SCOTTO LARVAL DKVELOPMENT OF CUBAN STONE CRAB 



MaxilUpcd 3. Epi- and endopodites usually 

 naked. 



Sixth Zoeae (intercalated) 



Carapace length: 1.60 mm. 

 Number of specimens examined: 5. 



Carapace. Cephalothorax little inflated from 

 previous stage. Posterolateral border with 20-22 

 setae, other setation and armature unchanged. 



Abdomen. Pleopods elongate, one specimen with 

 setae partially extruded. First abdominal somite 

 with 11-14 dorsal setae. 



Telson. Similar in morphology to fifth stage. 



Antenniile (Figure 7A). Endopodal bud elongate 

 with up to 3 setae on distal end. Exopodite showing 

 evidence of five segments; aesthetasc number var- 

 iable, arranged in tiers: (progressing distally) 

 0,6-11,9-10,7-9,2 subterminal plus 5 terminal 

 (note: not all aesthetascs illustrated); unseg- 

 mented basal region swollen with 2 small setae 

 placed as shown. 



Antenna (Figure 7B). Endopodite surpassing 

 protopodal spinous process, showing evidence of 

 five segments; setation variable, or 1 on proxi- 

 mal segment, 0-3 on remaining four. Distal tip of 

 exopodal spine surpassing protopodal process but 

 attaining length of endopodal distal tip. Exopodal 

 spine now 0.5  length of exopodite; latter about 

 equal in length to protopodal process. 



Mandible (Figure 7C). Palp unsegmented, elon- 

 gate, with up to 3 distal setae. Molar process simi- 

 lar in form to fifth stage, 4 or 5 rounded to angular 

 prominences along margin of inner angle and 

 junction with incisor process; right molar process 

 with 2 or 3 prominences. 



Ma.xillule (Figure 7D). Proto- and endopodal se- 

 tation unchanged; basal endite with 11 spines plus 

 10-12 stout setae plus 2 laterally; coxal endite 

 with 6 strong plus 7 thinner setae plus 1 basally. 



Maxilla (Figure 7E). Endopodite unchanged; 

 basal endite lobes with usually 8 (8 or 9), 10 (8-10) 

 setae respectively; coxal endite setae usually 1 1,7. 

 Scaphognathite with 43-50 plumose setae on outer 



margin plus 2 small setae on lower surface of the 

 blade. 



Maxilliped 1 (Figure 6D). Coxopodite with 6 

 setae; basipodal setal formula similar to fifth stage 

 with 2-4 additional setae dispersed as illustrated; 

 endopodal setae 3,2,1,2-3,5 + 1; exopodite with 

 usually 1 1 ( 11 or 12) plus 1 lateral natatory setae. 



Maxilliped 2 (Figure 6E). Coxo- and basipodal 

 setation unchanged. 1 and 4 setae, respectively; 

 endopodal setae 0,1,5; exopodite with 12 plus 2 

 natatory setae. 



Maxilliped 3 (Figure 6F). Exopodite two- 

 segmented with S setae on distal segment; unseg- 

 mented endopodite unchanged from previous 

 stage; epipodite with up to 6 setae. 



Color. Entire zoea much lighter orange-rose 

 than in previous stage. Eyestalks each with one 

 brown-orange chromatophore anteriorly. Ros- 

 trum pale rose. Proximal segment of exopodites of 

 maxillipeds 1 and 2 now yellow. Brown-orange 

 postcardiac chromatophores, present in first five 

 zoeal stage, now absent. 



Megalopae 



Carapace length '-^ width: 1.50 ^ 1.31 mm. 



Number of specimens examined: 10. 



Remarks: Megalopae (VI) molting from stage 

 VI zoeae differed only slightly from those 

 megalopae (V) molting from stage V zoeae. 

 These differences are noted under the appro- 

 priate headings. 



Carapace (Figure 8A). Cephalothorax subquad- 

 rate overall, sparsely covered with hairs as shown; 

 posterior and posterolateral border with up to 60 

 setae. Frontal region rectangular, rostrum 

 strongly deflexed, nearly vertical, bluntly rounded 

 with distinct median cleft, slightly expanded lat- 

 erally to meet bluntly angular interorbital promi- 

 nence. Orbit excavated, nearly rectangular; eyes 

 large, eyestalks with 5 anterior setae. 



Abdomen (Figures 8A, 9A), Pleurae 1 through 5 

 with lobes at posteroventral angles, that of somite 

 6 subquadrate. First abdominal somite with up to 

 32 setae arranged in a transverse row, somites 2 

 through 6 sparsely covered with setae. 



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