New England Marine Invader ID Card Amphipods and Shrimp

Gretchen Carlson Adrienne Pappal Caprella mutica Palaemon elegans Japanese Skeleton Shrimp European Rock Shrimp • Mottled red body with a ridge of small spines along back • Mostly translucent body with dark red-brown bands, neon blue • Males can be over 2 inches long, first two body segments are claws, and orange/blue bands on legs smooth and very long, giving the appearance of a long bent neck • Can be up to 2.5 inches long • Females are smaller with a brood • Distinct, shovel-shaped rostrum has 7 pouch with red spots to 9 teeth across the top • Native to the north Pacific coasts of • Occurs near docks, in tide pools, and Asia, now common throughout in salt marsh creeks New England, especially on • Found from Connecticut to Maine,

docks and pilings Andrew Martinez range is expanding Arjan Gittenberger Skeleton shrimp are a large family of caprellid amphipods with a First observed in New England in 2010, P. elegans belongs to the long body, large front claws, long antennae, and hind legs grass shrimp family, which includes both native and non-native that cling to surfaces (see photo above of C. mutica clinging to a species. The body includes a long pair of antennae, a serrated colonial tunicate). Caprellids are o en highly animated and can be rostrum, and five pairs of legs. The first two pairs of legs have small, seen “waving” back and forth in large groups. slender claws.

Marine Invader Monitoring and MASSACHUSETTS OFFICE OF Information Collaborative (MIMIC) Established Invaders COASTAL ZONE MANAGEMENT Similar Species Family Caprellidae Skeleton Shrimp • Aeginina longicornis (illustration below) is the only species with males as big as C. mutica, but the first two body segments of A. longicornis are much smaller and spines are present along the entire back Adrienne Pappal Cristina Kennedy Palaemon spp. Palaemon macrodactylus Grass Shrimp Asian Shrimp (non-native) • Transparent with muted coloration • Dark, muted body color with reddish spots and and banding orange-beige bands on claws and legs Salem Sound Coastwatch • New England species include P. • Can have a whitish stripe along the back pugio, P. vulgaris, and P. intermedius • Usually 10 to13 teeth across top of rostrum with double rows of setae • Caprella penantis (photo below) is much Rostrum Identification (fine hairs) along bottom smaller than C. mutica, has short body P. elegans segments like A. longicornis but with no • Native to the Northwest spines along the back Pacific, first observed in P. macrodactylus Long Island Sound in 2001, now found north P. vulgaris (native) to New Hampshire The shape of the rostrum and arrangement of teeth along it may • Difficult to tell apart from help to distinguish palaemonid shrimp species in the field, native shrimp in the field particularly for large individuals. A microscopeAdrienne Pappal may be needed Agnes Mittermayr for definitive ID. Species are native unless otherwise noted.