Diversity and zoogeography of Antarctic deep-sea Munnopsidae (Crustacea, Isopoda, Asellota)

ARTICLE IN PRESS

Deep-Sea Research II 54 (2007) 1790–1805 www.elsevier.com/locate/dsr2

Diversity and zoogeography of Antarctic deep-sea Munnopsidae (Crustacea, Isopoda, Asellota) Marina Malyutinaa,, Angelika Brandtb a

A.V. Zhirmunsky Institute of Marine Biology, FEB RAS, Palchevskogo 17, 690041 Vladivostok, Russia b Biozentrum Grindel and Zoological Museum, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany Accepted 5 July 2007 Available online 6 August 2007

Abstract The family Munnopsidae was the most abundant and diverse among 22 isopod families collected by the ANDEEP deepsea expeditions in 2002 and 2005 in the Atlantic sector of the Southern Ocean. A total of 219 species from 31 genera and eight subfamilies were analysed. Only 20% species were known to science, and 11% of these were reported outside the ANDEEP area mainly from other parts of the SO or the South Atlantic deep sea. One hundred and five species (50%) were rare, occurring at only 1 or 2 stations. Seventy-two percent of all munnopsid specimens belong to the most numerous 25 species with a total abundance of more than 75 specimens; 5 of these species (40% of all specimens) belong to the main genera of the world munnopsid fauna, Eurycope, Disconectes, Betamorpha, and Ilyarachna. About half of all munnopsid specimens and 34% of all species belong to the subfamily Eurycopinae, which is followed in occurrence by the Lipomerinae (19%). Munnopsinae is the poorest represented subfamily (1.5%). The composition of the subfamilies for the munnopsid fauna of the ANDEEP area differs from that of northern faunas. Lipomerinae show a lower percentage (7%) in the North Atlantic and are absent in the Arctic and in the North Pacific. This subfamily is considered as young and having a centre of origin and diversification in the Southern Ocean. The analyses of the taxonomic diversity and the distribution of Antarctic munnopsids and the distribution of the world fauna of all genera of the family revealed that species richness and diversity of the genera are highest in the ANDEEP area. The investigated fauna is characterised also by high percentage of endemic species, the highest richness and diversity of the main munnopsid genera and subfamily Lipomerinae. This supports the hypothesis that the Atlantic sector of SO deep sea may be considered as the main contemporary centre of diversification of the Munnopsidae. It might serve as a diversity pump of species of the Munnopsidae to more northern Atlantic areas via the deep water originating in the Weddell Sea. r 2007 Elsevier Ltd. All rights reserved. Keywords: Crustacea; Isopoda; Munnopsidae; Biodiversity; Species richness; Southern Ocean

1. Introduction The three recent deep-sea expeditions of ANDEEP project; ANDEEP I and II (2002) and ANDEEP III Corresponding author.

E-mail address: [email protected] (M. Malyutina). 0967-0645/$ - see front matter r 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.dsr2.2007.07.017

(2005) in the Atlantic sector of the South Ocean (SO), yielded a rich collection of Isopoda, the most abundant and diverse group of which was the Munnopsidae. The Munnopsidae Lilljeborg, 1864 is the largest family of the natatory deep-sea janiroidean Asellota. Munnopsids are an important fraction in any deep-sea benthic communities in the world ocean,

ARTICLE IN PRESS M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805

especially at high latitudes (Hessler et al., 1979; Hessler and Wilson, 1983; Wilson, 1989; Brandt, 1991, 2004; Svavarsson, 1987, 1997; Kussakin, 2003; Raupach et al., 2004). This cosmopolitic family includes nine subfamilies, about 40 genera, and about 400 species. The high species diversity, impressive variety of body forms, and life styles of munnopsids evince a great evolutionary radiation. New finds and intensive investigations of four large genera, Eurycope, Storthyngura, Ilyarachna, and Echinozone, have led to a systematic revision of the munnopsid families. Five new genera, Disconectes, Tytthocope, Belonectes, Baeonectes and Dubinectes were separated from the genus Eurycope (Wilson, 1982a, b, 1983a, b; Wilson and Hessler, 1980, 1981; Malyutina and Brandt, 2006). The former genus Storthyngura was divided into six genera with erecting five new: Microprotus, Storthyngurella, Sursumura, Rectisura, Vanhoeffenura (Wilson et al., 1989; Malyutina, 1999, 2003). For some former Ilyarachna species three new genera, Betamorpha, Amuletta, and Hapsidohedra were described (Hessler and Thistle, 1975; Wilson and Thistle, 1985; Wilson, 1989). Recent investigations (Merrin, 2004, 2006; Merrin et al., in press) restored two genera Notopais and Bathybadistes formerly being synonymised with Echinozone. These taxonomic reconstructions have led to a much more restricted distribution of each of these newly separated genera. In spite of the numerous publications, including Wa¨gele (1989), the phylogenetic system of the Munnopsidae is still not well understood. Wilson (1989) tried to elucidate some systematic problems of the munnopsids sensu lato. He analysed some characters of most of the munnopsid genera and proposed a revised classification. He placed all munnopsid families (Munnopsidae, Acanthocopidae, Bathyopsuridae, Eurycopidae, Ilyarachnidae, Lipomeridae, and Syneurycopidae), reducing these to subfamily status, into one large family Munnopsidae, as originally proposed by Sars (1899). Before, the composition of the large family Eurycopidae was reconsidered by Wolff (1962), who enclosed the genera Eurycope, Storthyngura, Lipomera, Munneurycope, and Munnopsurus into it. However, Wilson left in the Eurycopinae only Eurycope from Wolff’s genera besides the established four new genera. He revised one of the most difficult munnopsids: a problematic group of ‘‘ilyarachnidlike eurycopids’’. Wilson described four new genera, Coperonus, Hapsidohedra, Lionectes and Mimoco-

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pelates, and two new subgenera for Lipomera and placed these into the newly constituted subfamily Lipomerinae. For some genera, which remained incertae sedis according to Wilson, Kussakin (2003) erected the subfamilies Betamorphinae and Storthyngurinae. A large heterogeneous genus Munneurycope, as well as Munnopsurus and Munnicope are still incertae sedis and likely might be combined into one additional subfamily. After the intensive sampling in Atlantic sector of the SO during the expeditions of the ANDEEP project, we got a rich collection of Munnopsidae with many new species. Some species with an unclear intermediate position between Tytthocope (Eurycopinae) and Munneurycope, Mimocopelates (Lipomerinae) and Tytthocope, Lionectes and Hapsidohedra (both Lipomerinae) have been found and are planned to be described and analysed in more detail in future. The findings of these species which cannot be easily placed into the existing genera and some other difficult species with unclear relationships within the Munnopsidae demand careful study. Detailed morphological and genetic comparisons of the species will be required. Such comparisons are difficult because we still deal with sketchy data on morphology, biology and distribution of the species from other regions. Most descriptions of the species are incomplete and not very informative. Taxonomic work on the collected munnopsids is therefore still ongoing. Twelve new species of Storthyngurinae, Acanthocopinae and Eurycopinae have already been described from the ANDEEP collections and 10 known species were redescribed (Brandt and Malyutina, 2002; Malyutina and Brandt, 2004a–d; Merrin et al., in press). Two new genera, Dubinectes and Gurjanopsis were established and the subfamily Eurycopinae was revaluated (Malyutina and Brandt, 2006, 2007). Phylogeographical analyses are important and may indicate the potential origin and relationships of the taxa, as well as the degree of evolutionary advancement. We therefore placed an emphasis on the analyses of the distribution of the genera of the Munnopsidae sampled during the ANDEEP expeditions and collected all data on the distribution of all munnopsid genera in the world oceans. On a basis of the present knowledge, we tried to estimate potential faunal migrations and exchanges of the Munnopsidae and the potential role of the investigated region as a recent centre of diversification of the family.

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M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805

2. Material and methods During the expeditions ANDEEP I and II (2002) and ANDEEP III (2005) samples with the epibenthic sledge (EBS) (Brenke, 2005; Brandt and Barthel, 1995) were taken at 40 stations mainly in the Atlantic sector of the Southern Ocean (see Table 1 and station map in the introduction). The Drake Passage along the Shackleton Fracture Zone was sampled, the area north off Elephant Island and west of the South Shetland Islands, the Bellingshausen Sea with two stations, a transect of four stations in the Powell Basin, a transect across the north-western Weddell Sea, a transect at the South Sandwich Islands, two stations in the Cape Basin, one south of Maud Rise and a transect west off Kapp Norwegia down the continental slope to abyssal depths of the Weddell Basin. The sledge operation procedure is described in Brandt et al. (2007) and Brenke (2005). On deck, the complete samples were transferred into pre-cooled 96% ethanol and kept at least for 48 h in 20 1C for later DNA extraction. Specimens were partly sorted on board or later in the laboratory in the Zoological Museum of the University of Hamburg. All unknown species were provisionally named or numbered. 3. Results and discussion The combined list of the identified species of Munnopsidae collected by the ANDEEP I–III expeditions include 208 species from 31 genera and eight subfamilies. Eleven species previously recorded for the region were not represented in the samples, but were included in the list for the analyses of biodiversity and biogeography. It is still possible that future careful taxonomic comparisons of the collected species of both expeditions may shorten the list. However, many species may prove to be a complex of sibling species as it was already shown for Betamorpha fusiformis (Raupach et al., 2007). Therefore, an increase of the species number of Munnopsidae from this region is more likely than a decrease. One hundred and seventy-three species were unknown and most likely are new to science. A total of 45 species among 219 (20%) were known to science and only 24 (11%) of these were reported from the other parts of the SO or the Southern Atlantic deep sea (Table 1). Therefore, to our present knowledge, 80% of the SO deep-sea

Table 1 List of species known for the investigated area (species which were not sampled during ANDEEP expeditions marked with ) SEA SWA TA NA IndSO EP Acanthocope annulata Acanthocope galatheae Bellibos (Bemerria) monicae Bellibos multispina Betamorpha africana Betamorpha fusiformis Betamorpha characta Coperonus nordenstami Coperonus pinguis Coperonus mirabilis Coperonus pulcher Coperonus gracilis Coperonus vanhoeffeni Disconectes colemani Disconectes vanhoeffeni Dubinectes acutitelson Dubinectes nodosus Ilyrachna nordenstami Ilyarachna antarctica Ilyarachna bicornis Ilyarachna triangular Lionectes humicephalatus Lipomera (Paralipomera) knorrae Munnopsis australis Munneurycope crassa Munnopsurus australis Notopais magnifica Notopais spinosa Rectisura sepigia Storthyngura kussakini Storthyngura elegans +Storthyngura phyllosoma Storthyngurella menziesi Storthyngurella triplispinosa Storthyngurella hirsuta Sursumura spinossisima Sursumura robustisssima Sursumura argentica Sursumura praegrandis Sursumura falcata Syneurycope parallela Syneurycope heezeni Vanhoeffenella scotia Vanhoeffenura birsteini Vanhoeffenura eltaniae



+

+

+ +

+ + +

+

+

+

+

+ + +

+

+

+ + + + + +

+ + + +

+ +

+

+

+ +

+ +

+

SEA, south-eastern Atlantic; SWA, south-west Atlantic; TA, tropical Atlantic; NA, North Atlantic; IndSO, Indian sector of the Southern Ocean; EP, East Pacific.

Munnopsidae are unknown, and 89% considered as putative endemics. It is not unlikely that the high percentage will be reduced when the isopod faunas of the adjacent deep-sea basins are investigated more thoroughly. Until now, the information on Munnopsidae of the south-eastern and south-

ARTICLE IN PRESS M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805

western Atlantic, the Indian and the Pacific sectors of the SO is still scarce. Nevertheless, preliminary results of DIVA (diversity of the abyssal Atlantic Ocean) expeditions illustrated that the munnopsid fauna becomes poorer northwards. Only 14 species are known to be common in the South African basins, 10 species are common in the Argentine basin, 7 in the Indian sector of SO and 4 in the North Atlantic.

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Some undescribed species are morphologically very similar to species from the North Atlantic, the Arctic or even to the North Pacific. These species were provisionally named to document the potential sibling species in the northern deep sea: Paramunnopsis sp. ‘‘justi’’, Mimocopelates sp.1 ‘‘longipes’’, Munneurycope ‘‘nodifrons’’, E. sp. ‘‘dahli’’, E. sp. ‘‘longiflagrata’’, ‘‘E. complanata sp.1’’ and ‘‘E. complanata sp.5’’. These species are especially

Table 2 Composition and numbers of genera ((G)-bold), species (S) and specimens (#) on each station EBS stations

Depth (m)

Midpoint latit1

Midpoint long1

Composition of genera with number of species for each genus

S

G

#

41-3 42-2 43-8 46-7 99-4 105-7 114-4 129-2 131-3 132-2 133-3 134-3 135-4 136-4 137-4 138-6 139-6 140-8 141-10 142-6 143-1

2370 3689 3962 3894 5191 2308 2921 3640 3053 2086 1121 4069 4678 4747 4976 4542 3950 2970 2312 6348 774

59122S 59140S 60127S 60138S 61106S 61124S 61143S 59152S 65120S 65118S 65120S 65119S 65159S 64101S 63145S 62158S 58114S 58116S 58125S 58150S 58144S

60104W 57135W 56105W 53157W 59117W 58151W 60144W 59158W 51131W 53122W 54114W 48103W 43102W 39106W 38148W 27154W 24121W 24154W 24100W 23157W 25110W

(B-5/D-2/E-3/I-4/Sr-1/Sl-1/Bl-1/Sy-1/Me-5/Mp-1) (A-2/B-2/D-3/E-8/T-1/I-7/C -3/H-2/Sl-1/V-2/Sy-1/Me-3/Mp-1) (B-3/D-1/E-8/Ba-1/I-3/C-2/Sl-1/V-1/Me-2/Mp-1) (B-1/D-3/E-4/T-1/N-1/I-4/C-6/Ln-1/Mi-2/Sr-2/Sl-1/Me-2/Mp-1/Mu-2/P-1) (I-1/Sl-1/Mu-1) (E-2) (A-1/B-2/D-5/E-6/N-2/I-6/C-1/Ln-1/Mi-3/Sl-1/V-1/Bl-1/Me-6/Mp-3/Mu-1) (B-1/D-1/E-3/As-1/I-1/Sr-1/Sl-1/Me-2/Mp-1) (A-1/Du-3/E-7/I-3/C-1/H-1/Lp-1/Mi-2/Sl-1/R-1/V-1/Sy-1/Me-2/Mp-2/Mu-1) (Du-1/E-4/I-1/Mi-1/R-1/V-1/Me-3/Mp-2) (B-1/D-3/E-6/T-1/Bn-2/N-2/I-3/C-3/Li-1/Mi-1/Sr-1/Me-1/Mp-2) (B-1/Du-1/E-3/I-1/H-1/Mi-1/Mp-1/P-1) (A-1/B-2/Du-1/E-3/As-2/I-1/Me-1/Mp-1/P-1) (A-1/Du-1/E-3/T-1/As-1/N-1/I-1/Su-1/Sy-1/Me-1/P-1) (B-2/Du-1/E-4/I-2/H-1//Mi-1/Mp-1) (B-1/D-1/Du-1/E-4/I-3/Mi-2/Sl-1/Bl-1/Mp-1) (B-1/E-2/As-1/I-1/Sl-1/Me-2) (B-1/D-3/E-5/I-3/Mi-1/Sl-1/Bl-1/Me-4/Mp-3) (D-6/E-3/T-1/I-3/C-6/Ln-2/Lp-2/Mi-2/R-1/Sl-1/Sr-1/Me-5/Mp-4/Mu-1) No Munnopsidae sampled (B-1/E-2/N-1/I-1/Sl-1/Me-1)

24 36 23 34 3 2 40 12 28 14 28 10 13 13 12 15 8 22 38 0 7

10 13 10 15 3 1 15 9 15 8 13 8 9 11 7 9 6 9 14 0 6

115 402 165 478 5 3 245 35 570 40 365 32 406 52 39 57 30 60 268 0 30

16-10 21-7 59-5 74-6 78-9 80-9

4720 4577 4655 1032 2149 3100

41107S 47139S 67130S 71118S 71109S 70139S

09155E 04115E 00100W 13158W 14100W 14143W

14 6 8 31 27 57

8 4 8 15 14 19

22 16 9 361 201 334

81-8 88-8 94-14 102-3 110-8 121-11 133-2 142-5 150-6 151-7 152-6 153-7 154-9

4382 4931 4891 4801 4695 2659 1584 3405 1984 1183 1998 2096 3803

70132S 68103S 66138S 65134S 64159S 63138S 62146S 62111S 61149S 61145S 62120S 63119S 62132S

14134W 20130W 27110W 36132W 43102W 50137W 53103W 49128W 47128W 47108W 57153W 64137W 64139W

(B-2/D-1/E-6/T-1/I-1/H-1/Bl-1/Mp-1) (B-1/D-1/E-3/B-1) (A-1/B-1/Du-1//E-1/Bt-1/I-1/Sy-1/G-1) (B-1/D-2/E-7/T-2/N-3/I-2/C-1/H-1/Ln-3/Mi-2/Sr-1/Su-1/Bel-1/Me-3/Mp-2) (A-1/B-2/D-1/E-7/T-1/B-1/Bt-2/I-3/C-1/Ln-1/Mi-3/Bel-2/Me-1/Mp-1) (B-1/D-6/Du-1/E-11/T-3/B-1/Bt-1/I-3/C-4/H-2/Ln-1/Lp-5/Mi-3/Sr-1/Sl-1/Su-1/ Sy-3/Me-4/Mp-5) (D-2/E-4/T-1/Bl-1/I-1/C-6/Lp-1/Sr-1/Sl-2//Me-2) (A-2/B-3/Du-2/E-7/I-2/Mi-1/Me-4/Mp-1) (A-1/B-2/D-1/Du-2/E-3/As-1/I-1/Me-3/Mp-1) (B-2/D-1/Du-1/E-2/As-1/H-1/Sl-1/Bl-1/Me-6) (A-1/B-2/Du-2/E-7/As-1/I-1/Ln-1/Sy-1/Me-3) (B-2/D-1/E-8/T-1/Bt-1/N-1/I-2/Ln-1/Mi-2/Sl-1/Me-4) (D-5/E-5/T-3/N-3/I-1/C-2/Ln-2/Sr-2/Su-1/Bl-1/Me-2/Mp-1) (B-1/D-3/E-11/T-1/I-1/C-1/Mi-1/Sl-1/G-1/Mp-3) (B-1/D-4/E-6/N-2/H-1/Ln-1/Mi-5/Sr-1/Su-1/Me-3/Mu-1) (I-1/C-1/H-1/Ln-1/Mi-2/Sr-1/Mp-1) (I-1/Me-1) (B-1/D-1/E-6/I-2/C-1/Ln-3/Mi-1/Sy-1/Me-2/Mp-1/Mu-1) (B-2/E-3/T-1/I-1/H-1/Mi-1/Me-2/Mu-1)

15 22 14 16 19 25 28 24 26 14 2 20 12

10 8 9 9 9 11 12 10 11 9 2 11 8

107 105 36 34 395 174 967 59 289 39 5 108 17

Abbrerations: A, Acanthocope; B, Betamorpha; D, Disconectes; Du, Dubinectes; E, Eurycope; Bn, Belonectes; T, Tytthocope; As, Aspidarachna; I, Ilyarachna; Bt, Bathybadistes; N, Notopais; C, Coperonus; H, Hapsidohedra; Ln, Lionectes; Lp, Lipomera; Mi, Mimocopelates; Sr, Storthyngura; Sl, Storthyngurella; Su, Sursumura; R, Rectisura; V, Vanhoeffenura; Sy, Syneurycope; Bl, Bellibos; Me, Munneurycope; Mp, Munnopsurus; G, Gurjanopsis; M, Munnicope; Mu, Munnopsis; P, Paramunnopsis. a Only those subfamilies are listed of which genera are known.

ARTICLE IN PRESS M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805

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interesting for future detailed taxonomic studies. A few rare, unusual species which were considered to be new genera, were also found. The unusual ‘‘Munneurycope’’, Gurjanopsis australis gen. nov., sp. nov. (Malyutina and Brandt, 2007) is similar to the former Munneurycope incisa Gurjanova, 1946 from the Arctic deep sea. A new species of another potentially new genus, the unusual ‘‘Eurycope’’

n. sp., has the only sibling rare species from northwestern Pacific Trenches, ‘‘Eurycope’’ ovata. 3.1. Distribution of the species (Table 2) Munnopsids were represented at all stations except for the deepest 142-6 (6323 m) and were the most abundant and diverse taxon of the Isopoda in

Table 3 Numbers (N) of genera, species and specimens of the munnopsid subfamilies collected in the ANDEEP area Taxa

Genera per subfamily

Total species

Eurycopinae

5

73

Eurycope Disconectes Tytthocope Dubinectes Belonectes Betamorphinae

1

38 20 6 4 5 9

Lipomerinae

5

40

Coperonus Mimocopelates Lionectes Hapsidohedra Lipomera Lipomera (P) Lipomera (T)

Species occurring at more than 5 stations

Species occurring at 2–4 stations

Species occurring at 1 station (as single specimens in brackets)

Total N of specimens

3080 14 6 2 1 0 2

14 6 3 1 0 2

10 (4) 8 (3) 1 (1) 2 (1) 5 (3) 5 (3)

1519 1302 138 88 11 1073 975

13 10 7 5 3 1 1

1 4 2 3 0 0 0

4 3 3 1 0 1 1

8 3 2 1 3 0 0

(2) (3) (2) (1) (2)

262 307 202 185 4 6 25

27 16 6 3 2

6 1 1 1

3 4 1 1

7 (5) 1 (0) 1 (1) 0

699 494 34 7 20

21 7 5 4 3 2

2 1 1 1 1

2 3 1 1 1

3 1 2 1 0

189 26 23 83 36 17

6 3 3

2 1

1 2

0 0

Ilyarachninae Ilyarachna Notopais Bathybadistes Aspidarachna

4

Stopthyngurinae Sursumura Storthyngura Storthyngurella Vanhoeffenura Rectisura

5

Syneurycopinae Bellibos Syneurycope

2

Acanthocopinae Munneurycope Gurjanopsis Munnopsurus Munnicope

1

4 20 1 8 1

1 5 0 4 0

2 7 1 3 0

1 8 (4) 0 1 (1) 1 (1)

60 409 2 87 1

Munnopsinae Munnopsis Paramunnopsis

2

5 3 2

1 0

2 1

0 1(1)

21 17 4

(1) (0) (1) (1)

59 19 40

41-3 42-2 43-8 46-7 99-4 105-7 114-4 129-2 131-3 132-2 133-3 134-3 135-4 136-4 137-4 138-6 139-6 140-8 141-10 142-6 143-1 2368 3685 3962 2893 5190 2308 2920 3622 3050 2086 1121 4068 4678 4742 4975 4541 3941 2970 2313 6323 755 6 29 47 5

4 23 22

55

20

23 190

67

1

4 33 2 29

1 5

10

1

8 19 16 3 3 112

15

26 311

10

18 6

121 1 10

45 4

8 3 1

12 6 4

1 126 14 22

8

2

18 9

12

1

1 7

29

17 29

7

2

18

13

3

3

14

9

5

1 1

19 1 2 1

104

1 1

7 1

9 8 4

2

6

5

3

2

2

8 1 1

2

4

2

131 5

2

21 20

10 129

1

1

3 1

9

45

2 2

18

1

3 6

2 1

14

1

11 11 15

9

2

2

2

1

5

1 10

7 11

1

1

1795

Betamorpha africana 11 Betamorpha fusiformis 45 Disconectes ‘‘vanhoeffeni’’ 7 Disconectes sp. 1 ‘‘antarctica’’ 4 Disconectes sp. 2 Dubinectes nodosus Eurycope ‘‘complanata’’ sp. 1 14 Eurycope ‘‘complanata’’ sp. 5 Eurycope ‘‘glabra’’ Eurycope sp. 2-rugose plt Eurycope sp. 3-‘‘galathea’’ 1 Eurycope sp. 4-narrow plt 1 Eurycope sp. 8-sim dahli Eurycope sp. 2 Tytthocope sp. 3 Notopais magnifica Ilyarachna antarctica 2 Coperonus pinguis Hapsidohedra sp. 2 Lionectes sp. 2 Mimocopelates sp. 1 ‘‘longipes’’ Mimocopelates sp. 2 Storthyngurella triplispinosa 1 Munneurycope ‘‘harrietae or antarctica’’ Munneurycope ‘‘nodifrons’’ 1

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Stations Depth

M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805

Table 4 Occurrence of the 25 most frequent species of Munnopsidae at ANDEEP stations

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Table 4 (continued ) Stations Depth

16-10 21-7 59-5 74-6 78-9 80-9 81-8 88-8 94-14 102-3 110-8 121-11 133-2 142-5 150-6 151-7 152-6 153-7 154-9 4720 4577 4655 1032 2149 3100 4382 4931 4891 4801 4695 2659 1584 3405 1984 1183 1998 2096 3803

Stations Depth

16-10 21-7 59-5 74-6 78-9 80-9 81-8 88-8 94-14 102-3 110-8 121-11 133-2 142-5 150-6 151-7 152-6 153-7 154-9 4720 4577 4655 1032 2149 3100 4382 4931 4891 4801 4695 2659 1584 3405 1984 1183 1998 2096 3803

Betamorpha africana Betamorpha fusiformis Disconectes ‘‘vanhoeffeni’’ Disconectes sp. 1 ‘‘antarctica’’ Disconectes sp. 2 Dubinectes nodosus Eurycope ‘‘complanata’’ sp. 1 Eurycope ‘‘complanata’’ sp. 5 Eurycope ‘‘glabra’’ Eurycope sp. 2-rugose plt Eurycope sp. 3-‘‘galathea’’ Eurycope sp. 4-narrow plt Eurycope sp. 8-sim dahli Eurycope sp. 2 Tytthocope sp. 3 Notopais magnifica Ilyarachna antarctica Coperonus pinguis Hapsidohedra sp. 2 Lionectes sp. 2 Mimocopelates sp. 1 ‘‘longipes’’ Mimocopelates sp. 2 Storthyngurella triplispinosa Munneurycope ‘‘harrietae or antarctica’’ Munneurycope ‘‘nodifrons’’

1 2 1

1 1

1

1

7

3

7 3 14 10 19

27

6

8

6

1 1 4

3

8 24

6

3 6

14 4 19

11 7

2 9

8 5

23 281

6

1

1

25 1

15

25 1

3

1

15

22 1

6

4

1

1

1 3 1

34

495

1

11

15

1

2

2

3 2

59

2

1

5

15 51

3

4 12 1

1 9

9

3

2 1

2

62

2

79 78 15 10

30

2 1

10

139

3

7 13

12 54

52

3

21 10 2 14

4 6 11

3

1 1 1

14

29 25 4 3

7 1 2 9

4

6

5

17

18 51 12

1

2

2

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M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805

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the samples. Analyses of diversity and distribution of all Isopoda from the ANDEEP stations had been published in a few papers (Brandt et al., 2004, 2005, 2007). The abundance of Munnopsidae was highest (967 specimens) in the Powell Basin at station 133-2 (1584 m); species richness was highest (56 species) in 3100 m at station 80-9 off Kapp Norwegia. Stations 105-7 (2308 m), 99-4 (5191 m) and 152-6 (1998 m) showed the lowest abundance (3, 5 and 5 specimens, respectively), and species richness (2, 4 and 2 species, respectively) (Table in the electronic supplement). A total of 105 species of the Munnopsidae (50%) occurred at one or two of the 39 stations, half of these only with a single specimen at a station, but in some samples the ‘‘rare’’ species were very numerous: 58 specimens of Eurycope sp.15 were collected only at st. 133-3, a single find of 24 specimens of Disconectes sp.2a was sampled at st. 133-2. Disconectes sp.7 occurred at two stations: at st. 142— only two specimens, but at st. 141—25, Eurycope ‘‘complanata’’ sp. 5 also occurs at two stations: at st. 133-3 with 4 specimens, but at st. 131 with 112; Hapsidohedra sp.2 is numerous at different st. 42 and st. 131 with 22 and 129 specimens, respectively. These examples document a patchy distribution pattern characteristic for many isopod species (Brandt et al., 2007). Specimens of a new genus of Eurycopinae, Dubinectes, were sampled mainly in the abyssal plain of the Weddell Sea (stations 134, 135, 136, 137 and 88, 94, 102, 110). Interestingly, at these stations the maximal abundance of one of the most abundant species Betamorpha fusiformis (311 specimens at st. 135 and 281 specimens at st. 110), the highest abundance of Acanthocope galatheae, two species of the rare genus Aspidarachna, and Eurycope ‘‘glabra’’, a potentially new genus with South Atlantic distribution was recorded. Judging from the morphology, all these species seem to be more specialised in burrowing into sediment surface than in swimming. Moreover, on these stations there were only very few specimens of the otherwise common and abundant genus Disconectes (the only 3 specimens of one from 20 species collected during the ANDEEP expeditions). Other good swimmers of the Storthyngurinae and of Munnopsurus were also only rarely found in the abyssal Weddell Sea plain, these occurred more frequently on the slope and in the Drake Passage. Mimocopelates ‘‘longipes’’ was sampled at some of the same stations as species of the Eurycope

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complanata complex. These showed for example a high abundance (131 and 112 specimens, respectively) at st. 131 in 3050 m. It is interesting to note that the records of the same pair of the sibling species, collected together: Mimocopelates longipes and a species of the Eurycope complanata complex were mentioned by Wilson (1989, p. 80) for the North Atlantic. All these examples document that the result of even such an intensive deep-sea sampling at 40 stations might depend on the fortuitousness of the sampling, on the patchiness of the occurrence of the species, depending on their ecology. This result is just some parts of the complicated puzzle, what a real distributional and diversity pattern is. What we may speak about with confidence is the most numerous, key species of the fauna, which were recorded alongside with rare species (Table 3). Seventy-two percent of all munnopsid specimens belong to 25 species with a total abundance of more than 75 specimens each (Table 4). In general, these occur frequently in many samples, but some of them, Hapsidohedra sp.2, Eurycope ‘‘complanata’’ sp.5, Notopais magnifica, and all abundant Lipomerinae, were very numerous only on 2, 3 or 4 stations, and others, Eurycope sp.4 or Storthyngurella triplispinosa occur evenly distributed at many stations with low abundance. Some species, e.g. Eurycope sp.3 ‘‘galathea’’, Eurycope sp. ‘‘dahli’’, Munneurycope sp. ‘‘nodifrons’’, Dubinectes nodosus, and Eurycope sp.2 were sampled at many stations, but with a single specimen at a few stations and a high abundance at others stations. Again, this reflects very different the distributional patterns for the different species, depending on their ecology and biology features. The five most important species occurred with a total abundance of more than 300 specimens, constituting 40% of all specimens. These are: Betamorpha fusiformis occurring at 29 stations with 949 specimens (602 specimens at two stations, st. 135 and st. 110); Disconectes sp.2 (535 specimens from nine stations) with 495 specimens at st. 133-2 and with one to a few specimens at other stations; Disconectes ‘‘antarcticus’’ sp.1 was sampled at nine stations (472 specimens); Eurycope complanata sp.1 has an evenly high abundance at 22 stations (340 specimens); and Ilyarachna antarctica occurs at 19 stations with 301 specimens. These species belong to the richest genera of the world munnopsid fauna. Almost all genera include one or few of the most abundant and frequent key species and some really

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rare ones. Likewise, the subfamilies include both the richest and the poorest in species number genera (Table 3). In the largest genus Eurycope, for example, 14 species of 38 occur at more than 5 stations, and 10 species only at 1 station, 4 species of these were represented by a single specimen. On the contrary, each of the 5 species of the genus Belonectes occurs at a single station and is represented by 1, 2 and once by 5 specimens. It is the rarest genus within the most numerous subfamily Eurycopinae. Within the Lipomerinae the most abundant and speciose genera are Coperonus and Mimocopelates. They occur with 13 and 10 species and 262 and 307 specimens, respectively. The poorest genus Lipomera is represented by 5 species with 35 specimens, and the subgenus Lipomera (Lipomera) with 3 species and just 4 specimens. 3.2. Distribution of the subfamilies The Eurycopinae were collected at almost all stations except for st. 99 (5190 m) and st. 152 (1998 m). Betamorphinae were found evenly distributed at 30 stations with a maximal abundance at the abyssal st. 135 (4678 m) and st. 110 (4695 m) in the Weddell Sea. Interestingly, there were no species of Betamorpha sampled at the richest st. 133-2 and at the most diverse st. 80. Lipomerinae were found at 26 stations from 755 to 4975 m. Ilyarachninae were found everywhere between 755 and 5190 m except for in general poor stations 105 and 21. Munneurycope, were found at 30 stations between 755 m and 4975 m; two specimens of the former Munneurycope, Gurjanopsis australis gen. nov. sp. nov. (Malyutina and Brandt, 2007) occur at st. 59 (4655 m) and st. 142 (3405 m) where there were no Munneurycope species recorded. Storthyngurinae occur at 24 stations from 755 m (st. 143) to 5190 m (st. 99). Munnopsurus were collected at 23 stations, they were poorly represented at the deepest stations. Syneurycopinae occur at 18 stations, in general at the deepest stations. Acanthocopinae were collected at 10 stations, generally deeper than 4000 m; however, the shallowest station 78 was 2149 m deep. Munnopsinae were rare in occurrence (st. 46, 135, 150, 153, but also at st. 99) between 1984 and 5190 m, possibly because of their mainly planktonic, actively swimming life-style. Munnicope was found only at st. 133-3 (1121 m). Most of the frequent species are eurybathic. Ilyarachna antarctica was the most eurybathic

species, it was collected from the shallowest st. 143 (755 m) to the deepest st. 99 (5190 m). Betamorpha fusiformis was also collected at most of the stations from 755 to 4975 m, but is known to consist of several cryptic species (see Raupach et al., 2007); Sursumura longicauda was sampled between 755 and 4742 m, the frequent Munneurycope sp.6 between 755 and 4891 m. Numerous specimens of Notopais magnifica were only present in the shallowest samples between 755 and 1584 m. 3.3. Analyses of the taxonomic composition (Table 3; Fig. 1) A total of 3080 of all 6655 munnopsid specimens (46%) belong to the subfamily Eurycopinae; 92% of these are members of the two richest genera, Eurycope and Disconectes. The next most numerous subfamily is Betamorphinae with 1073 specimens (949 of these are Betamorpha fusiformis). Lipomerinae with 975 specimens, Ilyarachninae with 699 specimens, and Munneurycope (411) are the following noticeable groups. Less numerous taxa, Stopthyngurinae (189), Munnopsurus (87), Acanthocopinae (60), Syneurycopinae (59), and the poorest represented subfamily, Munnopsinae with 21 specimens, contribute only 6% of all munnopsids specimens. Most of the species, including half of the known species, are putative endemics and others are distributed mainly in the South Atlantic and the SO. It is therefore interesting to examine the distribution of the genera and to compare the composition of the genera in different regions of world oceans (Tables 5 and 6). The investigated fauna consists of all subfamilies except for the rare epipelagic subfamily Bathyopsurinae (only four species from two genera are known to date). In the Eurycopinae, the only northern Acanthocopinae Storthyngurinae 1% 3% Munnopsurus Syneurycopinae 1% 1% Munneurycope Munnopsinae 6% 0% Ilyarachninae 11% Eurycopinae 46% Lipomerinae 15%

Betamorphynae 16%

Fig. 1. Relative abundance of munnopsid subfamilies in the ANDEEP area.

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Table 5 Comparison of the species richness of genera of the Munnopsidae in some regions Genus/region

ANDEEP area

South Atlantic

North Atlantic

Arctic

North Pacific

East Pacific

Indian SO

Eurycope ‘‘E. ovata’’ Disconectes Tytthocope Belonectes Dubinectes Baeonectes

38 1 22 6 5 4 0

5 0 1 0 1 2 0

13 0 3 2 1 0 1

9 0 1 1 0 0 1

4 1 1 0 0 0 4

2 0 1 2 1 0 0

2 0 4 0 0 0 0

Ilyarachninae Ilyarachna Aspidarachna Notopais Bathybadistes Echinozone Pseudarachna

16 2 5 4 0 0

4 0 2 3 0 0

7 1 0 1 1 1

6 1 0 0 1 0

9 2 0 0 5 0

2 0 0 0 0 0

2 1 2 0 0 1

Lipomerinae Coperonus Mimocopelates Lionectes Hapsidohedra Lipomera Lipomera (P) Lipomera (T)

16 10 7 5 3 1 1

1 1 0 1 0 0 0

0 1 0 0 1 1 1

0 0 0 0 0 0 0

0 0 0 0 0 0 0

0 0 0 0 0 0 0

? 1 1 1 0 0 0

Storthyngurinae Sursumura Storthyngura Storthyngurella Vanhoeffenura Rectisura Microprotus

7 5 4 3 2 0

0 1 2 1 0 0

2 3 0 0 0 0

0 0 0 0 0 0

0 0 0 3 6 4

0 3 1 2 1 0

0 1 1 1 0 0

Betamorphinae Betamorpha Amuletta

9 0

3 0

4 1

0 0

1 0

1 0

0 0

Syneurycopinae Bellibos Syneurycope

3 3

2 2

3 1

0 0

0 1

0 0

0 0

3 2 0 0 1?

1 0 0 0 1

1 1 1 1 0

1 1 0 0 0

1 1 1 1 1

2 0 2 0 3

2 1 1 0 0

4

4

2

0

1

1

1

20 8 1 1

1 2 0 0

2 2 0 0

2 1 0 1

2 2 3 0

2 1 1 0

3 2 0 0

Munnopsinae Munnopsis Paramunnopsis Munnopsoides Pseudomunnopsis Acanthmunnopsis Acanthocopinae Acanthocope incertae sedis: Munneurycope Munnopsurus Munnicope Gurjanopsis

genus Beaonectes (5 species) was not recorded. Dubinectes is endemic for the South Atlantic. From the Ilyarachninae, the rare genus Pseudarachna (one

species from the North Atlantic and one from New Zealand) was not recorded, and neither was the northern common genus Echinozone. However, the

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Table 6 Geographical and vertical distribution of the genera of the Munnopsidae WS

DP

Acanthocope

2893

Betamorpha

1032 4975 1032 4975 1032 4335 1121 4382 1121 4382 2086 4975

3689 4483 2368 3963

Eurycope Disconectes Belonectes Tytthocope Dubinectes

Aspidarachna Notopais Bathybadistes

2313 4975 2313 4975 1032 4742 4745

ScotiaS

SwA

SEA

3760 5024

4047 5585 1559 587–3906 3049 680–5380 1041 3640 6915 3049 15–30

755 755

NAf

Med

Car

NEA

NWA

1169 1224 3616 4030 4430 5267

2456

3465

1121 4742 2893

550–4885 587–1007 453–4690

150–690

365

9–225 8–4895

8–5226

3100 3050

298–444 2313 1183

Rectisura

3053

Storthyngura

182–1019 2894

Vanhoeffenura

2894

Storthyngurella

5225

Sursumura

3167 3318 4823 4925 1997 5943 4529 4609 1997

792

9–225 20–3965

60–961 100–7230 73–6354

225

2915 5495

2702 3521

205

1183 3685 2893 3962 546–5474

46–3970

4690 4720 4942 8400 308–7230

SEP

Ind SO

N Ind

2650

3290

1830 1837

213–1609

385–3839

6960 7000

385–3423

188–7370

195–930

480?

385 1360 4460 5024

2893

SWP

755

188–1505

Lipomera (Paralipomera) 3100 Mimocopelates 2313 4541 Lionectes 1121 4695 Hapsidohedra 3059 4975 Coperonus 139–3338

Microprotus

1495 2815 150–2258 54–5779

225–471

Echinozone Pseudarachna Lipomera Lipomera (Tetracope)

EP

641–4268

1280 4720 4885

755 51–2310 7000 755

NWP

2802 4426

460–2699 2893 3685

Arc

3819 755 59–282 2313 2970 146

3459

50–478 364 260

3253 3347 104–1003 2665 3015 960–1463

1500 1693

516–1358 1487 470–4822 3864

604–1493 385

2707 3819 508–2707 4720

554–1390 1254 4829 1493

213 385 4690 8430

4071 5190

2894

5600 6150 6150 2281

417–3970 1105 5631

752 1300 7216 2016

1372

4660 4885

4260 4313

2788 5160

1260 8045

3429 6860

5140 1646 2456 544 2028

2950 4173 6281 2487 4423 2596 5690

5850 6720

2012 6760 4464 7000 4400 4468

5461 9345 400–3620 570 3423 2300 2925 400 400

2925

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SS

M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805

Taxa/regions

Bellibos Bellibos (Bemeria) Syneurycope Munnopsis Paramunnopsis

1032 2149 4541 2149 3050 4695 4742 4068 4742

2368

2368 3685 2893 5190 2893

4969 2313 1984

4892

2379

4270

2864

5122

1280

158

4–1200

5005 5045 612–3015 1005 4506

364–2702

1927 4925

Pseudomunnopsis

Gurjanopsis

Paropsurus

1121 1032 4931 3100 4678 4655

755 2368 3685

530–

2313 2970

421–1400

4–1469

3405

2702 2370 7000 2750 640–2709 4–1469

8185 8400 80–1019

Pelagial 7800

4400

860 600–3423

1260 3709 3886

5500 7900

4400 5900 3570 4400 1957

WS, Weddell Sea; DP, Drake Passage; SS, South Sandwich Islands; ScotiaS, Scotia Sea; SWA, South-West Atlantic; SEA, South-East Atlantic; Naf, off North Africa; Med, Mediterranean; Car, Caribbean; NEA, North-East Atlantic; NWA, North-West Atlantic; Arc, Arctic; NWP, North-West Pacific; EP, East Pacific; SWP, South-West Pacific; SEP, South East Pacific; IndSO, Indian sector of the Southern Ocean; N Ind, North Indian O.

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364 2702

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Munnopsurus

1510

2012

Munnopsoides

Acanthomunnopsis Munneurycope

2012

1801

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similar southern genus Notopais, which was considered to be a synonym of Echinozone for a long time, was recorded. Betamorphinae is represented only by Betamorpha, the North Atlantic monotypic genus Amuletta was not recorded. From the Munnopsinae, we did not record the northern genera Munnopsoides (5 species), and Pseudomunnopsis (1 species). The North Pacific Microprotus (4 species) is the only being absent in the subfamily Storthyngurinae from the ANDEEP collections. Kussakin (2003) compiled a biogeographic account of 117 munnopsid species in cold and temperate waters of the northern hemisphere north of 401N. We separated three main biogeographic regions: the North Atlantic, the Arctic and the North Pacific. We prepared species lists for each area in order to compare the composition of the subfamilies of each of these regions with the ANDEEP data (Table 5). All of these regions are comparable with regard to the size of the area. The North Atlantic is as well or even better investigated. First of all, the faunas differ strongly in species richness. While 219 species were reported from the ANDEEP area studied in the SO, only 57 species were reported from the North Atlantic, 25 from the Arctic and 50 from the North Pacific until now. In the North Atlantic almost all genera also sampled during ANDEEP were recorded, except for Notopais and Dubinectes, besides the 5 additional genera mentioned above, but the species richness is much lower than in the ANDEEP area. The Eurycopinae is a dominant subfamily in the faunas of both regions with 34% of all species (Fig. 2). The main difference between the ANDEEP fauna from the northern fauna is that the Eurycopinae is followed by the Lipomerinae (19%) in importance. Ilyarachninae consists almost the same percentages of all species (11%) as Storthyngurinae (10%) and Munneurycope (10%); a share of both Betamorphinae and Munnopsurus is 4%; Syneurycopinae 3%, and Acanthocopinae and Munnopsinae only 2%. On the contrary, in the North Atlantic Ilyarachninae is the second richest taxon with 17% of all species, followed by Betamorphinae with 9%. Lipomerinae consist of the same share (7%) as Storthyngurinae, Syneurycopinae, and Munnopsinae. Acanthocopinae, Munneurycope and Munnopsurus constitute 3% of all species. In the Arctic and the North Pacific Lipomerinae were not recorded at all (Table 6). The Arctic fauna is relatively poor. Lipomerinae, Storthyngurinae, Betamorphinae, Syneurycopinae and Acanthocopinae are

Acanthocopinae 2%

ANDEEP species Syneurycopinae 3%

Munnopsinae 2% Eurycopinae 34%

Munnopsurus 5% Storthyngurinae 10% Munneurycope 10% Ilyarachninae 11%

Acanthocopinae 4%

Lipomerinae 19%

North Atlantic Syneurycopinae 7%

Munnopsurus 4%

Betamorphynae 4%

Munnopsinae 7% Eurycopinae 34%

Stopthyngurinae 7% Betamorphynae 9% Munneurycope Ilyarachninae Lipomerinae 7% 4% 17% Arctic Munnopsurus 4%

Munnopsinae 4%

Munneurycope 8%

Ilyarachninae 33%

Eurycopinae 51% North Pacific

Syneurycopinae 2% Acanthocopinae 2%

Munnopsinae 8% Eurycopinae 21%

Munnopsurus 4% Stopthyngurinae .23% Munneurycope 4%

Betamorphynae 2% Ilyarachninae 34%

Fig. 2. Percentage of species richness of subfamilies of the Munnopsidae in different regions.

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not represented. Eurycopinae (51%) and Ilyarachninae (33%) are the main important munnopsids in that area, Munneurycope is the third important taxon (8%), and Munnopsurus and Munnopsinae hold 4% of the species. In the North Pacific, the Ilyarachninae are the most important subfamily with (34%) followed by Storthyngurinae (23%) and Eurycopinae (21%). The Munnopsinae occur with 4 genera (8%); this is more than a share of each of Munneurycope and Munnopsurus (4% for each genus) and Acanthocopinae, Syneurycopinae and Betamorphinae (2% for each). The most speciose genera of each subfamily demonstrate the highest species richness in the fauna in the ANDEEP area in comparison with other regions (Table 5). The main characteristic of this fauna is the high percentage of Lipomerinae and the highest richness of the subfamily in comparison with other biogeographic areas. Lionectes is endemic for the SO with 7 species, Coperonus occurs with 18 species in the Southern Hemisphere; Mimocopelates with 12 species and Lipomera with 7 species were both sampled in the SO and the North Atlantic. Hapsidohedra with 7 species occurs in the Southern Hemisphere and the North Atlantic. The comparatively high species and genus richness and the rather restricted biogeographic ranges of the genera within the ANDEEP Lipomerinae might lead to the assumption that the Lipomerinae is a young munnopsid subfamily that has radiated and has a centre of origin and diversification in the southern Atlantic part of the SO. In the Lipomerinae, a tendency to paedomorphy is developed. The minimizing of body size, shortening of stages of ontogenesis, where adult reproductive specimens retain juvenile features may lead to the acceleration of changes in the generations and rapid evolution. All these biological characteristics seem to be successful strategies for the deep-sea inhabitants. It might give some competitive preference in terms of the expansion in the threedimensional space. The Lipomerinae were recorded along wide depth ranges (Wilson, 1989; Brandt, 1992), like the other speciose genera Eurycope, Disconectes, Betamorpha, Ilyarachna, Munneurycope and Munnopsurus. As it was postulated (Hessler and Thistle, 1975; Hessler et al., 1979; Hessler and Wilson, 1983; Wilson and Hessler, 1987; Wilson, 1998, 1999; Kussakin, 1973, 2003; Brandt, 2004), the Munnopsidae—like most of the deep-sea asellote families— evolved and radiated in the deep sea in situ, before they have emerged onto the continental shelves,

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especially at higher latitudes. The secondary colonisation of shelves might indicate the advancement of this group, its potential for distribution, and the competitive abilities in the struggle for existence on the shelf, where stress in terms of competition for food and space and pressure by predators should be stronger than in the deep sea. As it would be expected, the most eurybathic genera are the most speciose and abundant ones (Table 6). Eurycope occurs from 46 m in the Arctic occurs down to 7230 m in the Kurile-Kamchatka Trench, Disconectes occurs from 15 m in Mediterranean and 54 m in the North Atlantic to 7000 m in the south-western Pacific. Ilyarachna has been sampled from 8 m at high latitudes to 7370 m in the south-western Pacific; Notopais occurs from 385 to 4742 m), Munneurycope from 530 to 8400 m, Munnopsurus from 4 to 4678 m, Betamorpha from 755 to 8400 m, Coperonus from 139 to 3962 m, Lionectes from 59 to 4695 m, and Storthyngura from 182 to 6281 m. As documented, some of the genera are represented by some rare, not numerous species and some the most abundant and frequent key species– generalists. The latter might be adapted to a wide range of special abiotic and biotic factors in the different areas of their occurrence, what might have caused speciation. Families (or subfamilies) show a composition of both the poorest genera, ‘‘outsiders’’ and the most speciose key genera, ‘‘leaders’’. Presence of occurrence in a regional fauna of macrotaxa (family range or higher) of genera–generalists which demonstrate a wide distribution is considered a main criterion of a centre of diversification (Mironov, 2006). The special geographical features of the position of the ANDEEP area between two continents (South America and Antarctica), with the potential to migrate to all oceans; the rich and diverse bottom topology with ridges, trenches, basins, etc.; the complicated current system of the bottom water masses; the richest eutrophical planktonic zone, forming organically rich sediments (Vinogradova et al., 2000) generally agree with the criteria of a centre of diversification (Briggs, 2003). The similar high-latitude position of the North Atlantic deep sea might explain the wealth of species, some of which have obviously undergone a radiation. 4. Conclusions The analyses of the diversity and distribution of munnopsids from the ANDEEP collections, the

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composition of the subfamilies and the genera and distribution of the World fauna of all genera of Munnopsidae revealed that the richness and diversity of the most frequent genera and subfamilies are highest in the ANDEEP area. The investigated fauna includes the high percentage of endemic species, the high abundance and highest species richness, and the speciose genera displaying South Atlantic or Southern Ocean ranges. These facts support the theory that the Atlantic sector of the Southern Ocean deep sea may be considered as the main contemporary centre of diversification and the northwards flow of the Antarctic bottom water might serve as a diversity pump of species of Munnopsidae to more northern Atlantic areas via the deep water originating in the Weddell Sea. Acknowledgements Financial support for the ANDEEP I–III expeditions was provided by the German Science Foundation Br 1121/26, 1-3; 436 RUS 17/91/03; 436 RUS 17/19/04; 436 RUS 17/103/05; 436 RUS 17/58/06. We are grateful to Prof. D. Fu¨tterer, chief scientist on Polarstern cruise ANT XIX/3-4, and Dr. E. Fahrbach, chief scientist on Polarstern cruise ANT XXII/3, and to the captains and crew of R.V. Polarstern, for help on board. We are grateful to anonymous reviewers, whose comments improved the manuscript. This is ANDEEP publication # 78. Appendix A. Supplementary materials Supplementary data associated with this article can be found in the online version at doi:10.1016/ j.dsr2.2007.07.017. References Brandt, A., 1991. Zur Besiedlungsgeschichte des antarktischen Schelfes am Beispiel der Isopoda (Crustacea, Malacostraca). Berichte zur Polarforschung 98, 1–240. Brandt, A., 1992. The genus Coperonus Wilson, 1989 (Crustacea: Isopoda: Asellota: Munnopsidae). Zoological Journal of the Linnean Society 106, 63–95. Brandt, A., 2004. Abundance, diversity, and community patterns of isopods in the Weddell Sea (Crustacea, Isopoda), (EVOLANTAR). Antarctic Science 16 (1), 5–10. Brandt, A., Barthel, D., 1995. An improved supra- and epibenthic sledge for catching Peracarida (Crustacea, Malacostraca). Ophelia 43 (1), 15–23. Brandt, A., Malyutina, M.V., 2002. Storthyngura kussakini sp. nov. from the Southern Ocean. Mitteilungen aus dem

Museum fur Naturkunde Berlin. Zoologische Reihe 78 (1), 97–107. Brandt, A., Bro¨keland, W., Brix, S., Malyutina, M., 2004. Diversity of Southern Ocean deep-sea Isopoda (Crustacea, Malacostraca)—a comparison with shelf data. Deep-Sea Research Part II 51, 1753–1768. Brandt, A., Ellingsen, K.E., Brix, S., Bro¨keland, W., Malyutina, M., 2005. Southern Ocean deep-sea isopod species richness (Crustacea, Malacostraca): influences of depth, latitude and longitude. Polar Biology 28, 284–289. Brandt, A., Brix S., Bro¨keland, W., Choudhury, M., Kaiser, S., Malyutina, M., 2007. Deep-sea isopod biodiversity, zoogeography and endemism in the Atlantic sector of the Southern Ocean—results from the ANDEEP I–III expeditions. DeepSea Research II, this issue [doi:10.1016/j.dsr2.2007.07.015]. Brenke, N., 2005. An epibenthic sledge for operations on marine soft bottom and bedrock. Marine Technology Society Journal 39 (2), 10–19. Briggs, J.C., 2003. Marine centres of origin as evolutionary engines. Journal of Biogeography 30 (1), 1–18. Hessler, R.R., Thistle, D., 1975. On the place of origin of deepsea isopods. Marine Biology 32, 155–165. Hessler, R.R., Wilson, G.D.F., 1983. The origin and biogeography of malacostracan crustaceans in the deep sea. In: Sims, R.W., Price, J.H., Whalley, P.E.S. (Eds.), The Emergence of the Biosphere. Systematic Association vol. 23, pp. 227–254. Hessler, R.R., Wilson, G.D.F., Thistle, D., 1979. The deep-sea isopods: a biogeographic and phylogenetic overview. Sarsia 64 (1–2), 67–75. Kussakin, O.G., 1973. Peculiarities of the geographical and vertical distribution of marine isopods and the problem of deep-sea fauna origin. Marine Biology 23, 19–34. Kussakin, O.G., 2003. Marine and brackish-water Isopoda of the cold and temperate waters of the Northern Hemisphere. III. Suborder Asellota. Part 3. Family Munnopsidae. (Opredeliteli po faune, izdavaemie Zoologicheskim Institutom Rossiyskoy Academii Nauk). Nauka, pp. 1–381. Malyutina, M.V., 1999. Storthyngurella, a new genus of Munnopsidae (Crustacea: Isopoda), with descriptions of three new species from deep-sea basins of the southern hemisphere. Malyutina, M.V., 2003. Revision of Storthyngura Vanho¨ffen, 1914 (Crustacea: Isopoda: Munnopsididae) with descriptions of three new genera and four new species from the deep South Atlantic. Organisms, Diversity and Evolution 3 (Electr. Suppl. 13) 1–101. Malyutina, M.V., Brandt, A., 2004a. Rectisura menziesi sp. nov.—a new deep-sea isopod from the Weddell Sea, Southern Ocean (Storthyngurinae: Munnopsididae: Asellota). Mitteilungen Hamburgisches Zoologisches Museum und Institut 101, 237–247. Malyutina, M.V., Brandt, A., 2004b. Acanthocopinae (Crustacea: Isopoda: Munnopsididae) from the Southern Ocean deep sea with the description of Acanthocope eleganta sp. nov. Zootaxa 550, 1–20. Malyutina, M.V., Brandt, A., 2004c. New records of Storthyngura (Crustacea, Isopoda, Asellota) from theAntarctic deep sea with descriptions of two new species. Mitteilungen aus dem Museum fur Naturkunde Berlin, Zoologische Reihe 80 (1), 3–32. Malyutina, M., Brandt, A., 2004d. Storthyngurinae (Isopoda, Asellota, Munnopsididae) from the Antarctic deep sea with the descriptions of three new species. Beufortia 58 (1), 1–38.

ARTICLE IN PRESS M. Malyutina, A. Brandt / Deep-Sea Research II 54 (2007) 1790–1805 Malyutina, M., Brandt, A., 2006. A revaluation of the Eurycopinae (Crustacea, Isopoda, Munnopsidae) with a description of Dubinectes gen. nov. from the southern Atlantic deep sea. Zootaxa 1272, 1–44. Malyutina, M.V., Brandt, A., 2007. Gurjanopsis ausrtalis gen. nov., sp. nov, a new deep-sea epibenthic munnopsid (Crustacea, Isopoda, Munnopsidae) from the Weddell Sea, Southern Ocean. Deep-Sea Research II, this issue [doi:10.1016/j.dsr2.2007.07.008]. Merrin, K.L., 2004. Review of the deep-water asellote genus Notopais Hodgson, 1910 (Crustacea: Isopoda: Munnopsididae) with description of three new species from the southwestern Pacific. Zootaxa 513, 1–27. Merrin, K.L., 2006. The first record of the crustacean isopod genus Pseudarachna Sars, 1897 (Isopoda: Asellota: Munnopsidae) from the Southern Hemisphere, with description of a new species from New Zealand. Zootaxa 1370, 59–68. Merrin, K.L., Malyutina, M.V., Brandt, A. A revision of the munnopsidid genus Bathybadistes (Isopoda: Asellota: Munnopsididae) with two new species from the Southern Hemisphere. Invertebrate Systematic, in press. Mironov, A.N., 2006. Centres of marine fauna redistribution. Zoologichesky zhurnal 85 (1), 3–17 (in Russian, English summary). Raupach, M.J., Held, C., Wa¨gele, J.-W., 2004. Multiple colonization of the deep sea by the Asellota (Crustacea: Peracarida: Isopoda). Deep-Sea Research II 51, 1787–1795. Raupach, M.J., Malyutina, M.V., Brandt, A., Wa¨gele, J.-W., 2007. Molecular data reveal a highly diverse species flock within the munnopsoid deep-sea isopod Betamorpha fusiformis (Barnard, 1920) (Crustacea: Isopoda: Asellota) in the Southern Ocean. Deep-Sea Research II, this issue [doi:10.1016/j.dsr2.2007.07.009]. Sars, G.O., 1899. Isopoda. In: An account of the Crustacea of Norway, vol. 2. Bergen Museum, Bergen, Norway, pp. 1–270. Svavarsson, J., 1987. Eurycopidae (Isopoda, Asellota) from bathyal and abyssal depths in the Norwegian, Greenland, and North Polar Seas. Sarsia 72 (3–4), 183–196. Svavarsson, J., 1997. Diversity of isopods (Crustacea): new data from the Arctic and Atlantic oceans. Biodiversity and Conservation 6 (11), 1571–1579. Vinogradova, N.G., Zhivago, A.V., Detinova, N.N., 2000. Deepsea trenches and faults of the Southern Ocean: geological structure, bottom fauna and environmental conditions. Moscow, GEOS, 1–106. Wa¨gele, J.-W., 1989. Evolution und phylogenetisches System der Isopoda. Stand der Forschung und neue Erkenntnisse. Zoologica (Stuttgart) 140, 1–262.

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Wilson, G.D.F., 1982a. Two new natatory asellota isopods (Crustacea) from the San Juan Archipelago, Baeonectes improvisus n. gen., n. sp. and Acanthanummopsis milleri n. sp., with a revised description of A. hystrix Schultz. Canadian Journal of Zoology 60 (12), 3332–3343. Wilson, G.D.F., 1982b. Systematics of a species complex in the deep-sea genus Eurycope, with a revision of six previously described species (Crustacea: Isopoda: Eurycopidae). Bulletin of the Scripps Institution of Oceanography 25, 1–64. Wilson, G.D.F., 1983a. Systematics of a species complex in the deep-sea genus Eurycope, with a revision of six previously described species (Crustacea, Isopoda, Eurycopidae). Bulletin of the Scripps Institution of Oceanography 25, 1–64. Wilson, G.D.F., 1983b. An unusual species complex in the genus Eurycope (Crustacea, Isopoda, Asellota) from the deep North Atlantic ocean. Proceedings of the Biological Society of Washington 96 (3), 452–467. Wilson, G.D.F., 1989. A systematic revision of the deep-sea subfamily Lipomerinae of the isopod crustacean family Munnopsidae. Bulletin of the Scripps Institution of Oceanography 27 (i–xiii), 1–138. Wilson, G.D.F., 1998. Historical influences on deep-sea isopod diversity in the Atlantic Ocean. Deep-Sea Research II 45 (1–3), 279–301. Wilson, G.D.F., 1999. Some of the deep-sea fauna is ancient. Crustaceana 72, 1019–1030. Wilson, G.D.F., Hessler, R.R., 1980. Taxonomic characters in the morphology of the genus Eurycope (Crustacea, Isopoda) with a redescription of E. cornuta Sars, 1864. Cahiers de Biologie Marine 21, 241–263. Wilson, G.D.F., Hessler, R.R., 1981. A revision of the genus Eurycope (Isopoda, Asellota) with descriptions of three new genera. Journal of Crustacean Biology 1 (3), 401–423. Wilson, G.D.F., Hessler, R.R., 1987. Speciation in the deep sea. Annual Review of Ecology and Systematics 18, 185–207. Wilson, G.D., Kussakin, O.G., Vasina, G.S., 1989. A revision of the genus Microprotus Richardson with descriptions of two new species, M. acutispinatus and M. lobispinatus (Asellota, Isopoda, Crustacea). Proceedings of the Biological Society of Washington 102 (2), 339–361. Wilson, G.D., Thistle, D., 1985. Amuletta, a new genus for Ilyarachna abyssorum Richardson, 1911 (Isopoda: Asellota: Eurycopidae). Journal of Crustacean Biology 5 (2), 350–360. Wolff, T., 1962. The systematics and biology of bathyal and abyssal Isopoda Asellota. Galathea Report 6, 1–320.