Alpheid Shrimp, X: Fiji, Tonga, Samoa- — Banner and Banner 
173 
be shown in a later paper to be merely a female 
of A. idiocheles. 
4. A. microscaphis (Banner). This species 
can be easily characterized by the extreme 
reduction of the scaphocerite, reaching only 
to or slightly past the end of the first antennular 
article, and by the dactylus of the large chela, 
which has the form of a two-headed hammer. 
In summation, the following species have 
been retained: 
A. obesomanus Dana. Synonyms: A. lutini 
Coutiere, A. species 2 Banner 
A. microstylus (Bate). Synonym: A. micro- 
stylus var. ? de Man 
A. malleo digitus (Bate). Synonyms: A. 
malleo digitus var. gracilicctrpus de Man, 
A . phyrgimus Coutiere, A. persicus Mobil! 
A. danae Coutiere 
A. samoa (sp. nov.) 
A. nobili nom. nov. Synonym: A. species 
Nobili 
KEY TO THE SPECIES OF THE OBESOMANUS GROUP 
1 . Outer uropod with articulation 2 
Outer uropod without articulation . 9 
2(1). Dactylus of third legs simple 3 
Dactylus of the third legs biunguiculate 8 
3(2). Second carpal article of second legs more than twice as long as first 4 
Second carpal article less than twice as long as first, usually less than 1.5 times as long 5 
4(3). Squamous portion of scaphocerite reaching only to middle of second antennular 
article A. obesomanus Dana 
Squamous portion of scaphocerite reaching to near end of third antennular article 
A. micro stylus (Bate) 
5(3). Scaphocerite and carpocerite reaching to near end of third antennular article 
A. nobili nom. nov. 
Scaphocerite reduced, with tip reaching only to middle of second antennular article 
or less; carpocerite various but usually reduced 6 
6(5). Scaphocerite reaching to near middle of second antennular article 7 
Scaphocerite not reaching to end of first antennular article A. samoa sp. nov. 
7(6). Carpocerite markedly longer than scaphocerite, reaching at least to end of second 
antennular article A. malleo digitus (Bate) 
Carpocerite subequal to scaphocerite, reaching only to middle of second antennular 
article A, danae Coutiere 
8(2). Large chela with crests and grooves, like those found in Megacheles group; without 
rostrum . A. perplexus Banner 
Large chela smooth, without crests and grooves; with rostrum A. chamorro Banner 
9(1). Without rostrum (Caribbean species).... A. rathbunae Schmitt 
With rostrum 10 
10(9). Scaphocerite reaching to middle of second antennular article; dactylus of large 
chela without superior projection A. idiocheles Coutiere 
Scaphocerite reaching only to near end of first antennular article; dactylus of large chela 
with characteristic double-headed hammer shape of Obesomanus group 
A. microscaphis (Banner) 
