Alpheidae Rafinesque 1815
Creators: name: Wicksten, Mary K.
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Alpheidae

description: Key to species of family Alpheidae  1. Triangular movable plate articulated at posterolateral angle of abdominal somite 6 lateral to base of uropod.............. 2  
– No triangular movable plate articulated at posterolateral angle of abdominal somite 6 lateral to base of uropod............ 9  
 2. Rostrum prominent, orbital hoods armed with teeth........................................ Alpheopsis equidactylus   
– Rostrum absent, front without teeth....................................................................... 3  
3. Dactyls of preopods 2–5 slender, simple.................................................................... 4  
– Dactyls of pereopods 2–5 stout, bifid...................................................................... 6  
 4. Chela of pereopod 1 with fingers longer than palm. Large male with gaping fingers of chelipeds...... Betaeuslongidactylus   
– Chela of pereopod 1 with fingers not longer than palm. Large male without gaping fingers............................ 5  
 5. Blade of scaphocerite broad distally. Fixed finger of pereopod 1 decreasing in width evenly to sharp curved apex................................................................................................ Betaeus harrimani   
 – Blade of scaphocerite narrow distally. Fixed finger of pereopod 1 truncate distal to sharp curved apex... Betaeus ensenadensis   
 6. Front curved, not emarginate. Symbiotic with sea urchins (Strongylocentrotus spp.)................. Betaeus macginitieae   
– Front emarginate. Symbiotic with abalone or crabs or free-living................................................ 7  
 7. Emargination of front shallow. Telson with posterolateral spines small or missing. Symbiotic with abalones (Haliotis spp.)......................................................................................... Betaeus harfordi   
– Emargination of front deep. Telson with posterolateral spines well developed. Not symbiotic with abalones.............. 8  
 8. Peduncle of antennule less than 0.5 carapace length. Merus of cheliped with lower inner ridge with long bristles, upper ridge ending in sharp tooth; chela 3 times as long as wide, fingers subequal to palm......................... Betaeus gracilis   
 – Peduncle of antennule subequal to carapace length. Merus of cheliped with lower inner ridge usually tuberculate, upper ridge with tuft of hair; chela 2 times as long as wide, fingers longer than palm.............................. Betaeus setosus   
 9. Eye fully exposed dorsally........................................................... Automatedolichognatha   
– Eye covered by carapace............................................................................... 10  
 10. Pereopods without epipods. Dactyls of pereopods 3–5 bifid.................................. Synalpheus lockingtoni   
– Pereopods with epipods. Dactyls of pereopods 3–5 with simple apices.......................................... 11  
 11. Dactyl of major chela closing horizontally. Merus of pereopod 3 with prominent inferior tooth.......... Alpheus clamator   
– Dactyl of major chela closing vertically. Merus of pereopod 3 without prominent inferior tooth...................... 12  
 12. Orbital hoods with teeth. Minor chela with prominent tooth posterior to movable finger, movable finger flattened (lamellate)....................................................................................... Alpheusbellimanus   
 – Orbital hoods without teeth. Minor chela without prominent tooth posterior to movable finger, movable finger not flattened..................................................................................... Alpheus californiensis
description: Published as part of Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, pp. 1-307 in Zootaxa 3371 on page 58