FISHERY BULLETIN VOL 77. NO :; 



a dorsolateral spine not found in M. nodifrons. 

 Additionally, in the first zoeal stage several differ- 

 ences (Table 2i include: antennular aesthetasc 

 number, maxillulary coxal endite setation. and 

 segmentation of the exopodites of the first and 

 second maxillipeds. Setation differences in other 

 stages are relatively minor (Table 3), and include: 

 setation of the first maxilliped, in zoeal stage 2; 

 setation of the maxillary basal endite and endopo- 

 dite of the second maxilliped, in zoeal stage 3; and 

 setation of the maxillulary basal endite, in zoeal 

 stage 4. 



Setation on the larval appendages of Af. nodi- 

 frons becomes particularly variable in the fifth 

 stage: because of this, distinguishmg characters 

 between M . nodifrons and.M. tnercenaria in this 

 stage are not discussed. However, in M . nodifrons 

 there are several differences between ultimate 

 fifth stage zoeae [ZV(u)| that molt directly to 

 megalopae and penultimate fifth stage zoeae 

 [ZV(p)l that molt to sixth stage. These include 



(Table 4): coxopodal setation of the first maxil- 

 liped, antennular aesthetasc number, exopodal se- 

 tation of the third maxilliped, and setation on the 

 first abdominal somite. In addition, the antennal 

 endopodite bud reaches the tip of the protopodite 

 in ZViu); in ZV(p) it is less elongate, reaching only 

 to distal end of protopodite process spinules. 



Differences between the sixth zoeal stages of M. 

 nodifrons and M. mercenaria concern setation ol' 

 the maxillary scaphognathite and first maxil- 

 lipedal basipodite (Table 5). Other distinguishing 

 characters include evidence of antennular exopo- 

 dite and antennal endopodite segmentation, also 

 observed in Callinectes sapidus (Costlow and 

 Bookhout 1959). 



Kurata"* described the complete larval develop- 

 ment, including the megalopal stage, of M. mcr- 



■^Kurata. H. 1970. Part IH. Larvae of decapod Crustacea of 

 Georgia. In Studies on the life histories of decapod Crustacea of 

 Georgia. UnpubL manuscr.. 274 p. University of Georgia, 

 Marine Institute. Sapelo Island. GA 31327. 



Table 2. — Taxonomically important first zoeal characters in three species o{ Menippe ? 



Character 



M rumphii 

 (Prasad and Tampi 1957) 



M mercenaria 

 (Porter 1960) 



Carapace 

 Rostrum 

 Dorsal spine 

 Lateral spine 



Margin 



Antennule 



Exopodite 

 Antenna 



Exopodite 



Mandible 



Maxillule 

 Endopodite 

 Basa! endite 

 Coxal endite 



Maxilla 

 Endopodite 

 Basal endite 

 Coxal endite 

 Scaphognathite 



Maxilliped 1 

 Coxopodite 

 Basipodite 

 Endopodite 

 Exopodite 



Maxilliped 2 

 Coxopodite 

 Basipodite 



Endopodite 

 Exopodite 



Straight, unarmed 

 Posteriorly curved 

 Venlrally curved 

 Unarmed 

 Conical rod 



4 aesthetascs 

 Exopodite ^4 protopodite 

 Tapered, long subtermmal spine 



Scoop-shaped, incisor and molar 

 processes indistinctly dentate 

 and serrate, no palp 



Two-segmented 1 , 4 seiae 



5 hirsute setae 

 7 hirsute setae 



Bilobed 3,3 setae 

 Biiobed 5,4 setae 

 Bilobed 5,4 setae 

 4 plumose setae, distal plumose 

 process 



1 seta 



10 setae. 2,2,3.3. 

 Five-segmented 3.2.1,2.5 

 Two-segmented. 4 natatory setae 



Naked 



4 setae 



Three- segmented 1,4 setae 



Two-segmented, 4 natatory setae 



Somites 2 to 5 with 2 posterodor- 



sal setae, somite 4 without 

 spines in all stages 



Straight, unarmed 

 Posteriorly curved 

 Ventrally curved 

 Unarmed 

 Conical rod 

 4 aesthetascs 

 Exopodite - protopodite 

 Tapered, single spine 



Cutting edge serrate, no palp 



Two-segmented 1, 4 setae 



5 hirsute setae 



6 hirsute setae 



Bitid 3,3 setae 

 Bifid 5,4 setae 

 Bitid 5.4 setae 



4 plumose setae, posterior plumose 

 process 



1 seta 

 6 setae 



Five-segmented 2,2.1,2,4 

 4 natatory setae 



Not given 

 Few setae 



Three-segmented 0.2.4 setae 

 4 natatory setae 



Somites 2 to 4 with a pair of short 

 hairs; somite 4 without spines 



Straight, unarmed 



Posteriorly curved 



Ventrally curved 



Unarmed 



Conical rod 



6 aesthetascs 



Ratio not given 



Tapered. 1 long heavy spine 



Lateral and posterior cutting edge 

 indistinct teeth, no palp 



Two-segmented 1 , 4 setae 



5 stout hairy setae 



6 stout hairy setae 



Bilobed 3,3 setae 

 Bilobed 5 4 setae 

 Bilobed 5.4 setae 

 4 plumose setae, distal plumose 

 process 



Not given 

 10 setae 



Five-segmented 2.2.1.2.5 

 Partially bisegmenled. 4 

 natatory setae 



Not given 

 4 setae 



Three-segmented 0,1,4 setae 

 Partially bisegmenled. 

 4 natatory setae 



Somites 1 to 5 with 2 posterodor- 

 sal setae, somite 4 with pair 

 of dorsolateral spines m all 

 stages 



'Characters taken from authors descriptions and illustrations 



378 



