Taxonomy of Shellfish

Unit 5 -Key to important species the family Penaeidae

5.1.4. Penaeus monodon - Giant tiger prawn

• No lateral keels on carapace;
• Cutting portion of mandible short and massive;
• Rostrum toothed on dorsal, as well as on ventral margin, rostrum armed with 7 or 8 teeth on dorsal and 3 or 4 (rarely 2) teeth on ventral margin,
• Adrostral crest and groove extending as far as or slightly ahead, of epigastric tooth;
  
• Postrostral crest well developed, almost reaching posterior margin of carapace, with or without a feeble median groove;
  
• Antennal crest very prominent, ending above middle of hepatic crest;
  
• Gastro-orbital crest extending over posterior half, or less, of distance between hepatic spine and orbital margin;
  
• Hepatic crest straight, almost horizontal, distinctly separated from base of antennal crest;
• Fifth pereopod without exopod.
• Petasma (in males) with distomedian projections slightly overhanging distal margin of costae;
  
• Ventral costae generally unarmed, sometimes minutely serrate at tip;
  
• Outer surface of lateral lobes generally unarmed; inner surface of lateral lobes armed with spinules.
• Thelycum (in females) with lateral plates, their median margin sometimes forming tumid lips; anterior process concave, rounded distally; posterior process subtriangular, partly inserted between thelycal plates.