MARESTE GAMMARIDEAN AMPHIPODA 119 



Paramphithoe Acanthonotozoma 



Mouthparts bluntly bundled conically bundled 



Mandible stout substyliform 



Mandibular molar large, ridged obsolescent, conical 



Maxillae stout substyliform 



Gnathopods small, subchelate styliform 



Intergradations of these conditions occur in the genera of both 

 families. If the sea yields more genera similar to Bathypanoploea, the 

 fusion of the Paramphithoidae and Acanthonotozomatidae may be 

 required. 



Acanthonotozomella oatesi K. H. Barnard (1930) is transferred to 

 Acanthonotozomoides. 



Key to the Genera of Acanthonotozomatidae 



1. Palp of maxUla 1 uniarticulate (fig. 56d) 2 



Palp of maxUla 1 biarticulate (fig. 56c) 4 



2. Gnathopod 2 slender and chelate (fig. 56o) 3 



Gnathopod 2 stout and subchelate (fig. 56p) Odius 



3. Palp article 2 of maxUliped strongly produced medially along article 3 



(fig. 56i) Pariphimedia 



Palp article 2 of maxilliped not produced (fig. 5&h) . . Paranchiphimedia 



4. Palp of maxilla 1 very short, not reaching end of outer plate (fig. 56d) . . 5 

 Palp of maxilla 1 reaching end of outer plate (fig. 56c) 7 



5. Gnathopods 1 and 2 simple (figs. 5Qk,n) Panoploeopsis 



Gnathopod 1 minutely chelate (figs. 56i, m), gnathopod 2 not simple . . 6 



6. Palp article 2 of maxilliped produced along inside of third (fig. 56i), lower 



lip usually incised (fig. 56a) Panoploea 



Palp artile 2 of maxilliped not produced along inside of third (fig. 56^), 

 lower lip not incised (fig. 566) Anchiphimedia 



7. Mandible tapering to a smooth, symmetrical, scoop-shaped apex (fig. 55gr) . 8 

 Mandible not as above (e.g., fig. 55fc) 9 



8. Upper lip rounded, not incised (fig. 55c); lower lip not incised (fig. 566). 



Labriphimedia 

 Upper lip quadrangular, incised (fig. 55d) ; lower lip incised (fig. 56o) . 



Maoriphimedia 



9. Gnathopod 1 simple (fig. 56A;) 10 



Gnathopod 1 chelate (fig. 560 13 



10. Telson entire, rounded (fig. 56g) Acanthonotozomoides 



Telson distally notched or emarginate (figs. 56r,s) 11 



11. Gnathopod 1 feeble, very slender, gnathopod 2 stouter than 1. 



Acanthonotozoma 

 Gnathopods 1 and 2 similar to each other, well developed 12 



12. Palp of maxilliped shorter than outer plate; mandible pointed (fig. 55Z). 



Bathypanoploea 

 Palp of maxilliped longer than outer plate; mandible distally broad (fig. 55A;). 



Acanthonotozomella 



13. Cutting edge of mandible drawn out in a long, needle-like apex (fig. 55j). 



Parapanoploea 



