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Some Amphipoda, Isopoda and Tanaidacea from Cook Strait
Order Isopoda
Order Isopoda
S.O. Flabellifera
Family Eurydicidae
Cirolana quadripustulata n.sp. (Figs. 25–38).
Diagnosis: Very large, 40–60 mm. Frontal lamina long, thin; maxilla 1 has 4 spines on inner plate; antenna 1 almost reaches 1st thoracic segment; antenna 2 reaches 5th. Eyes long, subrectangular. Peraeopod 7, 2nd segment broad, setose; abdominal segment 3 strongly produced laterally to cover 4th and 5th and reaching base of uropod. Male, thoracic segments 3 and 4 have each 2 small tubercles dorsally, those on 3rd segment prominent, those on 4th less distinct. Penial processes are indistinct tubercles; appendix masculina long, slender, barely curved at tip.
Body: Head width more than twice length, anterior margin somewhat concave. Eyes of 10–11 rows of ocelli from 2nd antenna peduncle back to posterior margin of head, cover most of side of head which is separated from dorsal surface by slight ridge. Body segments of more or less equal width, 1st and 4th longest; coxal plates distinct, ventrally setose, last 4 with slightly produced acute posterodistal angles, 7th reaches back to partly cover lateral surface of 2nd abdominal segment. 3rd and 4th abdominal segments laterally produced back to base of uropod. Telson distally rounded, setose, has 7 spines along distal margin.
Antennae. First: Short, as long as eye and lying along it; flagellum of 38–40 short wide segments, each has row of long flaccid sensory setae, forming tract along entire flagellum. Peduncle 1st segment not quite twice length 2nd; 2nd about ¾ 3rd; each has 1–2 plumose setae on margins, an especially long one on inner distal angle of 3rd; 3rd has bristled flange lengthwise down surface. Second: Flagellum longer than peduncle, of more than 50 segments. Peduncle, 2nd segment about ½ length 3rd, 3rd and 4th subequal, ½ length 5th.
Mouthparts. Maxilliped has 2 coupling spines.
Peraeopods. First: 4th and 5th segments posteriorly subequal but overlapping each other; 4th has about 4 spines distally on posterior margin, 3 on protuberance ½ along; posterodistally produced in setose-margined thumb about 1/3 along 6th segment, stout end spine on thumb. 5th has spine, seta, along posterior margin. Segment 6 has posterior margin as long as 5th, anterior twice as long, has 5 spines and setae. Dactylos long, tapering. Second: Generally similar, 3rd segment has 3 strong spines on posterodistal angle; 4th has 3 strong spines on anterodistal thumb which reaches ½ along segment 6; 5th has spine medially, 2 distally on posterior margin, is more distinct from segment 4 than in Gn. 1. Segment 6 slightly longer than 5, has 4–5 short spines on posterior margin. Dactylos has group of small spines near small end boss. Seventh: 2nd segment broad, especially distally where width ½ length; strongly setose on rounded anterodistal angle, all along posterior margin, also right along median surface flange. 3rd segment 2/3 2nd, triangular, anteriorly spinose and setae, posteriorly setose, distally spinose. 4th and 5th subequal, slightly shorter than 3rd; 4th-6th segments have 3–4 groups of spines and setae on anterior margin, spines and setae on posterodistal angle, rest of posterior margin naked; 6th slightly shorter than 5th.
Pleopods. Male stylet on 2nd reaches about 2/3 down endopod.
Uropods. Long acute peduncle process reaches ½ down endopod, has setose outer margin. Exopod slender, width about ¼ length, about 11 spines down outer margin, 3 on inner, 1 on distally narrowed tip, margins setose; exopod reaches about 2/3 down wide subrectangular endopod which has 6 spines on outer margin, outer distal angle distinct, inner rounded, distal margin has 8 spines, all margins setose. Distal width about 1/3 length.
Material Examined: Station COS (VUZ. 22), 2 males, 52–58 mm; Station BOP (VUZ. 41), 9 females, 42–48 mm; "Thomas Carrol", 4/4/53, Palliser Bay, 40 fathoms, 1 male, 60 mm.
Types: Slides Oc. 7 (VUZ. 22, male).
Distribution: Cook Strait, N.Z.
Discussion: Despite the large size of this species and the great number of species of Cirolana already known, I cannot identify these specimens with any previously described species. The prominent tubercles on the back of the male, and the strong backward prolongation of the 3rd abdominal segment are especially characteristic.
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Rocinela garricki n.sp. Male.
Fig. 39.—Adult male. Fig. 40.—Ventral surface of head showing frontal lamina. Fig. 41.—Antenna 1. Fig. 42.—Antenna 2. Fig. 43.—Mandible and detail from palp surface. Fig. 44.—Maxilliped. Fig. 45.—Peraeopod. Fig. 46.—Peraeopod 7. Fig. 48.—Pleotelson and uropod. Fig. 49.—Portion of Pleotelson end margin and surface.
The males from Station COS are noteworthy for the presence of developing gasteropod eggs on the ventral surface of the body between the legs. This is to my knowledge the first record of this unusual association. There is no evidence to indicate whether this develops into a commensal or parasitic relationship when the gasteropod is fully grown or not.
Cirolana pellucida Tattersall, 1921.
Cirolana Pellucida Tattersall, 1921: 206–207, pl. II, figs. 4–10.
Material Examined: Station KIIB (VUZ. 3), 'Regina, Stephens Island, 541217A', 4 females, 6–17 mm; Station GIIB (VUZ. 6), 1 female, 17 mm; Station CUF (VUZ. 19), 1 male, 8 mm, 1 female, 7 mm.
Distribution: Cook Strait; Terra Nova Stations 86, 129, 130 "off Three Kings Islands, plankton, from the surface and 3 metres"; Terra Nova Station 133, Spirits Bay, near N. Cape, N.Z., plankton, at 20 metres.
Discussion: Tattersall has remarked on the thin pellicle of this species, evident here in specimens from Station KIIB and CUF. Those from Station KIIB have a harder exoskeleton. The eyes show some variation; the KIIB specimens have a large subrectangular eye along most of the head; the GIIB specimen has one eye like this, the other superficially smaller and rounder like the CUF specimens. This is almost certainly due to leaching out of pigment. The CUF male has a somewhat blunter penis than that figured by Tattersall for his specimens; the GIIB specimen has small brownish-red pigment spots still visible over the body.
Family Aegidae
Rocinela garricki n.sp. (Figs. 39–49).
Diagnosis: Frontal margin of head triangular, subacute; frontal lamina longer than wide. Peraeopod 1, 3rd segment lacks spines; 5th has 3 strong spines, 6th has 9 closely-set spinet on posterior margin. Last 4 peraeopods notably different from 1st 3.
Body: Cephalon wider than long, overhanging bases of antennae. Eyes large, oval, well-separated, ocelli separated. Thorax, 1st 3 segments subequal in length, 4th longer, 6th and especially 7th much shorter, the last almost completely hiding 1st abdominal segment. Remaining 4 abdominal segments subequal, lateral margins of 4th covering those of 5th. Coxal plates distinct in dorsal view, the last reaching well back past 1st abdominal segment. Telson distally rounded, finely scaled and minutely setose, margin strongly fringed with plumose setae, about 9 spines around distal margin.
Antennae. First: Does not quite reach end of peduncle of 2nd; flagellum of 6 small segments, the last 5 with 2 flaccid sensory setae distally on each; peduncle of 3 segments, 3rd the largest Second: Reaches end of 2nd thoracic segment, peduncle 1st segment longer than 2nd, almost as long as 3rd, 4th barely shorter and about ¾ length 5th; flagellum of about 11 segments.
Mouthparts. Mandible: Small tubercular molar process; palp of 3 segments, 1st naked, barely shorter than 2nd which has about 9 plumose setae marginally, 6 setae on surface; 3rd about ½ length 2nd, about 9 setae on concave margin, 2 small end spines. Surface, of 2nd segment especially, comb-scaled. Maxilliped: Palp 2nd segment has 3 end spines, one on surface.
Peraeopods. First: Second segment, length more than twice width, a few marginal setae; 3rd narrower, ½ as long, 3 long setae anterodistally; 4th about 2/3 as long, subtriangular, 5–6 setae anterodistally, 1 spine proximally on posterior margin, 2 distally; 5th very short, partially concealed; 6th as long as 4th, as wide as long, a few setae anterodistally; posterior margin produced in blade-like expansion with 9 strong spines, a few fine setae behind spines; 7th long, curved, slender, more than twice length 6th. Second: 6th segment has 8 spines. Third: 6th segment has 7 spines. Seventh: Long, relatively slender; 2nd segment especially long, has a few marginal setae; 3rd a little shorter, narrower, widens a little distally, 3 spines anteriorly, strong spine-groups on distal angles; 4th about 2/5 length 3rd, pair of spines ½ along anterior surface, groups on distal angles, 5th a little longer, similar; 6th a little shorter than 5th, 4 spines anteriorly; dactylos short and curved.
Second Pleopod. Blunt slender male stylet reaches ½ down endopod; rami subequal, fringed with setae, exopod has longitudinal row of clear circular patches which are probably glandular down surface, is distally notched.
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Astacilla levis Thomson & Anderton. Male.
Fig. 50.—Adult male. Fig. 51.—Head and 1st thoracic segment, side view. Fig. 52.—Head and 1st thoracic segment, dorsal view. Fig. 53.—Pleotelson, dorsal view. Fig. 54.—Antenna 1. Fig. 55.—Maxilliped. Fig. 56.—Peraeopod 1. Fig. 57.—Peraeopod 2. Fig. 58.—Peraeopod 2, dactylos. Fig. 59.—Peraeopod 5. Fig. 60.—Peraeopod 5, dactylos. Fig. 61.—Uropod.
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Astacilla levis Thomson & Anderton. Male.
Fig. 62.—Antenna 2. Fig. 63.—Antenna 2, detail of scales and setae. Fig. 64.—Antenna 2, flagellum. Fig. 65.—Antenna 2, flagellum, detail of margin. Fig. 66.—Pleopod 2 and male stylet.
Jaeropsis palliseri n.sp. Male.
Fig. 67.—Antenna 1. Fig. 68.—Antenna 2. Fig. 69.—Maxilliped. Fig. 70.—Maxilliped, endite detail. Fig. 71.—Maxilla 2. Fig. 72.—Pleopod 1. Fig. 73.—Uropod.
Uropod. Rami ovate, endopod slightly the longer, the more rounded distally; margins strongly setose; 7 spines on outer margin of exopod, about 3 distally on outer margin of endopod. Peduncle inner process reaches ½ down endopod.
Material Examined: Station BOL (VUZ. 43), 1 male, 155 mm.
Types : Slides Oc. 5.
Distribution: Cook Strait.
Discussion: In general, this species is very close to R. orientalis (cf. Hale, 1925; Stebbing, 1905). It is distinguished from this and all other species of the genus by the 9 spines on segment 6 of peraeopod 1. R. latis (Southwell, 1915) has 8 spines but is stated to have "the four gressorial legs ... very similar to the 1st 3 pairs of legs but a little more slender". The species is named for Mr. J. A. Garrick who has been responsible for much of the collecting.
Family Sphaeromidae
Sub-family Sphaerominae-Sphaerominae Platybranchiatae
Cassidina typa M. Edwards, 1840.
Cassidina typa M. Edwards, 1840: 224, pl. 32, figs. 10–16.
Tattersall, 1921: 226–227.
Cassidina neo-zealanica G. M. Thomson, 1889: 264, pl. 14, figs. 1–4.
Material Examined: Station BOL (VUZ. 43), 8 specimens; Station BOK (VUZ. 44), 2 males, 10mm, 6 females, 6–9 mm; Station BOL (VUZ. 48), 1 male, 12 mm; Station BOL (VUZ. 49), 1 female, 8 mm, ovigerous; 2 males, 10–11 mm.
Distribution: Cook Strait, Bay of Islands, Akaroa Harbour, Spirits Bay, Otago Harbour, Blueskin Bay.
Discussion: This flattened plate-like species is common on sandy bottoms around New Zealand from 0–100 fathoms. Thomson refers to it being found frequently on seaweed. It is common amongst the debris taken in flatfish trawls off Otago Harbour.
Family Serolidae
Serolis bromleyana, Suhm, 1874.
Serolis bromleyana Suhm, 1874: xix.
Beddard, 1884: pp. 53–57, pl. iv.
Sheppard, 1933: 329–330, 280.
Material Examined: Station BOP (VUZ. 41), 2 males, 22–23 mm, 3 females, 22–26 mm; Station DOP (VUZ. 51), 1 male, 15 mm (incomplete), 3 females, 11–23 mm, one at 23 mm ovigerous; Station HUL (VUZ. 53), 6 females, 12–20 mm; Station GUL (VUZ. 54), 48 males, 15–28 mm, 15 ovigerous females, 23–28 mm, 17 juveniles, 7–15 mm; Station FOOR (VUZ. 58), 1 female, ovigerous, 34 mm.
Distribution: Cook Strait; "off the east coast of New Zealand, in 1,100 and 700 fathoms, and close to the Antarctic Ice-Barrier in 1,975 fathoms".
Discussion: These trilobite-looking animals are apparently common and perhaps even a dominant part of the bottom fauna in the deeper waters around New Zealand.
Sub-Order Valvifera
Family Arcturidae
Astacilla levis Thomson & Anderton, 1921. (Figs. 50–66).
Astacilla sp. Thomson & Anderton, 1921: 114–115, text-fig.
Body. Smooth and whitish: head anteriorly rounded, fused with 1st thoracic segment, segmentation indicated only by distinct groove with short incision at base of groove ventrally. Eyes black, large, subtriangular. Head and 1st 3 segments about ¾ length 4th thoracic segment, 2nd and 3rd segments subequal and each slightly shorter than 1st; 4th barely shorter than remaining thoracic and abdominal segments combined. Abdominal segments smooth, fused, segmentation indicated only by slight ventral incisions, shallow grooves, 1st especially faint. Pleotelson fused, defined only by shallow groove.
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Pseudidothea richardsoni n.sp. Female.
Fig. 74.—Adult female, dorsal view. Fig. 75.—Adult female, side view. Fig. 76.—Antenna 1. Fig. 77.—Antenna 2. Fig. 78.—Antenna 2, flagellum. Fig. 79.—Maxilliped. Fig. 80.—Mandible. Fig. 81.—Maxilla 1. Fig. 82.—Peraeopod 1. Fig. 83.—Pleopod 1. Fig. 84.—Pleopod 2. Fig. 85.—Pleopod 3. Fig. 86.—Uropod.
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Pseudidothea richardsoni n.sp. Female.
Fig. 87.—Peraeopod 2. Fig. 88.—Peraeopod 7. Figs.. 89–90.—Peraeopod 7, left and right dactyli. Fig. 91.—Uropod.
Iathrippa longicauda (Chilton). Female.
Fig. 92.—Antenna 1. Fig. 93.—Maxilliped. Fig. 94.—Maxilliped, detail of endite. Fig. 95.—Maxilla 2. Fig. 96.—Pleopod 3. Fig. 97.—Uropod.
Antennae. First: Basal segment a little expanded, ovate. Second: Peduncle 2nd segment ¾ length 3rd; 3rd not ½ length 4th; 5th ¾ 4th; 3-segmented flagellum not 2/3 length 5th, has stout end nail; flagellar segments have double row of strong spine-teeth right along inferior surface. Peduncle segments have fine scattered setae on surface, scaled around bases of setae. Antennae as long as head and 1st 4 thoracic segments.
Mouth parts. Maxilliped: Has 2 coupling spines.
Peraeopods. First: Normal, claw absent. Second-Fourth: End segment has short but distinct terminal claw. Fifth: Dactylos has 2 end spines; inner margin has 4–5 small corrugations proximally.
Pleopods. Male stylet on 2nd longer than pleopod rami, its proximal 3/5 relatively stout, distal 2/5 tapering to long slender seta-like process.
Uropods. Secondary ramus 1/3 to ½ length primary, much smaller, has 3 long plumose end setae, a smaller marginal seta.
Material Examined: Station BOL (VUZ. 43), 1 male, 12.5 mm; Station BOL (VUZ. 49), 1 male, 11mm (Slide Oc. 2), 1 female, 12 mm, ovigerous.
Distribution: Cook Strait; "trawl in 17 fathoms, about 3 miles east-southeast of Otago Heads, on the 30th December, 1919" (G. M. Thomson).
Discussion: Thomson and Anderton have briefly described and figured a species for which they suggest the name Astacilla levis might be used. I believe these specimens belong to their species, although they do not give a great deal of information. The species is easily distinguished from most other smooth-bodied Astacilla species, e.g. falclandica, kerguelensis, macilenta, algensis, deducta, vicaria and magellanica, with which it might otherwise be identified, by the three apical setae on the secondary ramus of the uropod.
Other New Zealand species are falclandica (Tattersall, 1921: 244), fusiformis (Hale, 1946: 185), and tuberculata (Thomson, 1879a: 416).
Family Pseudidotheidae
"Besides the usual male appendix on the endopodite of the second pair of pleopods, also the first pair of pleopods is in the male transformed into a copulatory organ. Body elongate. Segments of pleon all coalesced. Antennulae small. Flagellum consisting of one joint. Antennae strong, half as long as body. Peduncle 4-jointed, 1st and 2nd joint being coalesced, with the suture visible only from below, flagellum 2-jointed. Palpus of maxillipeds 5-jointed. Second-seventh pairs of pereiopods of nearly the same size and structure, with prehensile dactyl us. First pair much the shorter, its propodus and dactylus strong and armed with stout, in part serrated spines. Uropods with two small lamellae."
—Ohlin.
Genus Pseudidothea Ohlin, 1901.
"Head fused with the first segment of the pereion, being separated from the latter only by a faint groove. Eyes small, situated laterally. Coxae developed as incomplete, not very distinct, rings around the proximal ends of the basipodites of the second to seventh pereiopods. All segments of abdomen fused into one piece. Antennae with a two-jointed flagellum. Maxillipeds with a five-jointed palp. First pair of pereiopods prehensile. Penis cleft distally. Second male pleopod with the exopodite transformed and traversed by a diagonal channel. Uropods with two branches, the 'secondary' branch being about three-fourths the length of the lateral one and provided with a single large seta at the tip."
—Nordenstam.
Pseudidothea richardsoni n.sp. (Figs. 74–91).
Diagnosis: Antenna 2, last 3 segments of peduncle have inferior margin well supplied with long strong spine-setae; peraeopods, 2nd segments lack marginal tubercles; uropod, primary ramus has 3 plumose setae distally.
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Iathrippa longicauda (Chilton). Female.
Fig. 98.—Adult female. Fig. 99.—Antenna 1. Fig. 100.—Maxilla 1. Fig. 101.—Mandible. Fig. 102.—Peraeopod I. Fig. 103.—Peraeopod 1, dactylos. Fig. 104.—Peraeopod 7. Fig. 105.—Peraeopod 7, dactylos. Fig. 106.—Pleopod 2. Fig. 107.—Operculum.
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Jaeropsis palliseri n.sp. Male.
Fig. 108.—Adult male. Fig. 109.—Maxilla 1. Fig. 110.—Mandible. Fig. 111.—Peraeopod 1. Fig. 112.—Peraeopod 1, dactylos. Fig. 113.—Peraeopod 7. Fig. 114.—Peraeopod 7, dactylos. Fig. 115.—Pleopod 2. Fig. 116.—Pleopod 2, detail. Fig. 117.—Pleopod 3.
fur of sediment; body segments mildly tuberculate, the tubercles really little more than suggested (and a little exaggerated in the figures). Limbs, pleon, and uropods quite setose and furred.Antennae. First: First segment subrectangular, almost as wide as long, almost as long as 2nd and 3rd combined; slightly longer than 4th which has end tuft of about 6 flaccid sensory setae. Finely furred margins, a few plumose setae, especially on 2nd segment. Second: Peduncle, 2nd segment 2/3 length 3rd, 3rd slightly shorter than subequal 4th and 5th, the last 2 having a few fine surface setae, the last 3 having strong spines on inferior margins. Flagellum short, 1st segment with long end seta inferiorly, 2nd with terminal "nail" spine as long as itself. Furred.
Mouthparts. Maxilliped: Endite furred, quite wide, almost ovate, rounded end margin has about 4 plumose setae; no sign of coupling hooks. Palp 1st 2 segments short, 3rd ovate, as long as 4th and 5th combined, has about 5 short plumose setae on inner margin; 4th slender, has 4–5 plumose setae on inner margin, one on outer distal angle; 5th a short dome ½ length 4th, has about 4 terminal plumose setae. Mandible: Left has lacinia, 3 spines in spine row; molar process short, distally wide with jagged end margin, 4 setae in middle of end margin. Maxilla 1: Outer plate has 11 plumose setae; inner plate narrow, slightly shorter, has 3 plumose end setae.
Peraeopods. First: Short, strong, ischium about ½ basos length, carpus as long as ischium, merus shorter; all 4 segments finely furred; ischium has 1 spine on posterior margin, merus about 4, carpus about 7 denticulate spines. Propod, ovately triangular, as long as basos, width ½ length, 4 strong denticulate spines on posterior margin, several rows of spines on surface distally. Dactylos strong, ½ propod length, has 2 strong denticulate spines on posterior margin, a strong end spine-claw. Second: Basos and carpus subequal in length, merus slightly shorter, ischium still shorter; propod almost as long as merus plus carpus; segments furred; dactylos ½ propod length, has strong end-claw, a few fine setae. Ischium has 2 strong spine-setae on posterior margin, merus 4, carpus 6; propod has 2 very strong ones on posterior margin, about 4 rows of 2–3 slimmer spines down median surface. Third: Like 2nd. Fourth-Sixth: Like 7th. Seventh: Basos and propod subequal, ischium, merus and carpus successively shorter, carpus about ½ propod, all furry with a few fine setae on margins; dactylos claw truncate on left peraeopods, sharp on right.
Pleopods. First: Peduncle has 3 coupling spines; one ramus about ½ length other which has 4 long end setae. Second: Rami subequal, subrectangular, strongly fringed with plumose setae. Third: Ovate-lanceolate, one ramus little larger than other, a few fine marginal setae; one stronger end seta on shorter ramus.
Uropods. Furry; subtriangular, ramus very short, ovate-triangular, has 3 plumose setae distally; secondary about 2/3 as long, narrow, has an equally long and slightly curved strong end spine.
Material Examined: Station BOL (VUZ. 43), 1 female, ovigerous, 4 9 mm long, 1.2 mm wide.
Holotype: Slides Oc. 6.
Distribution : Cook Strait.
Discussion: This specimen is very close to Ohlin's Pseudidothea bonnieri, the type of the genus and family. However, there are sufficient small differences, I feel, to warrant establishing a separate species—the second in the family—and the finding of a male may reveal further differences in the pleopods from P. bonnieri.
The most significant features are the end setae of the main uropod ramus: the lack of tubercles on the peraeopods; and the strong spination of the second antennae.
Sub-Order Asellota
Family Parasellidae
Group Ianirini
Iathrippa longicauda (Chilton), 1884. (Figs. 92–107).
Janira longicauda Chilton, 1884: 250, pl. 18, fig. 2a.
Thomson, 1889: 265–266.
Tattersall, 1921: 200, pl. 1, fig. 6.
Ianira (Iathrippa) longicauda, Nordenstam, 1933: 173–176, text-figs. 40 a–h.
Iathrippa longicauda Nierstrasz, 1941: 286.
Diagnosis (Female) : Anterolateral angles of cephalon more or less rounded, not significantly produced anteriorly; rostrum triangulate, reaching distal end of 3rd peduncle segment of antenna 2. Epimeral plates visible dorsally, between lateral angles of segments 2–4 of body, posterodistally on segments 5–7, Pleotelson margins smooth, setose, slight
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indication distally of rounded median lobe. Uropods longer than pleotelson, rami somewhat lanceolate, inner the longer.
Body. Somewhat flattened, white in preserved specimen. Lateral margins of body setose.
Antennae. First: Reaches ½ along 5th peduncle segment of antenna 2; distal flagellar segments have each a flaccid sensory seta; flagellum of 15 segments, segments not especially widened. Second: 1st 4 peduncle segments together a little shorter than 5th, have several strong spines and setae; 5th ¾ length 6th; 5th and 6th have 1–2 long spines on each margin, setae; 1st flagellar segment nearly ½ length last peduncle segment; flagellum of 55 or more segments; accessory scale on 3rd peduncle segment, reaches end of 4th, has 4 end spines, setae.
Mouth parts. Maxilliped: Has 3 coupling spines; endite distal margin has 8–9 plumose setae; 7 large bush-setae, small spine on inner distal angle, longer one on rounded outer angle. Palp, 1st 3 segments as wide as endite, inner distal angles setose, 4th and 5th segments slender, distally setose, 5th 1/3 length 4th; 4th as long as 2nd and 3rd combined. Maxilla 1: Inner plate has 4 strong setae, fine bristles; outer has 11 denticulate spines. Maxilla 2: Outer plate lappets have 4 end setae each; inner has numerous end setae. Mandibles: Lacinia present; spine row of 9 denticulate spines; mandibular process long, not narrowing but truncate, has upper angle produced a little in tooth, lower has slender spine and 5–6 plumose setae; a few minute teeth on surface. Palp of 3 segments, 1st and 3rd subequal, about 2/3 length 2nd: 1st has about 3 setae on distal angle; 2nd has about 7 strong denticulate spines, comb-scales on surface; 3rd has long terminal spine, row of about 20 denticulate spines on concave margin.
Peraeopods. First: Carpus and propod subequal, carpus broader but not noticeably ovate, width not 1/3 length; posterior margin has 11–12 spines, seta or two, otherwise entire; propod posterior margin has 7–8 spines, otherwise entire. Dactylos has 2 claws, setae. Seventh: Carpus barely shorter than propod. has about 3 spines, setae, anteriorly; propod has about 5 spines; dactylos as in 1st. Others: All dactyli have 2 claws.
Pleopods. Third has exopodite slightly longer than endopodite, of 2 segments; endopodite has 2 plumose setae distally on inner margin, one on outer.
Operculum. Ovate, distally rounded, margins have short fine setae.
Uropods. Outer ramus about 2/3 length inner; peduncle ½ inner, widening distally; peduncle and rami all strongly spined and setose.
Material Examined: Station GUL (VUZ. 54), 1 female, 8.5 mm (Slides Oc. 4).
Distribution: Cook Strait; Lyttelton Harbour (Chilton); "Terra Nova" Station 96, 7 miles E. of North Cape, 70 fathoms, bottom fauna, 1 ovigerous female, 4 5 mm (Tattersall, 1921); Campbell Islands, Falkland Islands, S. Georgia, Magellan Straits, W. Chile (cf. Nordenstam, 1933).
Discussion : This specimen agrees quite well with Chilton's original description, and with Nordenstam's supplementary details. Tattersall's figure is a little generalised and even inaccurate since he shows the epimeral plates as part of the lateral margins of the segments. It should be noted, however, that the dactyli in this specimen all have 2 claws whereas Nordenstam mentions 3.
I have followed Nierstrasz rather than Nordenstam in generic classification, not because of any strong views on the subject but because Nierstrasz's is the more recent paper.
Group Jaeropsini
Genus Jaeropsis Koehler
Jaeropsis palliseri n.sp. (Figs. 67–73, 108–117).
Diagnosis: Eyes near lateral margin. Anterolateral angles of cephalon bluntly rounded, not significantly produced anteriorly. Rostral process subrectangular, anterior margin somewhat sinuate. Maxilliped endite has 5 coupling spines. Distal angle of maxilliped palp 2nd segment not produced. Pleotelson margins smooth, entire. Exopodite of uropod has 1 segment. Body has purplish-brown pigmentation with white mottling on all segments, posterolateral portion of head and lateral angles of body somites unpigmented.
Body. Animal elongate, flattened, dorsally smooth, lacking noticeable setae. Cephalon wider than long. Frontal margin has shallow lateral concavities separated by central shallow, but more anteriorly produced, concavity, into which rostral projection fits. Eyes dorsal, a
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little in front of halfway. Peraeon has no epimeral plates visible in dorsal view. 1st and 2nd somites equally long, 5th shortest. Pleotelson wide, shield-like. Posterior median projection semi-acute, does not reach distally as far as tips of uropods.
Antennae. First: Of 6 segments, 1st as long as other 5, twice as wide, has scattered fine setae, 2 plumose sensory setae on distal angle. Last 2 segments have 2 elongate flaccid sensory setae each, a few fine setae. Second: Peduncle 5th segment about ¾ length 6th, both distally expanded on inner margin; outer and end margins and surface of 6th have fine setae; 6th segment of peduncle ¾ length 1st flagellar segment which is more than twice length remaining 5 flagellar segments; segments all setiferous, 1st especially on surface and outer margin.
Mouthparts. Maxilliped: Palp of 5 increasingly narrower segments, 1st short, 1/3 length 2nd, ¼ length 4th; 3rd almost twice length 1st and 5th; inner margins of 3rd and 4th bristled, a few setae especially on end of 5th. Endite has only about one distinct spine on inner concavity of end margin, but about 5 spine-teeth. Maxilla 1: Inner plate has 4 apical setae, outer 11 denticulate spines. Maxilla 2: Outer plate lappets have 4 apical setae each, inner plate also has 4. Mandible: Lacinia absent. Incisive part has 5–6 teeth, setal row of 9 setae; molar long and needle-like, damaged in mounted appendage. Palp of 3 segments, 1st slightly longer than subequal 2nd and 3rd; 2nd has 5 plumose setae distally, 3rd has 10–11 along inner margin.
Peraeopods. First: Dactylos has 2 claws, propod has 5 spines on posterior margin, most of margin and distal ¼ of carpus posterior margin finely tooth-combed. Seventh: Dactylos has 3 claws, propod posterior margin has 6 spines, is finely tooth-combed. Others: Have 3 claws like 7 th.
Pleopods. 1st in male has produced rounded posterolateral angles, medially produced setiferous end margin.
Uropod. Peduncle, wide, subrectangular, with rounded angles, end margin setose, medially excavate with small scale-like rami, both rami distally setose.
Material Examined: Station BOL (VUZ. 43), Holotype male, length 5.3 mm; width 1.4 mm.
Holotype: Slides Oc. 3.
Distribution : Cook Strait.
Discussion: According to Chilton (1912), young specimens of neo-zelanica (? = curvicornis; cf. Stebbing, 1905: 51–52, pl. XI.C) have several serrations on the pleon margins, older specimens have one serration. Since his material came from several localities, I am inclined to believe that he had more than one species; in any event, it appears that his material was different from the species described above. Nearest to J. palliseri are J. paulensis and J. lobata; the latter appears to be distinct in rostral process and, by inference from its possible identity with J. dubia (Menzies, 1951), in the uropods and other features.