250 



ii. Posterior border of carapace smooth : — 



a. Eyes movable : frontal border of carapace 



smooth : — 



a. Chelipeds of male about as long as the 

 body : transverse carinse of 2nd-4th 

 abdominal terga smooth ... M. stylirostris. 



P. Chelipeds of male much longer than 

 the body : transverse carina? of 2nd 

 and 3rd abdominal terga spinose 

 near the middle line ... ... M. wardeni. 



b. Eyes immovable: frontal border of carapace 



with a large spine on either side behind the 



base of the antenna ... ... ... M. goodridgii. 



IV. No epipodites on chelipeds or legs : the chelipeds very little longer than 



the legs and much shorter than the body ... ... ... M. moresbyi. 



Key to the species included in Group II (Galathodes). 



I. Epipodites are present on the chelipeds : anterior border of 2nd-4th abdo- 

 minal terga spiniferous : — 



1. Posterior border of carapace spiniferous ... ... M. regia. 



2. Posterior border of carapace smooth ... ... ... If. trimna. 



II. No epipodites on chelipeds or legs : — 



1. Anterior border of 2nd and 3rd abdominal terga and posterior 



border of carapace spiniferous ... ... ... M. posidonia. 



2. Abdominal terga without spines : — 



i. Posterior border cf carapace sharply serrulate ... M. trachypus. 

 ii. Posterior border of carapace smooth : — 



a. A pair of large spines on the gastric region ... 21. trifida. 



b. No spines on dorsum of carapace ... ... M. tridentata. 



I. 



II. 



Key to the species included in Group III (Orophorhynchus). 



The lateral borders of the carapace are non-spinose : the eyestalks are 

 broadened and vertically compressed so that the eyes are distinctly 

 lateral : — 



1. Epipodites are present on the chelipeds : integument tomentose : 



abdominal terga unarmed ... ... ... M. edivardsi. 



2. No epipodites on chelipeds or legs : integument coarsely granu- 



lar : 2nd-4th abdominal terga with a coarse median spine ... M. granosa. 



The lateral borders of the carapace are spinose : the eyestalks are not 

 sublaminar: — 



1. Epipodites are present on the chelipeds: — 



i. Both the inner and the outer borders of the eyestalk are 



prolonged beyond the eye as spines ... ... M. ciliata. 



ii. Only the inner border of the k eyestalk is prolonged 



beyond the eye as a spine ... ... ... M. subsquamosa. 



