatchet crayfish, closely related and similar
Procambarus latipleurum No Wingtail crayfish
Procambarus paeninsularus Yes Some overlap Peninsular crayfish, found in swamps and ponds
Procambarus pycnogonopodus Yes Yes Stud crayfish
Procambarus rogersi Yes Yes Seepage crayfish
Procambarus spiculifer Yes No White-tubercled crayfish, stream dweller
Procambarus versutus Yes No Sly crayfish, stream-dweller

Two of these (P. versutus and P. spiculifer) are strictly stream species, one (P. paeninsulanus) is more typically associated with swamps and overgrown ponds (not typical PCC habitat; see Life History and Habitat), and two (P. pycnogonopodus and P. rogersi) are found in the same habitat as the PCC and may co-occur with it. However, the PCC’s size, shape, and color pattern (Figure 2.1)

The Panama City crayfish (PCC)
Figure 2.1. The Panama City crayfish, Procambarus econfinae, light form male, dorsal view (Keppner and Keppner 2014). (Photo credit: Dr. Ed Keppner)

distinguish it from most of the other species of crayfish that occur within its range (Figure 2.2).

PCC and other crayfish distribution.
Figure 2.2. Range of PCC and other crayfish of similar appearance: P. apalachicolae and P. kilbyi in proximity to the PCC. (Map credit: Keppner and Keppner 2014).

The exceptions are two species (P. kilbyi and P. hubbelli) (Figures 2.3 and 2.4) that closely resemble the PCC and have been recently discovered in a small part of its range. The PCC is not known to hybridize with other species of crayfish.

Procambarus kilbyi
Figure 2.3. A photo of Procambarus kilbyi (from Keppner and Keppner 2014). (Photo credit: Dr. Ed Keppner).
Procambarus hubbelli
Figure 2.4. A photo of Procambarus hubbelli; the arrows indicate barbate chelae (Keppner and Keppner 2014). (Photo credit: Dr. Ed Keppner)