JACKSON ET AL.: KEY TO GENERA OF PENAEID LARVAE 



Figure 17. — Telson shapes of protozoeae. Protozoea II - (a) Penaeus, (b) Metapenaeus, (c) Trachypenaeus, (d) Meta- 

 penaeopsis, (e) Atypopenaeus, (f) Parapenaeopsis. Protozoea III - (g) Penaeus, (h) Metapenaeus, (i) Trachypenaeus, (j) 

 Metapenaeopsis, (k) Atypopenaeus, (.1) Parapenaeopsis. Scale = 0.1 mm. 



Uropods present (protozoea III) 14 



Protozoea II 



10(9) A single pair of supraorbital spines 



(Fig. 2a) 11 



Two paii-s of supraorbital spines (Fig. 

 9a) 12 



11(10) Telson wedge-shaped, with no distinct 



angle in lateral border (Fig. 17e) 



Atypopenaeus 



Telson with a distinct angle in lateral 

 border (Fig. 17b) Metapenaeus 



12(10) Inner pair of supraorbital spines fila- 

 mentous and less than half as long as 



outer pair (Fig. 18) Metapenaeus^ 



Inner pair of supraorbital spines 

 robust, similar in size to outer pair 

 (Fig. 9a) 13 



13(12) Body length greater than 1.6 mm .... 



Parapenaeus 



Body length less than 1.6 mm 



Metapenaeopsis 



^M. ensis orM. monoceros. 



Ill 



