Distribution, Habitat, and Life History Aspects of the Dwarf Crayfishes of the Genus Cambarellus (Decapoda: Cambaridae) in Arkansas

The dwarf crayfishes of the genus Cambarellus are represented in Arkansas by only 2 species: Cambarellus (Pandicambarus) puer (Hobbs) and C. (P.) shufeldtii (Faxon). Both species are quite small and uncommonly encountered in the state. Between 1972 and 2018, we made 368 crayfish collections throughout the 75 counties of Arkansas. A total of 34 collections (our collections, plus museum specimens), and those previously collected by Reimer (1963) yielded a total of 304 specimens of C. puer and 12 collections of C. shufeldtii returned 54 specimens of C. shufeldtiii. Herein, we document these 2 dwarf crayfishes from primarily the Coastal Plain and Mississippi Alluvial Plain physiographic provinces of Arkansas. Cambarellus puer is documented from 24 counties whereas C. shufeldtii was recorded from only 12 counties. With regard to conservation status, both C. puer and C. shufeldtii should be considered as “Currently Stable” due to their widespread distribution and general abundance in Arkansas

Distribution, Habitat, and Life History Aspects of the Shrimp Crayfish, Faxonius lancifer (Hagen) (Decapoda: Cambaridae) in Arkansas

The Shrimp Crayfish, Faxonius (formerly Orconectes) lancifer (Hagen) is an uncommon, although widespread, crayfish in Arkansas. This species is herein documented from 19 counties of the Gulf Coastal Plain physiographic region. Between 1974 and 2017, we made 344 collections throughout the 75 counties of Arkansas, of which 22 (6%) yielded 163 specimens of F. lancifer. Thus, from these collections, plus 10 unpublished collections of Reimer (1963), and one collection from G.L. Harp, a total of 34 collections of F. lancifer are now known from the state. Faxonius lancifer ranged from uncommon (1 specimen) to locally abundant (39 specimens) at these collecting localities. With regard to conservation status, F. lancifer should be considered as Currently Stable due to its widespread distribution and general abundance in Arkansas

Additional Records of Acanthocephalan Parasites from Arkansas Fishes, with New Records from Missouri Fishes

Over the last decade, our research consortium has provided information on acanthocephalan parasites of Arkansas vertebrates, including records from some of the state’s fishes. Here, we continue to provide data on new geographic and new host records of acanthocephalans from Arkansas fishes. In addition, for the first time, we report records of acanthocephalans for some Missouri fishes. We document 2 new state records as well as 10 new host records for some fish acanthocephalans

An Annotated Checklist of the Crayfishes (Decapoda: Cambaridae) of Arkansas

Prior to the present study, 56 species with 3 additional subspecies for a total of 59 different taxa of crayfishes were recognized from Arkansas. We add a single species (Carmel Crayfish, Fallicambarus schusteri) to that list, subtract a documented synonym (Procambarus ferrugenius = Procambarus liberorum), update the classification to better reflect recent phylogenetic insights, and provide an updated annotated checklist of the 59 crayfish taxa of presently known from the state. There are 8 endemic species in Arkansas, including the Bayou Bodcau Crayfish (Bouchardina robisoni), Boston Mountains Crayfish (Cambarus causeyi), Hell Creek Cave Crayfish (C. zophonastes), Jefferson County Crayfish (Creaserinus gilpini), Ouachita Burrowing Crayfish (Fallicambarus harpi), Slenderwrist Burrowing Crayfish (F. petilicarpus), Saline Burrowing Crayfish (F. strawni), and Redspotted Stream Crayfish (Faxonius acares). There are also 2 federally endangered species, the Benton County Cave Crayfish (Cambarus aculabrum) and the Hell Creek Cave Crayfish (C. zophonastes) that inhabit Arkansas karst habitat. We expect that additional species will be included in the list with further DNA analyses

Arkansas Endemic Flora and Fauna An Update with 13 Additional Species

Arkansas supports a diverse variety of endemic biota with most found in the Interior Highlands (Ozarks and Ouachitas) of the state. Since 1988, several compilations have updated the number of endemics known while some former endemic species have been found in other states and subsequently removed from the state list. Here, update to the list by adding 13 taxa, several of which are fish parasites, making a grand total of 139 current endemic species in Arkansas

Geographic Distribution and Life History Aspects of the Freshwater Shrimps, Macrobranchium ohione and Palaemonetes kadiakensis (Decapoda: Palaemonidae), in Arkansas

Two species of shrimps occur in Arkansas; they include the Ohio shrimp, Macrobrachium ohione (Smith) and the Mississippi grass shrimp, Palaemonetes kadiakensis Rathbun. The present survey is based on collections made between 1974 and 2008 with additional supplemental data from museum specimens to document the overall distribution of the 2 species. Our survey found a total of only 42 specimens of M. ohione from 6 localities (2 counties) in Arkansas, all taken from the Mississippi River. Specimens were seined over sandy substrates in 0.6-0.9 m of water without vegetation. A 1914 museum collection of 5 individual M. ohione is the only known occurrence of M. ohione from Phillips County. All other specimens were taken between 1974-1975 near the US 82 bridge (Chicot County). It appears that M. ohione is a relatively rare shrimp in Arkansas. Since specimens were documented from a single drainage system (Mississippi River) in only 2 counties, we recommend a “threatened” conservation status of M. ohione in Arkansas because of this restricted distributional range. However, P. kadiakensis is relatively abundant in Arkansas. This shrimp had previously been reported from 10 counties of the state. Over 3,400 specimens of P. kadiakensis were documented during this study from various sites in 49 counties and most were released upon capture. Grass shrimp were commonly found in sluggish backwater regions of streams especially preferring heavily vegetated lentic areas of pool regions. Mississippi grass shrimp have remained abundant and widespread in occurrence for the past 35 years. The Nature Conservancy lists populations of P. kadiakensis as secure (G5) in rounded global status. Indeed, Mississippi grass shrimp populations in Arkansas are also secure and in no need of special protection