DOI: 10.5061/dryad.h37n6
title: Data from: The ‘Oxycythereis’ problem: taxonomy and palaeobiogeography of deep-sea ostracod genera Pennyella and Rugocythereis

description: Systematic revision of the globally distributed deep-sea ostracod genera
 Pennyella Neale, 1974 and Rugocythereis Dingle, Lord and Boomer, 1990,
 which have been considered to correspond, at least partially, to nomen
 nudum but widely used genus name ‘Oxycythereis,’ was conducted to reduce
 taxonomic uncertainty of these important components of the Modern and
 fossil deep-sea ostracod community. Approximately 100 specimens from 18
 species were examined, ranging in age from the Cretaceous to the present
 day. Nine new species are described: Pennyella rexi, Pennyella sanfordae,
 Pennyella liowae, Pennyella schellenbergi, Pennyella majorani, Pennyella
 iani, Pennyella ayressi, Rugocythereis melonis and Rugocythereis
 zarikiani. Emended generic concepts of Pennyella and Rugocythereis are
 proposed, and the palaeobiogeographical distributions of these two genera
 are discussed.
description: High-resolution Fig.
 2High-resolution Fig. 2.
 Morphology of Pennyella and Rugocythereis. Based on Pennyella rexi sp.
 nov. (top) and Rugocythereis horrida (bottom). AIL, anterior inner
 lamella; AMF, anterior marginal frill; AMR, anterior marginal rim; AMS,
 anterior marginal sulcus; AMSc, adductor muscle scars; CSP, clavate
 spines; DMS, dorsomedian scar; DS, dorsal scar; FMS, frontal muscle scar;
 HIN, hingement; MHE, median hinge element; PDT, posterodorsal tubercle;
 PIL, posterior inner lamella; PMR, posterior marginal rim; PMS, posterior
 marginal sulcus; PR, primary reticulation; PVS, posteroventral spine;
 SCMS, subcentral muscle scars; SKS, snap-knob structure (‘additional
 closing mechanism’ sensu Mazzini 2005); SP, spines; SR, secondary
 reticulation; VMS, ventromedian scar; VR, ventral ridge; VS, ventral
 scar.yasuhara_fig2.tifHigh-resolution Fig. 5High-resolution Fig. 5. Scanning electron microscopy images of Pennyella rexi sp. nov. A, C, E, G, I, K, M–Q, lateral views; B, D, F, H, J, L, internal views. A–B, paratype USNM 557977; adult LV from ODP 982A, 1/2/47–49, Late Pleistocene. C–D, holotype USNM 557978; adult RV from ODP 982A, 1/2/47–49, Late Pleistocene. E–F, paratype USNM 557979; adult LV from ODP 982A, 1/1/127–129, Late Pleistocene. G–H, paratype USNM 557980; adult RV from ODP 982A, 1/1/127–129, Late Pleistocene. I–J, paratype USNM 557981; adult RV from ODP 982A, 1/3/72–74, Late Pleistocene. K–L, paratype USNM 557982; adult LV from ODP 982A, 1/3/72–74, Late Pleistocene. M, USNM 557983; adult LV from Chain 82-24-4P, 476–478.5 cm, Late Pleistocene. N, USNM 557984; adult RV from Chain 82-24-4P, 476–478.5 cm, Late Pleistocene. O, USNM 557985; adult LV from Chain 82-24-4P, 68–71 cm, Late Pleistocene. P, USNM 557986; adult RV from Chain 82-24-4P, 68–71 cm, Late Pleistocene. Q, USNM 557987; adult LV from DSDP 607, 13/5/90–92, Late Pliocene. Scale bar represents 1 mm.yasuhara_fig5.tifHigh-resolution Fig. 6High-resolution Fig. 6. Scanning electron microscopy images of Pennyella rexi sp. nov. A, C, E, G–K, N–O, Q–U, lateral views; B, D, F, L–M, P, internal views. A–B, USNM 557988; adult RV from DSDP 607, 13/5/90–92, Late Pliocene. C–D, USNM 557989; adult RV from DSDP 607, 13/1/77–79, Late Pliocene. E–F, USNM 557990; adult LV from DSDP 607, 13/1/77–79, Late Pliocene. G, USNM 557991; adult RV from ODP 980C, 2/4/80–82, Late Pleistocene. H, USNM 557992; adult LV from ALB 2566, Recent. I, USNM 557993; adult LV from DSDP 552A, 14/2/50–52, Early Pliocene. J, USNM 557994; adult RV from DSDP 552A, 9/3/77–79, Late Pliocene. K–L, USNM 557995; adult LV from KN 714-15A, 118 cm, Late Pleistocene. M–N, USNM 557996; adult RV from KN 714-15A, 128 cm, Late Pleistocene. O–P, USNM 557997; adult RV from Chain 82-24-4P, 467–470 cm, Late Pleistocene. Q, USNM 557998; adult LV from DSDP 552A, 19/2/50–52, Early Pliocene. R, USNM 557999; adult LV from DSDP 607, 15/7/21, Late Pliocene. S, USNM 558000; adult LV from KN714-15A, 188 cm, Holocene. T, USNM 558001; adult LV from DSDP 552A, 10/2/69–71, Late Pliocene. U, USNM 558002; adult RV from DSDP 552A, 11/1/108–110, Late Pliocene. Scale bar represents 1 mm.Yasuhara_fig6.tifHigh-resolution Fig. 7High-resolution Fig. 7. Scanning electron microscopy images of Pennyella rexi sp. nov. and Pennyella sanfordae sp. nov. A–F, internal features of P. rexi sp. nov. A–B, holotype, adult RV (USNM 557978). A, hingement and B, subcentral muscle scars. C–D, paratype, adult LV (USNM 557977). C, hingement and D, subcentral muscle scars. E–F, paratype, adult RV (USNM 557980). E, hingement and F, subcentral muscle scars. G–J, internal features of P. sanfordae sp. nov. G–H, holotype, adult RV (USNM 558006). G, hingement and H, subcentral muscle scars. I–J, paratype, adult LV (USNM 558003). I, hingement and J, subcentral muscle scars. Scale bars represent 100 µm.Yasuhara_fig7.tifHigh-resolution Fig. 8High-resolution Fig. 8. Scanning electron microscopy images of Pennyella sanfordae sp. nov. and Pennyella liowae sp. nov. A, C, E, G, I–J, L, N, P, R, T–U, lateral views; B, D, F, H, K, M, O, Q, S, internal views. A–Q, P. sanfordae sp. nov. A–B, paratype USNM 558003; adult LV from DSDP 526A, 1/1/60–67, Early Pliocene. C–D, paratype USNM 558004; adult RV from DSDP 526A, 1/1/60–67, Early Pliocene. E–F, paratype USNM 558005; adult LV from DSDP 526A, 1/1/60–67, Early Pliocene. G–H, holotype USNM 558006; adult RV from DSDP 526A, 1/1/60–67, Early Pliocene. I, paratype USNM 558007; adult RV from DSDP 526A, 4/1/120–127, Early Pliocene. J–K, USNM 558008; adult LV from DSDP 526A, 18/1/130–137, Middle Miocene. L–M, USNM 558009; adult RV from DSDP 526A, 18/1/ 130–137, Middle Miocene. N–O, USNM 558010; adult LV from DSDP 526A, 26/1/20–27, Early Miocene. P–Q, USNM 558011; adult RV from DSDP 526A, 26/1/20–27, Early Miocene. R–U, P. liowae sp. nov. R–S, holotype USNM 558012; adult RV from DSDP 18, 6/5/50–56, Late Oligocene. T, paratype USNM 558013; adult LV from DSDP 363, 1/3/53–65, Middle Miocene. U, paratype USNM 558014; adult RV from DSDP 14, 2/3/50–56, Late Oligocene. Scale bar represents 1 mm.Yasuhara_fig8.tifHigh-resolution Fig. 9High-resolution Fig. 9. Scanning electron microscopy images of Pennyella liowae sp. nov. and Pennyella schellenbergi sp. nov. A–B, internal features of P. liowae sp. nov., holotype, adult RV (USNM 558012). A, hingement and B, subcentral muscle scars. C–F, internal features of P. schellenbergi sp. nov. C–D, holotype, adult RV (USNM 558019). C, hingement and D, subcentral muscle scars. E–F, paratype, adult RV (USNM 558017). E, hingement and F, subcentral muscle scars. Scale bars represent 100 µm.Yasuhara_fig9.tifHigh-resolution Fig. 10High-resolution Fig. 10. Scanning electron microscopy images of Pennyella schellenbergi sp. nov., Pennyella majorani sp. nov. and Pennyella iani sp. nov. A, C, E, G–H, J, M–Q, T, lateral views; B, D, F, I, K–L, R–S, internal views. A–I, P. schellenbergi sp. nov. A, USNM 558015; adult LV from DSDP 214, 28/3/50–56, Late Eocene. B–C, USNM 558016; adult RV from DSDP 214, 28/3/50–56, Late Eocene. D–E, paratype USNM 558017; adult RV from DSDP 363, 1/6/47–58, Early Miocene. F, H, holotype USNM 558019; adult RV from DSDP 363, 9/2/47 –57, Late Eocene. G, I, paratype USNM 558018; adult LV from DSDP 363, 10/5/46–57, Middle Eocene. J–M, P. majorani sp. nov. J, holotype USNM 558020; adult LV from DSDP 327A, 13/2/100–105, Campanian–Maastrichtian, Upper Cretaceous. K, paratype USNM 558021; adult RV from DSDP 327A, 13/2/100–105, Campanian–Maastrichtian, Upper Cretaceous. L–M, paratype USNM 558022; adult RV from DSDP 327A, 13/2/100–105, Campanian–Maastrichtian, Upper Cretaceous, N–T, P. iani sp. nov. N, holotype USNM 558023; adult LV from DSDP 44, 1/3/50–56, Early Oligocene. O, paratype USNM 558024; adult RV from DSDP 44, 1/3/50–56, Early Oligocene. P, paratype USNM 558025; adult LV from DSDP 44, 1/3/50–56, Early Oligocene. Q, paratype USNM 558026; adult RV from DSDP 44, 1/3/50–56, Early Oligocene. R, paratype USNM 558027; adult LV from DSDP 44, 5/cc, Middle Eocene. S, paratype USNM 558028; adult RV from DSDP 44, 5/cc, Middle Eocene. T, paratype USNM 558029; adult LV from DSDP 44, 5/cc, Middle Eocene. Scale bars represent 1 mm.Yasuhara_fig10.tifHigh-resolution Fig. 11High-resolution Fig. 11. Scanning electron microscopy images of Pennyella majorani sp. nov., Pennyella iani sp. nov. and Pennyella ayressi sp. nov. A–B, internal features of P. majorani sp. nov., paratype, adult RV (USNM 558021). A, hingement and B, subcentral muscle scars. C–F, internal features of P. iani sp. nov. C–D, paratype, adult LV (USNM 558027). C, hingement and D, subcentral muscle scars. E–F, paratype, adult RV (USNM 558030). E, hingement and F, subcentral muscle scars. G–J, internal features of P. ayressi sp. nov. G–H, holotype, adult LV (USNM 558037). G, hingement and H, subcentral muscle scars. I–J, paratype, adult RV (USNM 558038). I, hingement and J, subcentral muscle scars. Scale bars represent 100 µm.Yasuhara_fig11.tifHigh-resolution Fig. 12High-resolution Fig. 12. Scanning electron microscopy images of Pennyella iani sp. nov., Pennyella sp. 1, Pennyella ayressi sp. nov., Pennyella sp. 2 and Pennyella sp. 3. A, D–I, K, M, O–P, R, lateral views; B–C, J, L, N, Q, S, internal views. A–H, P. iani sp. nov. A–B, paratype USNM 558030; adult RV from DSDP 44, 5/cc, Middle Eocene. C–D, USNM 558031; adult RV from DSDP 44, 5/cc, Middle Eocene. E, USNM 558032; adult LV from DSDP 44, 3/3/50–56, Middle Eocene. F, USNM 558033; adult RV from DSDP 44, 3/3/50–56, Middle Eocene. G, USNM 558034; adult LV from DSDP 44, 3/3/50–56, Middle Eocene. H, USNM 558035; adult RV from DSDP 44, 3/3/50–56, Middle Eocene. I–J, Pennyella sp. 1., USNM 558036; adult RV from DSDP 56.2, 1/3/50–56, Late Miocene. K–O, P. ayressi sp. nov. K–L, holotype USNM 558037; adult LV from DSDP 305, 8/5/54–60, Oligocene. M–N, paratype USNM 558038; adult RV from DSDP 305, 8/5/54–60, Oligocene. O, paratype USNM 558039; adult LV from DSDP 305, 8/5/54–60, Oligocene. P–Q, Pennyella sp. 2, USNM 558040; adult RV from DSDP 305, 16/3/50–56, Cretaceous, late Maastrichtian. R–S, Pennyella sp. 3., USNM 558041; adult RV from DSDP 56.2, 9/2/48–54, Late Oligocene. Scale bar represents 1 mm.Yasuhara_fig12.tifHigh-resolution Fig. 13High-resolution Fig. 13. Internal features of Pennyella species. A–B, Pennyella sp. 1, adult RV (USNM 558036). A, hingement and B, subcentral muscle scars. C–D, Pennyella sp. 2, adult RV (USNM 558040). C, hingement and D, subcentral muscle scars. E, Pennyella sp. 3, adult RV (USNM 558041), hingement. Scale bars represent 100 µm.Yasuhara_fig13.tifHigh-resolution Fig. 14High-resolution Fig. 14. Scanning electron microscopy images of Rugocythereis melonis sp. nov. and Rugocythereis horrida (Whatley and Coles, 1987). A–B, E–G, I, K, M, lateral views; C–D, H, J, L, N, internal views. A–J, R. melonis sp. nov. A, USNM 558042; adult LV from KN25 sta287, coretop, Modern. B, USNM 558043; adult RV from KN25 sta287, coretop, Modern. C, USNM 558044; adult LV from KN25 sta287, coretop, Modern. D, USNM 558045; adult RV from KN25 sta287, coretop, Modern. E, USNM 558046; adult RV from KN25 sta287, coretop, Modern. F, paratype USNM 558047; adult RV from DSDP 357, 20/2/106–120, Late Eocene. G–H, holotype USNM 558048; adult LV from DSDP 357, 20/2/106–120, Late Eocene. I–J, paratype USNM 558049; adult RV from DSDP 357, 20/2/106–120, Late Eocene. K–N, R. horrida (Whatley and Coles, 1987). K–L, USNM 558050; adult RV from DSDP607, 15/5/113–115, Late Pliocene. M–N. USNM 558051; adult LV from DSDP607, 15/5/113–115, Late Pliocene. Scale bar represents 1 mm.Yasuhara_fig14.tifHigh-resolution Fig. 15High-resolution Fig. 15. Scanning electron microscopy images of Rugocythereis horrida (Whatley and Coles, 1987) and Rugocythereis leptodictyota (Ayress, 1995). A–D, F, H–I, K, M, O, R–S, lateral views; E, G, J, L, N, P–Q, internal views. A–N, R. horrida (Whatley and Coles, 1987). A, USNM 558052; adult LV from DSDP 552A, 16/2/130–132, Late Pliocene. B, USNM 558053; adult LV from DSDP 552A, 15/3/38–40, Late Pliocene. C, USNM 558054; adult RV from DSDP 552A, 9/3/58–60, Late Pliocene. D–E, USNM 558055; adult LV from KN714-15A, 393 m, Late Pleistocene. F–G, USNM 558056; adult RV from KN714-15A, 364 m, Late Pleistocene. H, USNM 558057; adult RV from KN714-15A, 30 cm, Holocene. I–J, USNM 558058; adult RV from Chain 82-24-4P, 638–640 cm, Late Pleistocene. K–L, USNM 558059; adult RV from NMC17, coretop, Modern. M–N, USNM 558060; adult RV from DSDP 277, 5/1/50–57, middle–late Oligocene. O–S, R. leptodictyota (Ayress, 1995). O, USNM 558061; adult LV from Ashley Mudstone Formation, outcrop, Late Eocene. P, S, USNM 558062; adult LV from Ashley Mudstone Formation, outcrop, Late Eocene. Q–R, USNM 558063; adult RV from Ashley Mudstone Formation, outcrop, Late Eocene. Scale bars represent 1 mm.Yasuhara_fig15.tifHigh-resolution Fig. 16High-resolution Fig. 16. Internal features of Rugocythereis horrida (Whatley and Coles, 1987). A, adult LV (USNM 558051), hingement. B, adult LV (USNM 558055), subcentral muscle scars. C–E, adult RV (USNM 558059). C, hingement; D, subcentral muscle scars; and E, ventromarginal area showing snap-knob structure. Scale bars represent 100 µm.Yasuhara_fig16.tifHigh-resolution Fig. 17High-resolution Fig. 17. Internal features of Rugocythereis melonis sp. nov. A–B, adult LV (USNM 558044). A, hingement and B, subcentral muscle scars. C–D, adult RV (USNM 558045). C, hingement and D, subcentral muscle scars. E–F, holotype, adult LV (USNM 558048). E, hingement and F, subcentral muscle scars. G–H, paratype, adult RV (USNM 558049). G, hingement and H, subcentral muscle scars. Scale bars represent 100 µm.Yasuhara_fig17.tifHigh-resolution Fig. 18High-resolution Fig. 18. Scanning electron microscopy images of Rugocythereis reticulata Ayress, 1993b, Rugocythereis klaszi (Colin, 1987) and Rugocythereis zarikiani sp. nov. A, C, E, G, I, K, M, O, Q–R, lateral views; B, D, F, H, J, L, N, P, internal views. A–D, R. reticulata Ayress, 1993b. A–B, USNM 558064; adult LV from Hampden Formation, outcrop, Middle Eocene. C–D, USNM 558065; adult RV from Hampden Formation, outcrop, Middle Eocene. E–L, R. klaszi (Colin, 1987). E–F, USNM 558066; adult LV from DSDP 329, 5/6/80–88, Late Miocene. G–H, USNM 558067; adult RV from DSDP 329, 5/6/80–88, Late Miocene. I–J, USNM 558068; adult RV from DSDP 327A, 12/3/50–55, Maastrichtian, Upper Cretaceous. K–L, USNM 558069; adult LV from DSDP 327A, 13/2/100–105, Campanian–Maastrichtian, Upper Cretaceous. M–R, R. zarikiani sp. nov. M–N, paratype USNM 558070; adult LV from DSDP 284, 18/1/130–137, Late Miocene. O, paratype USNM 558071; adult LV from DSDP 279A, 8/1/81–89, Early Miocene. P–Q, holotype USNM 558072; adult LV from DSDP 279A, 8/1/81–89, Early Miocene. R, paratype USNM 558073; adult LV from DSDP 279A, 8/1/81–89, Early Miocene. Scale bars represent 1 mm.Yasuhara_fig18.tifHigh-resolution Fig. 19High-resolution Fig. 19. Internal features of Rugocythereis klaszi (Colin, 1987). A–B, adult LV (USNM 558066). A, hingement and B, subcentral muscle scars. C–D, adult RV (USNM 558067). C, hingement and D, subcentral muscle scars. Scale bars represent 100 µm.Yasuhara_fig19.tifHigh-resolution Fig. 20High-resolution Fig. 20. Scanning electron microscopy images of Rugocythereis leptodictyota (Ayress, 1995). A–C lateral views; D–H internal views. A, paratype, adult LV (OU 40480). B, adult LV from the type locality. C, holotype, adult RV (OU 40478). D–E, adult LV (USNM 558062). D, hingement and E, subcentral muscle scars. F–H, adult RV (USNM 558063). F, hingement; G, subcentral muscle scars; and H, ventromarginal area showing snap-knob structure. Scale bars represent 1 mm for A–C, 100 µm for D–H.Yasuhara_fig20.tifHigh-resolution Fig. 21High-resolution Fig. 21. Internal features of Rugocythereis reticulata Ayress, 1993b and Rugocythereis zarikiani sp. nov. A–E, R. reticulata Ayress, 1993b. A–B, adult LV (USNM 558064). A, hingement and B, subcentral muscle scars. C–E, adult RV (USNM 558065). C, hingement; D, subcentral muscle scars; and E, ventromarginal area showing snap-knob structure. F–G, R. zarikiani sp. nov., holotype, adult LV (USNM 558072). F, hingement and G, subcentral muscle scars. Scale bars represent 100 µm.Yasuhara_fig21.tifAppendix S1Appendix S1. Detailed information of the specimens used for the present study.Appendix_S1_USNM_fin.xls