Amblyops kempi

(Holt and Tattersall, 1905)

Description
Generic features. Statocyst usually present. Pleopods of female reduced, rudimentary; of male variable. Endopod (and exopod) of uropod without spines. Outer margin of antennal scale without setae; ending in terminal tooth. Eyeplates quadrangular, outer corners rounded, margins not serrulated. Eyes often rudimentary in the form of flat plates without definite stalks. Telson rounded. Lateral margins of telson and apex armed with a graduated series of spines and a pair of median setae. Marsupium consists, as in the Genus Pseudomma, of two well-developed incubatory brood lamellae.
—ÊSpecies. Body somewhat robust. Carapace slightly wider than the abdomen, anterior margin rounded to a bluntly rounded, very obtuse angle, cervical sulcus well marked, posterior margin emarginate.
Eyes in the form of completely separated, broadly oblong, ocular plates; surface armed sparsely with minute spinules which are more dense and pronounced in the antero-lateral region; in larger specimens the plate is drawn out into a distinct lobe near the antero-distal angle.
Antennal peduncle relatively short, equal in length to the antennular peduncle. First segment imperfectly divided, second segment overhanging the first dorsally making the peduncle appear distorted, especially in lateral view.
Antennular scale about twice as long as the peduncle, tapering slightly towards the apex, with the widest part about one-third of the length of the scale from its proximal end; outer margin slightly convex, terminating in a prominent spine which extends beyond the apex of the scale and which may be armed with a small secondary spine on its inner margin; very large spine on the outer distal angle of the sympod.
Uropod long and slender. Exopod more than one and a half times as long as the telson. Endopod shorter and more slender, usually armed with a single, long slender spine on the inner margin in the region of the statocyst.
Telson equal in length to the last abdominal somite, narrowed abruptly close to the base, tapering very slightly to the broadly rounded, entire apex; apex armed with a median pair of minute spinules and two pairs of long slender spines which form the culmination of an evenly graduated series of 27-28 spines arming each lateral margin; a pair of plumose setae present above the median spinules.

Colour
Similar to Amblyops abbreviata: anterior portion of body transparent and colourless except for the eyeplates which are covered with very minute red specks of pigment and appear rosy red in colour. The large gut shows through the integument as a reddish mass and the yellow liver is also cleurly visible. The abdomen is sparsely covered with minute, evenly distributed, red specks.

Size
Length of both sexes up to 16 mm.

Depth range
Hyperbenthic, bathypelagic. The species occurs just clear of the bottom in depths of 700-1500 m. It is most abundant between 1100-1500 m.

Remarks
Amblyops kempi can be distinguished from Amblyops abbreviata by:

- the presence of spinules all over the eyeplates,
- the particularly large spine on the basal joint of the antenna,
- the long slender spines on the endopod of the uropod and,
- the shape and armature of the telson.

Amblyops kempi is evidently a deeper water form than Amblyops abbreviata, but there is still overlap in the distributions of the two species. Amblyops kempi lives close to the sea bottom making only short occasional excursions into the lower levels of water just above the floor.

Distribution in the North Sea
Probably rarae in the northern North Sea.

World distribution
North Atlantic, 44 - 64°N; shelf. Coastal to bathyal; e.g. west coast of Ireland, west of the Hebrides, Faeroes.

[After Tattersall and Tattersall, 1951]

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