New species of aetideopsis sars and bradyidius giesbrecht (copepoda: Calanoida) from the southern hemisphere

New Zealand Journal of Marine and Freshwater Research ISSN: 0028-8330 (Print) 1175-8805 (Online) Journal homepage: http://www.tandfonline.com/loi/tnzm20 New species of aetideopsis sars and bradyidius giesbrecht (copepoda: Calanoida) from the southern hemisphere Janet Bradford To cite this article: Janet Bradford (1969) New species of aetideopsis sars and bradyidius giesbrecht (copepoda: Calanoida) from the southern hemisphere, New Zealand Journal of Marine and Freshwater Research, 3:1, 73-97, DOI: 10.1080/00288330.1969.9515279 To link to this article: https://doi.org/10.1080/00288330.1969.9515279 Published online: 29 Mar 2010. Submit your article to this journal Article views: 51 View related articles Citing articles: 6 View citing articles Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalinformation?journalcode=tnzm20 Download by: [37.44.194.11] Date: 05 December 2017, At: 03:40

1969] 73 NEW SPECIES OF AETIDEOPSIS SARS AND BRADYIDIUS GIESBRECHT (COPEPODA: CALANOIDA) FROM THE SOUTHERN HEMISPHERE JANET BRADFORD New Zealand Oceanographic Institute, Department of Scientific and Industrial Research, Wellington (Received for publication 7 June 1968) SUMMARY Three new species of calanoid copepod in the family Aetideidae are described, two in Aetideopsis Sars, 1903 and the third in Bradyidius Giesbrecht, 1897. One Aetideopsis species is from off South West Africa (south-east Atlantic), the remaining species are from the east coast of New Zealand (south-west Pacific). The genus Pseudaetideus Wolfenden, 1904 is merged with Aetideopsis. INTRODUCTION Specimens of Aetideopsis and Bradyidius (Family Aetideidae) were found in deep hauls (200-600 m) at Kaikoura, New Zealand, and another Aetideopsis from 100-300 m off South West Africa was made available. Both sexes were captured and they have proved to be different from any described species. Difficulties were found in separating males of the genera Aetideopsis, Pseudaetideus, and Bradyidius. This led to a reappraisal of these genera within the Aetideidae. SYSTEMATICS Genus Aetideopsis Sars, 1903 Twelve species of Aetideopsis have previously been described: A. rostrata Sars, 1903; A. multiserrata (Wolfenden, 1904); A. antarctica (Wolfenden, 1908); A. minor (Wolfenden, 1911); A. pacifica Esterly, 1911; A. divaricata Esterly, 1911; A. nasuta (With, 1915); A. modesta (With, 1915); A. trichecus Vervoort, 1949; A. divergens Tanaka, 1957; A. cristata Tanaka, 1957; A. retusa Grice and Hulsemann, 1967. Amongst these species the badly described A. divaricata is considered by Vervoort (1963, p. 123-4) to be closely allied to if not identical with A. trichecus and he also (1957, p. 53) considers the briefly characterised A. pacifica is probably identical with A. rostrata. Farran (1926) equates A. nasuta with A. multiserrata. N.Z. Jl mar. Freshwat. Res. 3: 73-97.

74 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. Aetideopsis tiimorosa n. sp. Aetideopsis sp.: Bradford, in press. FEMALE: Total length 2.60 mm. Cephalothorax, viewed dorsally (Fig. 1) is similar to that of A. rostrata. Abdomen occupies about total length of animal, head and first thoracic segment fused, thoracic segments 4 and 5 separate. Postero-lateral thoracic borders extended backwards and slightly upwards in long points which almost reach genital segment hind border. Rostrum (Fig. 3) large with U-shaped gap between slightly diverging points. Abdomen 4-segmented. Lateral swellings on genital segment (Fig. 1) situated anteriorly and moderate ventral swelling is central (Fig. 2). Furca slightly longer than wide. Antenna I, normally at right angles to the body in preserved specimens (Fig. 1), almost reaches posterior border of second abdominal segment. FlGS 1-2 Aetideopsis tumorosa female. 1 dorsal view; 2 lateral view. Scale mark 1.0 mm.

1969] BRADFORD NEW SPECIES OF Aetideopsis 15 FIGS 3-8 Aetideopsis tumorosa female. 3 rostrum; 4 antenna II; 5 mandibular palp; 6 maxilla I; 7 maxilla II; 8 maxilliped. Scale mark 0.1 mm.

76 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. Antenna II (Fig. 4), mandibular palp (Fig. 5), maxilla I (Fig, 6), maxilla II (Fig. 7) and maxilliped (Fig. 8) formed in much the same way as in A. rostrata apart from small differences in seta numbers. Swimming leg I (Fig. 9) has 1-segmented endopod, 3-segmented exopod. Endopod with perfectly straight sides, spinules on anterior surface. Seta on basipod 2 straight, lying on anterior surface. External edge spine on first exopod segment extends past second segment while spine on second segment does not reach end of third segment. Swimming leg II (Fig. 10) has 1-segmented endopod without any sign of fusion line. Anterior exopod surface has several glandular pores and a row of spinules along distal border of second segment. Terminal spine carries externally approximately 48 closely placed sharp teeth. FIGS 9-13 Aetideopsis tumorosa female. 9 leg I; 10 leg II; 11 leg III; 12- leg IV; 13 part leg TV terminal exopod spine. Scale mark 0.1 mm.

1969] BRADFORD NEW SPECIES OF Aetideopsis 77 Swimming legs III and IV (Figs 11, 12) have bo!h rami 3-segmented. First endopod segment of third leg not completely separate from second, as externally joints are fused. Anterior surface legs III and IV exopods with glandular pores; distal row of spinules on second exopod segment. Terminal spine on exopod has between 50 and 60 fine, sharp, closely packed external teeth (Fig. 13). Swimming leg V absent. MALE: Total length 2.60 mm. In general, shape and size similar to female. Head and first thoracic segment completely fused, thoracic segments 4 and 5 partially fused with posterior corners extended backwards into points (considerably shorter than in female) which scarcely extend past first abdominal segment (Fig. 14). Fics 14 18 Aetideopsis tumorosa male. 14 dorsal view, scale mark 1.0 mm. 15 antena II; 16 mandibular palp; 17 maxilla I; 18 maxilliped. Scale mark 0.1 mm.

78 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. Rostrum bifurcate, smaller than in female. Abdomen occupies 1/3.7 of animal's total length. Antenna I at right angles to body in holotype specimen, does not reach the first free thoracic segment when held back; 23-segmented with eighth, ninth, and tenth fused. Antenna II similar to that of female (Fig. 15) but with fewer setae. Mandibular palp (Fig. 16) has reduced number of setae on second basipod and first endopod segment. Second endopod segment expanded distally. Maxilla I (Fig. 17) has reduced setation: no spines on first inner lobe nor setae on second inner lobe. Setae on all other lobes similar to female although there appears to be a greater number on the male first outer lobe. Maxilla II much reduced, % length of female appendage. Maxilliped slender but smaller than that of female. Setation as in Fig. 18. Swimming leg I (Fig. 19) segmented and formed as in female except that it is more slender and exopod outer edge spines are much shorter. Swimming leg II (Fig. 20) has the 2 endopod joints clearly visible although there is some sign of fusion externally. Apart from exopod being slightly squatter and terminal spine shorter with fewer teeth (approximately 39), this limb otherwise resembles that of the female. Swimming legs III and IV (Figs 21, 22) similar to female's except that they are slightly more slender and have terminal exopod spine with between 40 and 50 teeth, leg IV second exopod segment does not have anterior distal row of spinules, and separation of all 3 endopod segments in both legs III and IV is complete. Swimming leg V (Fig. 23) biramous on both sides, of approximately equal length, not passing the furca. Both legs have 2 basal segments and rudimentary 1-segmented endopod, tapering on the left with a small seta at the tip, blunt on the right. Right leg first 2 exopod segments fused while third segment is expanded distally bearing long tapering stout spine. Left exopod 3-segmented with small hirsute terminal segment bearing 2 distal spinules, and patch of hairs on distal part of second segment. HOLOTYPE: The holotype, a female, is deposited in the collection of the New Zealand Oceanographic Institute, Wellington, Reg. No. 45. PARATYPES: Pairs of female specimens have been deposited at the Dominion Museum, Wellington (Cat. No. Cr. 1806); the British Museum (Natural History) (B.M. Reg. No. 1968. 3.18.1.); and the Smithsonian Institution (Cat. No. USNM 122638). The remaining five female paratypes have been deposited in the collection of the New Zealand Oceanographic Institute, Wellington, Reg. No. 53, while the male paratype has Reg. No. 52.

1969] BRADFORD NEW SPECIES OF Aetideopsis 79 19 FIGS 19-23 Aetideopsis tumorosa male. 19 leg I; 20 leg II; 21 leg III; 22- leg IV; 23 leg V. Scale mark 0.1 mm. MATERIAL EXAMINED: Type material came from one sample collected at Kaikoura, New Zealand on 5.V.65. Descriptions and drawings were made from the female holotype and one paratype specimen and the male paratype. Females in the type lot measured from 2.50 mm to 2.77 mm. An additional male from NZOI Sta. G142, 174 00.8' E, 42 25'S, 250-500 m was 2.40 mm long.

80 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. TYPE LOCALITY: Kaikoura, New Zealand, 173 52'E, 42 26'S (see Fig. 75). HABITAT: The largest number were caught in plankton hauls at 200-500 m and 0-600 m but hardly ever in hauls at 0-200 m. DISTRIBUTION: AS well as being recorded at the type locality A. tumorosa has been found at NZOI Sta. B 120, 170 15'E, 53 26.35' S (see Fig. 75) and Portobello Marine Biological Sta. Mu 67/62S., 45 54' S, 171 05'E. DEVELOPMENTAL STAGES: Copepodite stages V female (2.20 mm, Fig. 24), V male (2.50 mm, Figs 25, 26), IV (1.80 mm, Fig. 27) and III (1.30 mm, Fig. 28) were also found. The rostrum is visible from the dorsal surface in all developmental stages but is more prominent in the younger stages. Posterior thoracic extensions appear at stage IV. DISCUSSION: Aetideopsis tumorosa differs from all previously described species in the shape of the genital segment, the form of the first swimming leg endopod which has no outer tubercle, and the 1-segmented female second leg endopod. The male of A. tumorosa is very similar to those males already described: A. multiserrata (see Tanaka 1957); A. divergens Tanaka, 1957; A. cristata Tanaka, 1957. A. tumorosa differs most obviously in that the first antenna does not reach past the proximal border of the second thoracic segment. The specific name refers to the swollen nature of the genital segment. FIGS 24-28 Aetideopsis tumorosa copepodites. 24 stage V female; 25 stage V male; 26 leg V stage V male; 27 stage IV; 28 stage III. Scale mark Fig. 26, 0.1 mm, remainder 1.0 mm.

1969] BRADFORD NEW SPECIES OF Aetideopsis 81 Aetideopsis carinata n. sp. 1964. Aetideopsis sp.: Unteriiberbacher, p. 21, PI. 28. FEMALE: Total length 2.96 mm. Cephalothorax, viewed dorsally (Fig. 29), has pronounced lateral extensions covering antenna II. Head produced into a blunt keel dorsally and anteriorly. Abdomen occupies just under \ of animal's total length, head and first thoracic segment fused, thoracic segments 4 and 5 only partially separate. Postero-lateral thoracic borders flare outwards and backwards into points which reach halfway down genital segment. Rostrum (Fig. 31) large, directed slightly posteriorly, with distinct angle between the points and common base. Abdomen 4-segmented. Lateral genital segment swellings (Fig. 29) central but anterior ventrally (Fig. 30). Antenna I (Fig. 30) reaches third or fourth abdominal segment; 24- segmented with eighth and ninth fused. Antenna II (Fig. 32) endopod slightly shorter than exopod. First and second exopod segments separate, setae placed as in figure. Mandibular palp (Fig. 33) second basipod segment with 1 seta, endopod missing in type specimen but paratype specimen has 2 setae on first segment, 8 on second. Maxilla I (Fig, 34), maxilla II (Fig. 35) and maxilliped (Fig. 37) are similar to those of A. tumorosa except for slight differences in setae numbers. Swimming leg I (Fig. 36) has 1-segmented endopod of usual type with external spinule-bearing projection, 3-segmented exopod. External edge spine on first exopod segment extends past second segment while spine on second segment reaches distal border of third segment. Swimming leg II (Fig. 39) has 1-segmented endopod without any sign of fusion line. Anterior exopod surface bears several glandular pores. Terminal spine carries externally approximately 26 closely placed, sharp teeth. Swimming leg III (Fig. 40), endopod 2-segmented without any sign of fusion line between first 2 segments. Exopod 3-segmented, anterior surface with glandular pores; terminal spine has 29 teeth. Swimming leg IV (Fig. 41) with both branches 3-segmented, otherwise as leg III. Terminal exopod spine with 30 teeth (Fig. 38). Swimming leg V absent. MALE: Total length 2.40 mm. In general, shape and size similar to female. Head and first thoracic segment completely fused, thoracic segments 4 and 5 partially fused with posterior corners extended backwards into short points which reach posterior border first abdominal segment (Fig. 42). Rostrum (Fig. 44) similar to that of female but smaller. Sig. 6

82 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. FIGS 29-36 Aetideopsis carinata female. 29 dorsal view; 30 lateral view; Scale mark 1.0 mm. 31 rostrum; 32 antenna TI; 33 mandible; 34 maxilla I; 35 maxilla II; 36 leg I. Scale mark 0.1 mm.

1969] BRADFORD NEW SPECIES OF Aetideopsis 83 37 FIGS 37-41 Aetideopsis carinata female. 37 maxilliped; 38 part leg IV terminal exopod seta; 39 leg II; 40 leg III; 41 leg IV. Scale mark 0.1 mm.

84 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. Abdomen (Fig. 42) occupies 1/3.5 animal's total length. Antenna I reaches just past third thoracic segment (Fig. 43); 23- segmented with eighth, ninth, and tenth, fused. Antenna II (Fig. 45) similar to female's but with fewer setae. Mandibular palp (Fig. 46) has reduced number setae on first endopod segment and second endopod is expanded distally in usual fashion. Maxilla I has reduced setation, similar to A. tumorosa but with slightly different number of setae (Fig. 47). Maxilla II much reduced. Maxilliped smaller than that of female, setation as in Fig. 48. Swimming leg I (Fig. 49) segmented and formed as in female except exopod outer edge spines shorter. FIGS 42-49 Aetideopsis carinata male. 42 dorsal view; 43 lateral view; scale mark 1.0 mm. 44 rostrum; 45 antenna II; 46 mandibular palp; 47 maxilla I; 48 maxilliped; 49 leg 1. Scale mark 0.1 mm.

1969] BRADFORD NEW SPECIES OF Aetideopsis 85 Swimming leg II (Fig. 50) has endopod joints fused but fusion line visible. Exopod terminal spine has approximately 30 teeth but otherwise limb similar to that of female. Swimming legs III and IV (Figs. 51, 52) have both rami 3-segmented and terminal exopod spines have increased number of teeth (30, 33 respectively) compared with female limbs. Swimming leg V (Fig. 53) biramous on both sides, right leg exopod passing furca by y 3 length of terminal segment. This leg very like that of A. tumorosa but right leg first basipod larger in A. carinata and left leg second exopod segment bears 2 spinules distally, as well as hairs. HOLOTYPE: The holotype, a female, is deposited at the South African Museum (Cat. No. SAM A12639). 53 FIGS 50-53 Aetideopsis carinata male. 50 leg II; 51 leg III; 52 leg IV; 53 leg V. Scale mark 0.1 mm.

86 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. PARATYPES: One female (Cat. No. SAM A12641) and one male (Cat. No. SAM A12640) have been deposited at the South African Museum; one female is in the collection of the New Zealand Oceanographic Institute, Wellington, Reg. No. 55; one female and one male are at the British Museum (Natural History) (B.M. Reg. No. 1968. 4.30.1. ( 9 ) and B.M. Reg. No. 1968. 4.30.2. MATERIAL EXAMINED: Type material came from one sample collected off the coast of South West Africa 23.viii.63. Descriptions and drawings were made from the female holotype and a paratype, and a male paratype. Females in the type series measured from 2.60 mm to 2.80 mm. An additional male measured 2.33 mm. TYPE LOCALITY: South-east Atlantic Ocean off the coast of South West Africa, 21 09' S, 12 44' E (see Fig. 76). HABITAT: The type specimens were caught in a vertical N70 net haul from 0-300 m although Unteriiberbacher (1964) stated that this species was never caught above 100 m. DISTRIBUTION: The known distribution of A. carinata is off the southwest coast of Africa seaward from the continental slope. A few specimens intrude onto the shelf (Unteriiberbacher 1964, PI. 10 (a)). DISCUSSION: The Aetideopsis carinata female differs from all other species in several respects: the notch between the rostral points is square in shape, swimming leg III has a 2-segmented endopod, and the thoracic segments 4 and 5 are not completely separate. Males are more like other members of the genus but are distinguished by a 1-segmented endopod on swimming leg II and by the left swimming leg V having the second exopod segment bearing 2 spinules distally as well as hairs. The specific name refers to the keeled nature of the female head. Genus Bradyidius Giesbrecht, 1897 The validity of this name over Undinopsis Sars has been much in doubt and two recent workers, Brodsky (1950) and Tanaka (1957) have not followed the opinion of Schmitt (in Wilson 1950, pp. 172-3) which I am accepting. Five species of Bradyidius have been described: B. bradyi (Sars, 1903)*; B. similis (Sars, 1903); B. angustus (Tanaka, 1957); B. tropicus (Wolfenden, 1905;) B. pacificus (Brodsky, 1950); B. arnoldi Fleminger, 1957. Aetideus sp. (Brodsky, 1955) with spines on the endopod of at least the second leg, and large external exopod spines on the same limb, is also an example of Bradyidius. *See Matthews (1964) for discussion of priority of specific name bradyi over armatus.

1969] BRADFORD NEW SPECIES OF Aetideopsis 87 Bradyidius spinifer n. sp. Bradyidius sp.: Bradford, in press. FEMALE: Total length 2.74 mm. Cephalothorax viewed dorsally similar in shape to that of B. bradyi. Abdomen less than \ total length. Head and first thoracic segment fused but the line of fusion clearly visible. Fourth and fifth thoracic segments incompletely fused laterally and postero-lateral thoracic borders extend backwards and upwards into acute points which do not quite reach genital segment posterior border (Fig. 54). Rostrum represented by two medium-sized points. Abdomen 4-segmented, with genital segment longest but little swollen either laterally or ventrally. Antenna I almost reaches posterior border third thoracic segment; 24- segmented, eighth and ninth fused. All of numerous setae of annulate type. FIGS 54-57 Bradyidius spinifer female. 54 lateral view; Scale mark 1.0 mm. 55 antenna IT; 56 mandible; 57 maxilla T. Scale mark 0.1 mm.

88 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. Antenna II (Fig, 55) second endopod segment with 2 extra setae on internal protuberances. Mandibular palp (Fig. 56) has 2 setae on second basipod. First endopod segment has 3 setae and second segment has 13 setae of which 3 are very small. Maxilla I (Fig. 57) first inner lobe covered with small spinules and has 8 stout, sparsely plumose, apical spines, 2 longer proximal spines and 4 setae. Second inner lobe has 5 setae, third inner lobe covered in fine spines and has 4 setae. First outer lobe has 9 large setae, second outer lobe is naked. Second basipod has 4 setae and endopod has approximately 15 setae. Exopod has 10 setae. Maxilla II (Fig. 58) first 4 lobes ornamented with fine spines, first 5 lobes each with 3 spinelike setae. Sixth lobe appears to have 1 seta. Exact number of seta on endopod could not be determined but is probably 5. FIGS 58-60 Bradyidius spinifer female. 58 maxilla II; 59 maxilliped; 60 leg I. Scale mark 0.1 mm.

1969] BRADFORD NEW SPECIES OF Aetideopsis 89 Maxilliped (Fig. 59) first basal segment stocky, width about \ length. Second basal segment more slender, about % longer than first basipod. Setae arranged as in figure. Swimming leg I (Fig. 60) has 1-segmented endopod and 3-segmented exopod. External lump on endopod covered with spinules and second basipod seta is densely plumose in region of lump. Anterior surface of endopod has a few spinules. Each external exopod spine longer than length of its segment. Swimming leg II (Fig. 62) has 2-segmented endopod, 3-segmented exopod. Both endopod segments have complete posterior surface covered in many very small spinules. External exopod spines are very stout, bordered with fine hairs. Terminal spine has 20 widely spaced, elongate teeth (Fig. 61). Second exopod segment anterior surface laterodistal corner has group of small spines. Swimming legs HI and IV (Figs 63, 64) have both rami 3-segmented. Posterior endopod surfaces entirely covered in small spinules. Both pairs of legs almost similar with spine patch on second exopod segment as in second leg. Leg IV slightly longer than leg III, terminal spine with 24 teeth on leg IV but 21 on leg III. Swimming leg V absent. MALE: Total length 1.96 mm. Male considerably smaller than female and less robust. Head and first thoracic segment fused although traces of fusion line may be seen. As in female, thoracic segments 4 and 5 incompletely fused and posterior corners extend in sharp points about halfway down second abdominal segment (Fig. 65). Rostrum bifurcate, of similar proportions to that of female. Abdomen occupies over \ total length of animal. Antenna I, at right angles to body in type specimen, reaches past third abdominal segment when held back; 23-segmented with eighth, ninth, and tenth fused. Antenna II (Fig. 66) similar to that of female although there are no extra setae on second exopod segment. Mandibular palp (Fig. 67) setation reduced, especially on second basipod and endopod. Second endopod segment expanded distally. Maxilla I (Fig. 68) has no spines on first or second inner lobes. Two setae on third inner lobe. First outer lobe has 4 large setae, none on second outer lobe. Remainder of limb as in female but endopod has 4 fewer setae in male. Maxilla II very reduced. Maxilliped (Fig. 69) smaller than in female with slightly reduced number of setae. Swimming legs segmented as in female. Swimming leg I (Fig. 70) differs in having small external spine on first exopod segment.

90 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. MAAM FIGS 61-64 Bradyidius spinifer female. 61 part leg IV terminal exopod spine; 62 leg II; 63 leg III; 64 leg IV. Scale mark 0.1 mm.

1969] BRADFORD NEW SPECIES OF Aetideopsis 91 70 70 FIGS 65-74 Bradyidius spinifer male. 65 ventral view; Scale mark 1.0 mm. 66 antenna II; 67 mandibular palp; 68 maxilla I; 69 maxilliped; 70 leg I; 71 leg II; 72 leg III; 73 leg IV; 74 leg V. Scale mark 0.1 mm. 74

92 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. Swimming leg II (Fig. 71) similar to female although no spinules found on posterior surface of first endopod segment and terminal exopod spine has more teeth (27). Swimming legs III and IV (Fig. 72, 73) remnants show that first endopod segment leg III has no posterior spinules although leg IV has. Swimming leg V (Fig. 74) uniramous, equal, 5-segmented on both sides. Right leg has 2 small basal segments and 3 narrowed segments the last of which tapers. Left leg (which was lost whilst being mounted permanently) has 2 longer basal segments, 2 elongate segments, and a small apical segment covered with hairs. HOLOTYPE: The holotype, a female, is deposited in the collection of the New Zealand Oceanographic Institute, Wellington, Reg. No. 46. PARATYPE: The paratype, a male, is deposited in the collection of the New Zealand Oceanographic Institute, Wellington, Reg. No. 54. MATERIAL EXAMINED: Only the holotype and paratype collected at Kaikoura, New Zealand, on 29.X.64. were available for description. TYPE LOCALITY: Kaikoura, New Zealand, 173 52'E, 42 26'S {see Fig. 75). HABITAT: B. spinifer was captured once in a vertical haul 0-600 m which touched the bottom. It is deduced that this species, like B. bradyi (Sars, 1903), is benthic. DISCUSSION: Bradyidius spinifer differs from all previously described species in the extremely dense spinules on the endopods of legs II to IV. The male differs from B. angustus, in which the fifth swimming legs are very similar, in the much longer posterior extensions of the thorax which reach over % down the second abdominal segment. The specific name refers to the very spinous nature of the endopods. RELATIONSHIPS BETWEEN Chiridius, Aetideopsis, Bradyidius AND Pseudaetideus Similarities between these genera have been acknowledged and there has been much confusion about their limits. According to Vervoort (1952a, 1952b) Chiridius is characterised by the absence of a rostrum, Aetideopsis by separate fourth and fifth thoracic segments, and Bradyidius is noted for the minute spinules on the leg II to IV endopods (Tanaka 1957, p. 45) and more especially for the numerous long annulate setae on antenna I (Vervoort 1952c). From the above descriptions of new species of Aetideopsis and Bradyidius it is evident that the generic descriptions (Vervoort 1962a, 1952c) must be broadened to include all the species.

1969] BRADFORD NEW SPECIES OF Aetideopsis 93-35 e 40' 45 50s e S NEW. ZEALAND / SOUTH \.ss J* ^-^_y ^ Stewart Snares 0 Auckland Is Campbell U ^ M ^ NORTH I. rkaikoura Portobello + Stn 1. B120 Chatham Is. Bounty 1. South West Pacific 55 165 170 175 E180 W 175 FIG. 75 Map showing the locality where Aetideopsis tumorosa and Bradyidius spinifer were found.

94 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. 0 V / ) AFRICA -20 \ V Wai vis \ Bav South \ Atlantic \ Capetowi 40 S SOUTH / AFRICA / 20 E Indian Ocean 40 FIG. 76 Map showing locality where Aetideopsis carinata was found. Aetideopsis may have the fourth and fifth thoracic segments almost fused as in A. carinata and the second leg endopod need not be 2- segmented as both A. tumorosa and A. carinata indicate. The genus Aetideopsis, in a wider sense, would hold Euchaeta armata Boeck, 1872 which has been placed in several genera. Sars (1903), who recognised it as an aetideid, placed it in Chiridius but subsequently Wolfenden (1904) erected a new genus Pseudaetideus for this single species which he called P. armatus. The original description by Boeck (1872) is very brief. Sars (1903) gave detailed drawings but missed one salient point picked up by With (1915) and Matthews (1964) who both figured Chiridius armatus (Boeck 1872) with thoracic segments 4 and 5 fully or partially separate. Personal observations of specimens from Biologisk Stasjon, Blomsterdalem, Norway, confirm the almost complete separation of thoracic segments 4 and 5 and indicate the structure of exopod terminal spine teeth which are of Aetideopsis type (Vervoort 1957, p. 52), not as in Chiridius and Aetideus which have no lamella between wider spaced teeth. Lateral exopod spines are the same as in other Aetideopsis. The separation of thoracic segments 4 and 5, the form of the male fifth legs, the large number of small, acute teeth joined by a lamella on the terminal exopod spine, and a bifurcate rostrum are sufficient in my opinion to place Euchaeta armata Boeck, 1872 in Aetideopsis as A. armata although the rostrum is small and the frontal organ is not visible from the back.

1969] BRADFORD NEW SPECIES OF Aetideopsis 95 Amongst the males of Bradyidius and Aetideopsis there is some overlap in the form of the fifth swimming legs and in spinulation of swimming leg endopods. Aetideopsis is characterised by a biramous leg V with rudimentary 1-segmented endopods one of which is rounded, the other tapering. Bradyidius exhibits two types of fifth leg, one uniramous, the other very similar to that of Aetideopsis and sometimes with one endopod 2-segmented (Fleminger 1957). Incomplete fusion of the fourth and fifth thoracic segments in B. pacificus and B. spinifer provides another link with Aetideopsis. The position of B. similis was re-examined with the help of material, identified by Sars, from the Zoologisk Museum, Oslo. Sars' conclusions are substantiated from the general form and the fine, widely spread teeth on the terminal exopod spine; this species, like B. pacificus, has no posterior spinules on swimming-leg endopods. The fact that the two Antarctic species of Aetideopsis, A. minor and A. antarctica, have fine spinules on the swimming leg endopod posterior surfaces (personal observation) diminishes the usefulness of this character as an indication of the genus Bradyidius. Points arising from this discussion have been included in new generic definitions modified from Vervoort (1952a, b). Genus Aetideopsis Sars, 1903 Females resemble Aetideus but front part of head has prominent frontal organ usually visible from back. Head and first thoracic segment fused or indistinctly separated. Thoracic segments 4 and 5 usually completely separate. Rostrum distinctly 2-pointed with deep incision between points. Postero-lateral thoracic borders acutely pointed. Antenna I, 24-segmented with annulated setae and club-shaped appendages, not elongate on distal segments. Maxilliped second basipod longer than first. Endopod leg I, 1-segmented; leg II, 1- or 2-segmented; leg III, 2- or 3-segmented; all other branches 3-segmented. All leg I exopod segments with external spine. Terminal exopod spine usually with numerous sharp, closely placed teeth along outer edge. Exopod external spines moderately large, intermediate between Aetideus and Bradyidius, bordered with fine hairs unlike Aetideus. Males more slender with comparatively longer abdomen. Leg V in known males always biramous with 1-segmented endopods; tapering on left, rounded on right. Right exopod 2-segmented; left 3-segmented, last segment small, hirsute. Genus Bradyidius Giesbrecht, 1897 Females with strongly built bodies. Head and first thoracic segment fused. Head broadly rounded and provided with bifurcate rostrum. Rostral points acute, pointing downwards. Thoracic segments 4 and 5 usually completely fused, postero-lateral thoracic borders produced into

96 N.Z. JOURNAL OF MARINE & FRESHWATER RESEARCH [MAR. strong, acute, backward-directed points. Abdomen short, anal segment short, furca as long as wide. Antenna I usually as long as or shorter than cepholothorax, 24-segmented with many club-shaped appendages and thickened annulate setae which are elongate on distal segments. Antenna II exopod and endopod almost equal. Maxilliped second basipod segment elongate. Endopod leg I, 1-segmented; leg II, 2-segmented; all other branches 3-segmented. All leg I exopod segments have external spine. Terminal exopod spine with fine, widely spaced teeth. External exopod spines thick, long, bordered with hairs. Posterior surface leg II to leg IV endopods with spinules (except B. similis and B. pacificus). Males more slender with comparatively longer abdomen. Leg I first exopod segment often with reduced or absent external spine. Leg V styliform and uniramous with 3 to 5 segments on right, 5-segmented on left; or biramous with rudimentary endopods one of which is sometimes 2-segmented. ACKNOWLEDGMENTS I would like to thank the following people for making available various specimens necessary for this study: Dr A. De Decker of Division of Sea Fisheries, South Africa, for Aetideopsis carinata; Dr J. Jillett of Portobello Marine Biological Station, New Zealand, for Aetideopsis tumorosa from that region; Dr Nils Knaben of Zoologisk Museum, Oslo, Norway, for Bradyidius similis; Dr J. B. L. Matthews of Biologisk Stasjon, Blomsterdalen, Norway, for Aetideopsis armata. REFERENCES BOECK, A. 1872: Nye slaegter og arter af saltvandscopepoder. Fork. VidenskSelsk. Krist. XIV: 35-60. BRADFORD, J. M. (in press) : Studies on New Zealand plankton 1. Pelagic Copepoda from central New Zealand with a key to pelagic genera. Bull. N.Z. Dep. scient. ind. Res. BRODSKY, K. A. 1950: (Calanoida of polar and far eastern seas of U.S.S.R.) Opred. Faune SSSR 35: 442 pp. 1955: (On the copepod (Calanoida) fauna of the Kuril-Kamchatka Trench.) Trudy Inst. Okeanol. 12: 184-209. ESTERLY, C. O. 1911: Third report on the copepods of the San Diego region. Univ. Calif. Publs Zool. 6 (14): 313-53. FARRAN, G. P. 1926: Biscayan plankton collected during a cruise of HMS Research, 1900. Part 14. The Copepoda. J. Linn. Soc. 36: 219-310. FLEMINGER, A. 1957: New calanoid copepods of the families Aetideidae, Euchaetidae and Stephidae from the Gulf of Mexico. Fishery Bull. Fish Wildl. Serv. U.S. 117: 353-63. GIESBRECHT, W. 1897: Notizen zur Systematik der Copepoden. Zool. Anz 20: 253-54. GRICE, G. D. and HULSEMANN, K. 1967: Bathypelagic calanoid copepods of the western Indian Ocean. Proc. U.S. natn. Mus. 122 (3583): 67 pp. MATTHEWS, J. B. L. 1964: On the biology of some bottom-living copepods (Aetideidae and Phaennidae) from western Norway. Sarsia 16: 1-46. SARS, G. O. 1903: "An Account of the Crustacea of Norway", 4, Bergen, 171 pp.

1969] BRADFORD NEW SPECIES OF Aetideopsis 97 TANAKA, O. 1957: The pelagic copepods of the Izu Region, Middle Japan. Systematic account 111. Family Aetideidae (part 1) Pubh Seto mar. biol. Lab. 6 (1): 31-68. UNTERÜBERBACHER, H. K. 1964: The pilchard of South West Africa (Sardinops ocellata). Zooplankton studies in the plankton off Walvis Bay with special reference to the Copepoda. Investl Rep. mar. Res. Lab. S.W. Afr. 11: 42 pp., 36 pls. VERVOORT, W. 1949: Some new and rare Copepoda Calanoida from east Indian seas. Zool. Verh., Leiden, 5: 53 pp. 1952a: Copepoda: Sub-order Calanoida: Family Aetideidae: genus Aetideopsis. Fich. Ident. Zooplancton, Sheet no. 42: 4 pp. 1952b: Copepoda: Sub-order Calanoida: Family Aetideidae: genera Chiridius, Pseudaetideus, Chiridiella. Ibid. Sheet no. 44: 4 pp. 1952c: Copepoda: Sub-order Calanoida: Family Aetideidae: genera Bradyidius, Bradyetes, Bryaxis. Ibid. Sheet no. 43: 4 pp. 1957: Copepods from Antarctic and Sub-antarctic plankton samples. Rep. B.A.N.Z. antarct. Res. Exped. 3 (3): 1-160. 1963: Pelagic Copepoda Part 1 Atlantide Rep. 7: 75-194. WILSON, C. B. 1950: Copepods gathered by the United States Fisheries Steamer Albatross from 1887 to 1909, chiefly in the Pacific Ocean. Bull. U.S. natn. Mus. 14 (4) (= 100): i-ix, 141-441, 35 pls. WITH, C. 1915: Copepoda, 1: Calanoida Amphascandria. In: Dan. Ingolf-Exped. 3 (4): 1-260, 8 pls. WOLFENDEN, R. N. 1904: Notes on the copepoda of the North Atlantic Sea and Faröe Channel. J. mar. biol. Assn U.K., n.s. 7: 110-46. 1905: Plankton Studies. Copepoda. Part 1. (1905): 1-24, London: Rebman. (Not seen). 1908: Crustacea VIII Copepoda. In: Natn. Antarct. Exped., 1901-1904. 4: 46 pp. 7 pls. 1911: Die marinen copepoden der Deutsch Südpolar Expedition 1901-03, 11. Die pelagishen Copepoden der Westwinddrift und des Südlich Eismeres. Dt. Südpol.-Exped. 12 (= Zool. 4): 181-380. Sig.-7