Taxonomy of Shellfish

5.2.4. Metapenaeus monoceros

Unit 5 -Key to important species the family Penaeidae

5.2.4. Metapenaeus monoceros - Speckled shrimp

• Almost entire body pubescent; or in East Africa (except the Red Sea), pubescence restricted to dorsal part of carapace and abdominal patches;
• Rostrum armed with 9 to 12 teeth along entire dorsal margin, straight, reaching as far as, or beyond, tip of antennular peduncle;
• Postrostral crest reaching posterior margin of carapace or nearly so adrostral crest ending behind second rostral tooth, adrostral groove behind epigastric tooth;
  
• Branchiocardiac ridge sinuous, reaching posterior extension of hepatic spine;
• Telson armed only with spinules;
• A small ischial spine on first pereopod.
• In adult males, merus of fifth pereopod with a proximal notch followed by a long, inwardly curved spiniform process and a row of tubercles;
  
• Distomedian projections of petasma convoluted, greatly swollen, bulbiform, directed anterolaterally and concealing distolateral projections in ventral view.
• In females, anterior plate of thelycum long and deeply grooved; lateral plates with strongly raised margins forming 2 longitudinal crests.