Macroscapha undetermined

Brandão, Simone N., 2010, Macrocyprididae (Ostracoda) from the Southern Ocean: taxonomic revision, macroecological patterns, and biogeographical implications, Zoological Journal of the Linnean Society 159 (3), pp. 567-672 : 668-669

MACROSCAPHA SUBHEMISPHERICA SP. NOV.

( FIGS 59 , 62J–L , 63J–L )

1991 Macroscapha cf. tensa, Hartmann, 1991: 216 . 1991 Macroscapha cf. turbida, Hartmann, 1991:

216.

Etymology: For its subhemispherical valves.

Material: 41 valves (vials with soft parts of respective specimens were lost).

Holotype: 1 RV, 1 LV were contained on a micropalaeontological slide, labelled ‘ K- 34832 a. Macroscapha cf. tensa , 1♀, Antarktis-Stat. II/493 , Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island ; ZMH K-34832 a.

Paratypes: 2 RV, 2 LV were contained on a micropalaeontological slide, labelled ‘ K- 34829 a. Macroscapha cf. tensa , 1♂, 1 L., Antarktis-Stat . II/174 , Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island ; ZMH K-34829 a.

3 RV, 6 LV (plus broken off valves) were contained on a micropalaeontological slide, labelled ‘ K- 34830 a. Macroscapha cf. tensa , 5♀, 1 L., Antarktis Stat . II/444 , Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island ; ZMH K-34830 a. These specimens are illustrated in Figures 62J and 63J .

1 RV (plus broken valves) were contained on a micropalaeontological slide, labelled ‘ K- 34833 a. Macroscapha cf. tensa , 3♀, Antarktis-Stat . II/473 , Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island ; ZMH K-34833 a.

1 LV (plus broken off valves) were contained on a micropalaeontological slide, labelled ‘ K- 34834 a. Macroscapha cf. tensa , 3♀, Antarktis-Stat. II/81 , Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island; ZMH K-34834 a.

2 RV, 2 LV (plus broken off valves) were contained on a micropalaeontological slide, labelled ‘ K- 34835 a. Macroscapha sp. cf. turbida , ♂, ♀, Antarktis-Stat . II/487 , Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island ; ZMH K-34835 a. These specimens are illustrated in Figures 62K–L and 63K–L .

4 RV, 4 LV (plus broken off valves) were contained on a micropalaeontological slide, labelled ‘ K- 34836 a. Macroscapha sp. cf. turbida , 1 ♂, 7♀, subad., Antarktis-Stat . II / 515 p. 30, Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island ; ZMH K-34836 a.

4 RV, 6 LV (plus broken off valves) were contained on a micropalaeontological slide, labelled ‘ K- 34842 a. Macroscapha cf. tensa , 3♀, 2 subad., Antarktis-Stat . II / 482 p. 29, Koll. Rauschert, det. Hartmann /90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island ; ZMH K-34842 .

2 RV (plus broken off valves) were contained on a micropalaeontological slide, labelled ‘K- 34844a. Macroscapha cf. tensa, Antarktis-Stat. II /193, Koll. Rauschert, det.Hartmann/90’. These specimens were studied by Hartmann (1991). Upper littoral of King Georg Island; ZMH K-34845.

Distribution ( Fig. 59 ): Recent. King Georg Island, Scotia Sea, upper littoral.

Valve measurements ( Fig. 59 ): Holotype, A RV L 1.58 mm, H 0.66 mm; LV L 1.56 mm, H 0.63 mm. Paratypes, A RV L 1.52–1.59 mm, H 0.65–0.70 mm; A LV L 1.48–1.57 mm, H 0.61–65 mm; (A-1) RV L 1.31– 1.38 mm, H 0.55–57 mm; (A-1) LV L 1.22–1.34 mm, H 0.51–57 mm.

Diagnosis: Valves small (for the genus) and subhemispherical in lateral view; dorsal margin highly and continuously arched; ventral margin fairly straight; anterior and posterior margins smoothly rounded; posterior and dorsal margins reaching each other at angle of 90° in RV and 70° in LV. In some specimens RV larger than LV, in others LV larger than RV. Zone of concrescence narrow, with straight radial pore canals; except anteroventrally where it is wider with some ramified radial pore canals.

Remarks: Macroscapha subhemispherica sp. nov., which occurs in the upper littoral, is clearly smaller and less sinuous in outline than Mh. turbida , Mh. scotia , and Mh. rehmi ( Figs 37D–G , 38D–G , 62 , 63 ). The latter three species inhabit greater depths (68– 385 m). Most of the described species of Macroscapha (i.e. Mh. cactus sp. nov., Mh. falcis sp. nov., Mh. gyreae , Mh. inaequalis , Mh. inaequata , Mh. marchilensis , Mh. opaca , Mh. solecavai sp. nov., Mh. walterae sp. nov.) are more elongate, less high in relation to length than Mh. subhemispherica . Additionally, Macroscapha atlantica , Macroscapha heroica , Mh. jiangi , and Mh. sinuata present more sinuous outlines than Mh. subhemispherica .

Figures

Figure 1. Localities for samples studied herein. A, localities from the cruise EASIZ II samples, plus localities from specimens re-studied herein (several cruises from the R. V. Polarstern and R. V. Walter Herwig). B, samples from ANDEEP I, II, and III cruises. Arabic numerals are the station numbers as in the cruise reports. For repeated station numbers: WH, samples collected on board of the R. V. Walter Herwig; PS, samples collected on board of the R. V. Polarstern (cruises other than EASIZ II, PS 48 / ANTXV-3); E, samples collected on board of the R. V. Polarstern during the cruise of EASIZ II (PS 48 / ANTXV-3). Some station names are abbreviated: 1nO, ‘1. Station nach O’Higgins’; Fa, ‘Faraday’; zJU, ‘Zwischen Joinville und d’Urville’. For further details see Table 1. The faunistic analyses discussed below were based on the EBS samples marked ‘*’.

Figure 4. Species accumulation curves. Sobs, number of observed species; UGE, analytical species accumulation curve as proposed by Ugland et al. (2003). A, All EBS samples; B, only EBS samples shallower than 2500m; C, only EBS samples deeper than 2500m.

Figure 37. External view of right valves of Macroscapha inaequata Maddocks, 1990, Macroscapha scotia sp. nov., and Macroscapha walterae sp. nov. Macroscapha inaequata Maddocks, 1990: A, adult female (SNB 0752, ZMH K-40821); B, adult male (SNB 0578-DNA 285. ZMH K-41487); H, (SNB 0052); I, (SNB 0053); J, adult female (SNB 0054) (ZMH 40819). Macroscapha scotia sp. nov.: C, paratype A M? (ZMH K-35501); D, holotype adult male (SNB 0739, ZMH K-40820); E, paratype adult male (SNB 0022); F, paratype adult female (SNB 0056); G, paratype adult female (SNB 0741) (ZMH K-40837). Macroscapha walterae sp. nov.: K, holotype adult male (SNB 0745, ZMH K-41484); L, paratype adult male (SNB 0051); M, paratype adult male (SNB 0750); N, paratype adult female (SNB 0048) (ZMH K-40818). Scale bar = 500 Mm.

Figure 38. External view of left valves of Macroscapha inaequata Maddocks, 1990, Macroscapha scotia sp. nov.; and Macroscapha walterae sp. nov. Macroscapha inaequata Maddocks, 1990: A, adult female (SNB 0752, ZMH K-40821); B, adult male (SNB 0578-DNA 285. ZMH K-41487); H, (SNB 0052); I, (SNB 0053); J, adult female (SNB 0054) (ZMH 40819). Macroscapha scotia sp. nov.: C, paratype A (ZMH K-35501); D, holotype adult male (SNB 0739, ZMH K-40820); E, paratype adult male (SNB 0022); F, paratype adult female (SNB 0056); G, paratype adult female (SNB 0741) (ZMH K-40837). Macroscapha walterae sp. nov.: K, holotype adult male (SNB 0745, ZMH K-41484); L, paratype adult male (SNB 0051); M, paratype adult male (SNB 0750); N, paratype adult female (SNB 0048) (ZMH K-40818). Scale bar = 500 Mm.

Figure 59. Geographical distribution and height ¥ length scatter plot of valves of Macroscapha turbida informal group. Previous records of Mh. turbida from the northern Scotia Sea and from the Pacific Sector of the Southern Ocean are herein considered dubious because they were based on a much wider species morphological concept, which includes at least the three new species described herein – Macroscapha rehmi, Macroscapha scotia, and Macroscapha subhemispherica. Mh. subhemis. – Mh. subhemispherica sp. nov.; Mh. spp. Mad. – dubious records of Mh. turbida by Maddocks (1990); Mh. spp. Hart. – dubious records of Mh. turbida by Hartmann (1987, 1989b).

Figure 62. External view of right valves of Macroscapha rehmi sp. nov., Macroscapha subhemispherica sp. nov., Macroscapha turbida (Müller, 1908), and Macroscapha spp. (from the Mh. turbida group). Macroscapha turbida (Müller, 1908): A, paralectotype adult male (SNB 0747, ZMB 13133); B, adult male (SNB 0343-DNA 80); C, adult male (SNB 0352); D, adult male (SNB 0355); E, adult female (SNB 0356) (ZMH K-41476). Macroscapha rehmi sp. nov.: G, holotype adult male (SNB 0744, ZMH K-41482); H, paratype adult male (SNB 0743); I, paratype adult male (SNB 0059) (ZMH K-40836). Macroscapha subhemispherica sp. nov.: J, paratype A (ZMH K-34830); K, L, paratype A (ZMH K-34835). Macroscapha spp.: F, M, adult female? (ZMH K-35502b). Scale bar = 500 Mm.

Figure 63. External view of left valves of Macroscapha rehmi sp. nov., Macroscapha subhemispherica sp. nov., Macroscapha turbida (Müller, 1908), and Macroscapha spp. (from the Mh. turbida group). Macroscapha turbida (Müller, 1908): A, paralectotype adult male (SNB 0747, ZMB 13133); B, adult male (SNB 0343-DNA 80); C, adult male (SNB 0352); D, adult male (SNB 0355); E, adult female (SNB 0356) (ZMH K-41476). Macroscapha rehmi sp. nov.: G, holotype adult male (SNB 0744, ZMH K-41482); H, paratype adult male (SNB 0743); I, paratype adult male (SNB 0059) (ZMH K-40836). Macroscapha subhemispherica sp. nov.: J, paratype A (ZMH K-34830); K, L, paratype A (ZMH K-34835). Macroscapha spp.: F, M, adult female? (ZMH K-35502b). Scale bar = 500 Mm.