Red Snapping Shrimp
Alpheus species 9
Red Snapping Shrimp
Alpheus species 9
undescribed
Description
This is a long-legged shrimp that moves with its legs wide apart giving it a somewhat spider-like action. Very active, usually working in pairs. The colour is dark red overall but often has a grey-dusty look, even in clean coarse sand. There is some variation in colour with some individuals being more pink than red.
Carapace: This body has a stocky bullet-shaped look with the first abdominal segments as wide as the cylindrical carapace. The dorsum of the carapace is red-grey becoming a brighter dark red laterally, The side of the carapace is brighter dark red with a faint epaulette mark. There are lighter grey dendritic patches randomly distributed on the dorsum, making the shrimp look dusty even when it is clean.
The abdomen is matt grey-red with a suggestion of fine longitudinal striations and a more obvious pale line laterally.
The legs are red with paler joints.
The rostrum is red, as are the antennae. Antennules are darker red than antennae.
The pincers are dark red and vary greatly in size.
Identifying Features
Similar Shrimps
Distinctive shrimp, all red, spider-like and very active. Very different from the small secretive red pyjama shrimp.
Nomenclature
Undescribed species. No scientific name.
Ryanskiy (2016) p8. has images of a similar-looking shrimp and gives the name Alpheus sp common name Cherry Snapping Shrimp. Length up to 5 cm. Distribution Western Pacific – Indonesia (Lembeh Straits).
Hayashi & Shiratori (2003) Alpheus species 5 from Japan.
Ecology
HABITAT
Preferred substrate Medium to coarse clean sand
Depth range 10 to 20 metres
Proximity to reef In general they live well away from the reef but in places where conditions away from the reef are too silty and the only zone of suitable substrate is along the fringing reef the pair settle there.
NATURAL HISTORY
Very active shrimp, usually working in pairs. We have found this shrimp moderately common in clear water on the white sand bottom of current swept channels with occasional rocky outcrops. They often dig long trenches in the sand.
Although they tolerate strong tidal currents they can be found in calm conditions. The nature of the substrate is the determining factor.
They associate with at least six species of shrimpgoby but Amblyeleotris gymnocephala is the typical partner.
Jaafar (2014) provides beautiful photographic evidence of the Red Shrimp, working as a cleaner shrimp for its partner, a Ventral-barred Shrimpgoby, Cryptocentrus sericus. This is normal behaviour for Alpheid partner shrimps and has been studied in aquarium conditions for other species. It normally takes place in the burrow but we and others have occasionally filmed it in the field. It is rarely observed behaviour possibly this is because it is risky for both partners in a trance while exposed at the burrow entrance.
Distribution
Published distribution:
Western Pacific; Indonesia, Ryanskiy (2016).
Our records:
Australia; Fitzroy Island, Low Isles.
Solomon Islands; Ghizo, Santa Isabel Island.
Indonesia; Kabuii Bay in Waigeo Island.
Associated Goby species
Associated Shrimpgobies (six species)
Amblyeleotris gymnocephala, Mask Shrimpgoby
Amblyeleotris periophthalma, Broadbanded Shrimpgoby
Amblyeleotris rubrimarginata, Redmargin Shrimpgoby (video)
Amblyeleotris steinitzi, Steinitz’s Shrimpgoby
Cryptocentrus cinctus, Yellow Shrimpgoby
Cryptocentrus sericus, Ventral-barred Shrimpgoby
Videos
Redmargin Shrimpgoby (video) (to be added)