The Marine Fauna of New Zealand: Isopoda, Aegidae (Crustacea)

distribution: Known only from the Poor Knights Islands,
northern New Zealand.
etymoLogy: The epithet insomnis (from the L. meaning
sleepless; noun in apposition) is a play on the name of
the type locality.
Aegiochus kakai sp. nov. (Figs 6 –64)
materiaL examined: Holotype. ♂ ( 4.2 mm), Chatham
Rise, 42°43.20’S, 79°57.63’W, 2 April 200 , 0 2–890
m, coll. RV Tangaroa (NIWA 23863).
Paratypes. All Chatham Rise. 4 ♂ ( 2.5 [damaged],
3.6, 4.5 dissected, 6.0 mm), 5 ♀ (ovig. 5.0, 5.5; nonovig.
2.5, 5.5, 24.5), same data as holotype (NIWA
23864). 6 ♂ ( .0. .2, 2.2, 2.8, 3.5, 4.5 mm), 4 ♀
(ovig. 3.8, 5.0, 6.5; non-ovig. 6.5 mm), 5 April 200 ,
42°42.84’S, 79°57.5 ’W, 980–893 m, coll. RV Tangaroa
(NIWA 23865). ♀ (non-ovig. 8.5 mm), Chatham Rise,
5 April 200 , 42°45.93’S, 79°59.34’W, 875–757 m, coll.
RV Tangaroa (NIWA 23866); 2 ♀ (ovig. 4.5, 5.0 mm),
6 April 200 , 42°47. 7’S, 79°59. 2’W, 993–900 m, coll.
RV Tangaroa (NIWA 23867).
Non-type material, some not measured. ♀ (non-ovig.),
7 April 200 , 42°48.24’S, 79°59.27’E, 0 3–93 m
(NIWA 23868). 2 ♀ (ovig.), 2 April 200 , 42°42.76’S,
79°54.45’W, 080– 008 m (NIWA 23869). ♀ (ovig.), 8
April 200 , 42°47.27’S, 79°59.8 ’W, 042–880 m (NIWA
23870). ♀ (ovig. 5.7 mm) 6 July 994, 43°5 .47’S,
74° 7.08’W, 754 m (NIWA 23870). 2, 42.7275–7307°S,
80. 0 0–0973°E, 7 June 2006, 000– 07 m, (NIWA
25670, 2567 ). , 42.7 58–7 32°S, 80. 432–0480°E,
4 June 2006, 950– 070 m (NIWA 25668). , 42.7627–
7575°S, 80.0748–0773°E, 28 May 2006, 0 9– 08 m
(NIWA 25656).
desCription: Body 2. times as long as greatest width,
dorsal surfaces polished in appearance, widest at pereonite
5, lateral margins weakly ovate. Rostral point
folded ventrally and posteriorly. Eyes large, medially
united, anterior clear field 27% length of head, posterior
clear field 44% length of head; each eye made up
of ~ 6 transverse rows of ommatidia, each row with
~9 ommatidia; eye colour red, or dark brown. Pereonite
1 and coxae 2–3 each with posteroventral angle with
small distinct produced point. Coxae 5–7 with entire
oblique carina; posterior margins concave, posterolateral
angle acute (less than 45°). Pleon with pleonite
visible in dorsal view; pleonite 4 with posterolateral
margins extending clearly beyond posterior margin of
pleonite 5; pleonite 5 with posterolateral angles overlapped
by lateral margins of pleonite 4. Pleotelson 0.7
times as long as anterior width, dorsal surface without
longitudinal carina; lateral margins convex, serrate or
notched, posterior margin converging to caudomedial
point, with 8– 0 RS.
Antennule peduncle articles 3 and 4 . times as
long as combined lengths of articles and 2, article 3
4.1 times as long as wide; flagellum with 10 articles,
extending to posterior of pereonite . Antenna peduncle
article 4 2.9 times as long as wide, 0.9 times as long as
combined lengths of articles –3, inferior margin with
plumose seta, and 4 short simple setae (anterodistal
3 simple + plumose); article 5 .0 times as long as article
4, 2.7 times as long as wide, inferior margin with 3
palmate setae, anterodistal angle with cluster of 3 short
simple setae; flagellum with 15 articles, extending to
posterior of pereonite 3.
Frontal lamina posterior margin free, downwardly
projecting, blade-like, wider than long, posterior
margin concave, anterior margin anteriorly truncate
(narrowly), forming median angle, posterior margin
not abutting clypeus.
Mandible molar process present, small distinct flat
lobe; palp article 2 with distolateral setae (4 large
and 5 small biserrate, 2 simple distally), palp article 3
with 20 setae (all biserrate). Maxillule with 5 terminal
RS ( large, 4 slender). Maxilla mesial lobe with 3 RS (
straight, 2 biserrate); lateral lobe with 2 RS (hooked).
Maxilliped endite with 0 apical setae; palp article 2
with 2 RS; article 3 with 4 recurved RS (2 slender, 2
hooked); article 4 with 4 hooked RS; article 5 with 4
RS (straight).
Pereopod 1 basis 2.7 times as long as greatest width;
ischium 0.4 times as long as basis, inferior margin with
0 RS, superior distal margin with RS; merus inferior
margin with 2 RS (minute), set as two groups, superior
distal angle with 0 RS (2 short slender setae); carpus 0.7
as long as merus, inferior margin with RS; propodus
2.3 times as long as proximal width, inferior margin
with 0 RS, propodal palm simple, without blade or
process, dactylus smoothly curved, .4 as long as propodus.
Pereopod 2 ischium inferior margin with 0 RS,
superior distal margin with RS; merus inferior margin
with 4 RS (distalmost large, remainder minute), set as
two groups, superior distal margin with acute RS
(small plus 2 slender setae); carpus longer than that of
pereopod , with inferodistal lobe, inferodistal angle
with RS. Pereopod 3 similar to pereopod 2. Pereopods
5–7 inferior margins of ischium–carpus with short
RS. Pereopod 6 similar to pereopod 7 (but longer, with
slightly more RS). Pereopod 7 basis 3.6 times as long
as greatest width, inferior margins with palmate
setae; ischium 0.4 as long as basis, inferior margin
with 3 RS (set as , and ), superior distal angle with
2 RS, inferior distal angle with 4 RS; merus .2 as long
as ischium, 2.5 times as long as wide, inferior margin
with 3 RS (set as and 2), superior distal angle with 7
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