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Mediterranean invasive species factsheet

CRUSTACEANS

Reproduction Common name: Speckled shrimp

9-12 teeth
Long spine
(in male)
identification

Scientific Name:
Metapenaeus monoceros
Picture

Key identifying features
Brief history
The body is covered with short hairs and is pale grey
speckled with dark brown spots. The antennae are
orange-red. The maximum length of adult males is 15
Purple blue
cm and of females 20 cm. The rostrum has 9–12
teeth on the upper margin. Males are easily
distinguished from other shrimps in bearing a
prominent curved spine on their fifth walking leg. The
first and third walking legs bear a basal spine.

Field identification signs and habitat
The speckled shrimp is found to a depth of 170 m,
commonly 10–30 m, on sandy or sandy-mud
bottoms.

Reproduction
Spawning occurs twice a year, with the first peak in
May–June and the second in October–November in
Tunisia, and in May and July–October in Egypt. In
Tunisia, the size for males to reach sexual maturity is
7.6 cm and for females 12.2 cm, although the
smallest mature specimen found in Egyptian waters Metapenaeus monoceros. Photo: B. Yokes
was 9.5 cm. The larvae can be transported over long
distances, a possible means of new introductions.

Metapenaeus monoceros. Photo: Olfa Ben Abdallah. Metapenaeus monoceros. Photos: B. Yokes

Monitoring Marine Invasive Species in Mediterranean MPAs: A strategy and practical guide for managers 83