Remarkable Australasian marine diversity: 18 new species in Pentaceration Just, 2009 (Crustacea, Isopoda, Paramunnidae)
Author
Just, Jean
text
Zootaxa
2011
2813
1
54
journal article
10.5281/zenodo.203856
60e82aa4-3a36-4f25-82a2-23acef2974c2
1175-5326
203856
Pentaceration epipedos
sp. nov.
Figure 31
Type
fixation.
Holotype
, male, here designated.
Etymology.
The epithet is the Greek adjective επίπεδος (
epipedos
) meaning flat, alluding to the unusually flattened body of the species.
FIGURE 31.
Pentaceration epipedos
sp. nov.
Holotype, 3, except
M
, paratype, 3.
a
, antenna;
au
,
antennula
;
cv
, head ventral view;
p1
, pereopod 1;
pl1–2
, pleopods 1 and 2;
up
, uropod. Habitus scale: 0.5 mm.
Material examined.
Holotype
,
3,
1.72 mm
,
New Zealand
, Campbell Plateau, Pukaki Rise,
49°25'S
,
172°07'E
,
330–338 m
,
7 September 2000
, RV
Tangaroa
, stn TN0009/4,
NIWA
29714.
Paratype
. Same data as
holotype
,
NIWA
60504 (1 3,
1.65 mm
).
Description
.
Body
strongly dorsoventrally flattened, barely tapering from pereonite 2 towards pleon; width 0.47 length, widest between pereonites 6 and 7.
Head
length 0.22 width; length posterior to eyestalks 1.8 anterior length.
Frontal margin
middle spine length 0.85 head length; lateral spines 1.4 middle spine length, diverging at 110°; all 3 spines smooth with few short setae.
Eyestalks
over reaching lateral margin of pereonite 1 with approximately 10% of their length, pointing forward at 10º, slightly narrower near base, apex pointed.
Pereonite
1 lateral margins rounded, with short pointed mid spine; pereonites 2 and 3 with straight, pointed lateral spines of 0.45 pereonite width, 2 pointing forward at approximately 20º, 3 pointing directly laterad; pereonites 2–3 spines diverging at 20
°
; pereonite 4 with short, slender, pointed lateral spines; pereonite 5 lateral spines similar to pereonite 3 spines but slightly broader; pereonites 6 and 7 lateral spine broadly triangular, 6 slightly larger than 7, both with narrow translucent flange along anterior margins; pereonites 5 and 6 with long row of simple setae posterolaterally where overlapping succeeding pereonite.
Pleon
of equal length and width.
Pleonite
1 width 1.25 distance between uropods, length approximately 0.1 width.
Pleotelson
proximal and lateral margins evenly merging, lateral margins evenly rounded, with approximately12–14 denticles (both sides somewhat damaged); distal projection triangular at 80°, 0.3 length of entire pleotelson, apex bluntly pointed.
Antennula
articles 1 and 2 combined reaching to apex of eyestalks; article 1 1.4 length of 2, tubular; 3 and 4 of subequal length, both 0.6 length of 5 which is 0.85 length of 6.
Antenna
article
2 in
ventral view approximately 6 times length of 1; 3 width 0.35 length.
Pereopod I
basis length 2.9 width; ischium 0.65 length of basis; merus with 2 acute spines on anterior margin; carpus oval, distal margin straight; propodus narrowing distally to insertion of dactylus, with 2 robust setae on opposing margin.
Pleopod I
lateral sublobes dissimilar, proximal one bluntly triangular, partly overlapping distal one which carry row of simple setae; width 0.28 distance to midline; distal projection length 0.3 pleopod total length, forming acute angle, with bluntly pointed apices.
Pleopod II
protopod rounded distally; endopod article 2 (stylet) forming 80° curve.
Uropods
recessed into simple cuticle hood, protopod and exopod apparently absent; endopod length 3.6 width.
Size.
Largest male,
1.72 mm
.
Distribution.
New Zealand
, Campbell Plateau,
330–
338 m
.