(Goës, 1864)
Description
— Generic features. General form slender and delicate. Eyes well developed, short, reniform and flattened dorso-ventrally, pigment brilliant red in living specimens. Antennal scale with outer margin entire or coarsely serrate, without setae, terminating in a strong spine beyond, no distal suture. Last four pairs of pleopods of the male well developed and biramous, first pair with endopod reduced to a single segment. Uropod, exopod and endopod undivided, setose alle round; no spines on outr margin of exopod; inner margin of endopod may be minutely serrated. Telson very short, entire, trapeziform, lateral margins naked; apex truncate, armed with 2 pairs of strong spines; no median plumose setae.
— Species. Body with cephalothorax distinctly wider than the abdomen. Carapace with anterior margin produced between the eyes into a short tongue-like rostrum.
Antennal scale about four times as long as broad, considerably longer than antennular peduncle, outer margin entire, without serrations, terminating in a strong spine; apex extending to about twice length of terminal spine.
Eyes very large and set close together, very flattened dorso-ventrally, broader than long, cornea kidney-shaped, stalk tapering rapidly proximally, pigment a particularly brilliant carmine red. Each facet in the retina is surrounded by a chalk-white margin which accentuates the brilliance of the red pigment.
First thoracic limb of normal type but with extremely delicate nail surrounded by fine setae. Second thoracic limb well developed, carpus markedly arcuate, equal in length to the propodus and dactylus together. Third to the eighth thoracic limbs shorter than in E. serrata and E. abyssorum; eighth endopod when stretched backwards, only reaches the anterior margin of the sixth abdominal somite.
Telson broader than long, lateral margins straight, posterior margin slightly convex, middlepair of spines twice as long as the outer in both sexes.
Uropods with exopod more than one-sixth longer than endopod, the latter slender, tapering distally, with 6-7 delicate plumose setae set a little way in from the outer margin, inner margins without serrulations.
Colour
This species is the most beautifully coloured of all species of the North Sea. A peculiar opaque white pigment is scattered all over the body and telson in the form of white spots and throws up the particularly brilliant orange red patch on the dorsal surface of the carapace and its lateral margins and the markings on the abdomen. The pigment spots on the ventral surface are a clear bright yellow.
Size
Adult up to 9-11 mm long.
Depth range
Hyperbenthic, 130-260 m.
Remarks
This species can be distinguished by the short tongue-like rostrum; the naked outer margin of the antennal scale; the relative lengths of the terminal spine and the apex of the scale; the very large closely set eyes; the length of the endopod of the last thoracic limb which only extends to the anterior margin of the last thoracic somite; the convex posterior margin of the telson; the short outer spines (half as long as the inner) on the telson in both sexes and the absence of serrulations on the inner margin of the endopod of the uropod. In living specimens the whitish marks on the body and the particularly brilliant pigment spots are the best guide but these disappear in preserved specimens.
Distribution in the North Sea
Northern North Sea.
World distribution
North Atlantic: 50-79°N; Coastal to shelf.
[After Tattersall and Tattersall, 1951]