The Isopods of Abyssal Depths in the Atlantic Ocean

differing in the sculpture on the dorsum of the
pleon.
Serolis (Serolis) vemae, new species
Figure 67
Synonyms: None.
Diagnosis: Serolis with coxal plates marked off on
peraeonal somites 2-5 inclusive. Third article of
maxillipedal palp small. Uropoda biramous, exopod
minute, endopod thick projecting beyond posterior
margin of pleon. Pleon without postero-lateral angles,
apex pointed, mid-dorsal carina entire, lateral or
transverse carinae lacking. Lateral borders of peraeon
not pointed and produced but quadrate. Peraeonal
somites 5 and 6 with a small mid-dorsal spine. Flagellum
of second antenna shorter than last peduncular
article. Flagellum of first antenna with ten articles.
Measurements: Hoiatype male 4.3 mm., width
1.7 mm.
Type locality: South Atlantic, L.G.O. Biotrawl No.
12, type only, cat. no. 1-89.
Distribution: Also from L.G.O. Biotrawl No. 51,
one female, cat. no. 1-196.
Affinities: This species is unique, not falling into any
of the subgroups mentioned by Nordenstam (1933).
Serolis (Serolis) maryannae, new species
Figure 68
Synonyms: None.
Figure 68. Serolis (Serolis) maryannae, n. sp..
dorsal view female holotype.
ABYSSAL ATLANTIC ISOPODS 189
Diagnosis: Serolis with coxal plates marked off on
peraeonal somites 2-5. Third article of maxillipedal
palp small. Uropoda biramous. Pleon with sharp
pointed median posterior extension of mid-dorsal
carina; lateral carinae lacking. First peraeonal
somite with pronounced spine at antero-lateral angle.
Eye lobes present, cephalon with mid-dorsal tubercle
at posterior end. Each peraeonite except first somite
with tubercle at posterior border at midline. Pleon
lacking postero-lateral angles. Epimera of sixth
peraeonal somite extending beyond apex of pleon by
one times its length. Uropodal rami blunt, exopod
one-third shorter than endopod, not extending to
posterior margin of pleon.
Measurements: Female holotype length 18.8 mm,
width pleon 7.2 mm.
Type locality: South Atlantic, L.G.O. Biotrawl No.
201, type only, cat. no. 1-225.
Distribution: Known only from type locality.
Affinities: The serrated pleonal apex of this species
is unique. Otherwise the species is very close to S.
(S.) macdonnellae.
GLABROSEROLIS, new genus
Type species: Glabroserolis specialis, n. sp.
Diagnosis: Serolidae with uniramous uropoda.
Coxal plates not marked off on any peraeonal somite.
First antenna one-half the width of expanded peduncular
article of second. Second article of maxillipedal
palp quadrate, not cordate. Basipodites of pleopods
1-3 with projecting setiferous inner proximal angles.
Composition: Unique.
Glabroserolis specialis, new species
Figure 69
Synonyms: None.
Diagnosis: Glabroserolis with shield-shaped pleon
devoid of carinae or postero-lateral angles. Endopod
of uropod pointed, one-third longer than peduncle,
not visible in dorsal view. Lateral borders of peraeon
quadrate, not projecting. Flagellum of second antenna
shorter than last peduncular article.
Measurements: Holotype female length 3.3 mm.,
width pleon 1.95 mm.
Type locality: South Atlantic, L.G.O. Biotrawl No.
53, type and one female, one fragment, cat. no.
1-194.
Distribution: Known only from type locality.
Affinities: A unique species in a unique genus. To
a certain extent the genus resembles Spinoserolis
Nordenstam, but it lacks coxal plate demarcation
entirely and has the unusually expanded peduncular
articles of the second antenna.