The Isopods of Abyssal Depths in the Atlantic Ocean

ABYSSAL ATLANTIC ISOPODS 185
Figure 64. A-G: Mesosignum kohleri, n. sp. A: mandible; B: uropod; C: first pleopod;
D: dorsal view male holotype; E: maxilliped; F: first peraeopod; G: third pleopod.
H-J: Mesosignum usheri, n. sp. H: dorsal view male holotype; I: first pleopod; J: uropod.
Affinities: Near to usheri but without stout spine at
postero-lateral angle of pleon.
Mesosignum usheri, new species
Figure 64 H-J
Synonyms: None.
Diagnosis: Mesosignum with stout spinulate posterolateral
spines at apex of pleon. Frons of cephalon
evenly rounded. Antero-lateral spine of second
peraeonal somite five times the length of posterolateral
spine and extending forward beyond peduncle
of first antenna. Apex of male first pleopod straight,
with eight marginal setae.
Measurements: Holotype male length 2.0 mm.,
width pleotelson 0.3 mm., allotype length 2.1 mm.,
width pleotelson 0.4 mm.
Type locality: North Atlantic, Caribbean, L.G.O.
Biotrawl No. 98, types plus one female, cat. no.
1-87-88.
Distribution: Known only from type locality.
Affinities: Near to kohleri but with stout spine at
postero-lateral angles of pleon.