Set number: 1660

  • Orthorhabdus martinii VR 19707 1
  • Orthorhabdus martinii VR 19703 2
  • Orthorhabdus martinii VR 19704 3
  • Orthorhabdus martinii VR 19695 4
  • Orthorhabdus martinii VR 19706 5
  • Orthorhabdus martinii VR 19702 6
  • Orthorhabdus martinii VR 19705 7
  • Orthorhabdus martinii VR 19701 8
  • Orthorhabdus martinii VR 19685 9
  • Orthorhabdus martinii VR 19686 10
  • Orthorhabdus martinii VR 19689 11
  • Orthorhabdus martinii VR 19690 12
  • Orthorhabdus martinii VR 19684 13
  • Orthorhabdus martinii VR 19687 14
  • Orthorhabdus martinii VR 19688 15
  • Orthorhabdus martinii VR 19691 16
  • Orthorhabdus martinii VR 19711 17
  • Orthorhabdus martinii VR 19712 18
  • Orthorhabdus martinii VR 19715 19
  • Orthorhabdus martinii VR 19718 20
  • Orthorhabdus martinii VR 19710 21
  • Orthorhabdus martinii VR 19713 22
  • Orthorhabdus martinii VR 19714 23
  • Orthorhabdus martinii VR 19717 24
  • Orthorhabdus martinii VR 19732 25
  • Orthorhabdus martinii VR 19735 26
  • Orthorhabdus martinii VR 19753 27
  • Orthorhabdus martinii VR 19754 28
  • Orthorhabdus martinii VR 19736 29
  • Orthorhabdus martinii VR 19734 30
  • Orthorhabdus martinii VR 19751 31
  • Orthorhabdus martinii VR 19756 32
  • Orthorhabdus martinii VR 19749 33
  • Orthorhabdus martinii VR 19747 34
  • Orthorhabdus martinii VR 19748 35
  • Orthorhabdus martinii VR 19746 36
  • Orthorhabdus martinii VR 19741 37
  • Orthorhabdus martinii VR 19740 38
  • Orthorhabdus martinii VR 19742 39
  • Orthorhabdus martinii VR 19723 40
  • Orthorhabdus martinii VR 19744 41
  • Orthorhabdus martinii VR 19743 42
  • Orthorhabdus martinii VR 19745 43
  • Orthorhabdus martinii VR 19733 44
  • Orthorhabdus martinii VR 19693 45
  • Orthorhabdus martinii VR 19700 46
  • Orthorhabdus martinii VR 19699 47
  • Orthorhabdus martinii VR 19698 48
  • Orthorhabdus martinii VR 19719 49
  • Orthorhabdus martinii VR 19720 50
  • Orthorhabdus martinii VR 19692 51
  • Orthorhabdus martinii VR 19697 52
  • Orthorhabdus martinii VR 19694 53
  • Orthorhabdus martinii VR 19696 54
  • Orthorhabdus martinii VR 19721 55
    10µm
ODP Leg 154, Hole 926A, Ceará Rise, western equatorial Atlantic.

in mobile mount

Set number: 1663

  • Orthorhabdus serratus VR 16853 1
  • Orthorhabdus serratus VR 16849 2
  • Orthorhabdus serratus VR 16858 3
  • Orthorhabdus serratus VR 16860 4
  • Orthorhabdus serratus VR 16854 5
  • Orthorhabdus serratus VR 16850 6
  • Orthorhabdus serratus VR 16857 7
  • Orthorhabdus serratus VR 16859 8
  • Orthorhabdus serratus VR 16868 9
  • Orthorhabdus serratus VR 16869 10
  • Orthorhabdus serratus VR 16870 11
  • Orthorhabdus serratus VR 16871 12
  • Orthorhabdus serratus VR 16867 13
  • Orthorhabdus serratus VR 16865 14
  • Orthorhabdus serratus VR 16864 15
  • Orthorhabdus serratus VR 16861 16
    10µm
DSDP Leg 25, Site 242, Mozambique Channel (Davie Ridge), Indian Ocean

Set number: 1662

  • Orthorhabdus serratus VR 18045 1
  • Orthorhabdus serratus VR 18044 2
  • Orthorhabdus serratus VR 18048 3
  • Orthorhabdus serratus VR 18052 4
  • Orthorhabdus serratus VR 18046 5
  • Orthorhabdus serratus VR 18043 6
  • Orthorhabdus serratus VR 18047 7
  • Orthorhabdus serratus VR 18053 8
  • Orthorhabdus serratus VR 18060 9
  • Orthorhabdus serratus VR 18061 10
  • Orthorhabdus serratus VR 18062 11
  • Orthorhabdus serratus VR 18064 12
  • Orthorhabdus serratus VR 18059 13
  • Orthorhabdus serratus VR 18058 14
  • Orthorhabdus serratus VR 18056 15
  • Orthorhabdus serratus VR 18055 16
    10µm
IODP Expedition 354, Hole U1451B, Bengal Fan, Indian Ocean

Set number: 1661

  • Orthorhabdus serratus VR 028102 1
  • Orthorhabdus serratus VR 028109 2
  • Orthorhabdus serratus VR 028110 3
  • Orthorhabdus serratus VR 028119 4
  • Orthorhabdus serratus VR 028103 5
  • Orthorhabdus serratus VR 028108 6
  • Orthorhabdus serratus VR 028111 7
  • Orthorhabdus serratus VR 028116 8
  • Orthorhabdus serratus VR 028104 9
  • Orthorhabdus serratus VR 028105 10
  • Orthorhabdus serratus VR 028113 11
  • Orthorhabdus serratus VR 028112 12
  • Orthorhabdus serratus VR 028115 13
  • Orthorhabdus serratus VR 028114 14
  • Orthorhabdus serratus VR 028118 15
  • Orthorhabdus serratus VR 028117 16
  • Orthorhabdus serratus VR 028107 17
  • Orthorhabdus serratus VR 028106 18
    10µm
DSDP Leg 25, Site 242, Mozambique Channel (Davie Ridge), Indian Ocean

Set number: 477

  • Triamutilaferrum martinii 27657 1
  • Orthorhabdus serratus 27656 2
  • Orthorhabdus serratus 27653 3
  • Orthorhabdus serratus 27661 4
  • Orthorhabdus serratus 27658 5
  • Orthorhabdus serratus 27655 6
  • Orthorhabdus serratus 27654 7
  • Orthorhabdus serratus 27659 8
  • Orthorhabdus serratus 27660 9
    10µm
Orthorhabdus serratus, Middle Miocene, DSDP Leg 25, Site 242, Mozambique Channel (Davie Ridge), Indian Ocean
Final Epithet
Orthorhabdus serratus Bramlette & Wilcoxon, 1967
Basionym

Orthorhabdus serratus Bramlette & Wilcoxon, 1967

Remarks

The mobile mount reveals that blades in Orthorhabdus are at equal angles to each other (plate 8, Figures 9-16 in Varol, 2025). The side view displays an inclined (oblique) extinction (Plate 9, Figures 3, 7, 9, 12-13, 16 in Varol, 2025); the extinction angle varies depending on how the “toe” of the hockey stick faces. The extinction angle is about 20° in the side view when the toe is directed to the left (Plate 9, Figures 3, 7 in Varol, 2025). In the plan view, Orthorhabdus appears in constant extinction (with the optic axis vertical to the microscope stage in this orientation, Plate 8 Figs. 1-3, 5-7 in Varol, 2025). Orthorhabdus serratus differs from the other taxa in the family Triquetrorhabdulaceae by having blades truncated at one end and pointed at the other. Orthorhabdus serratus also differs in that it has an inclined optic axis and exhibits length-slow (+) elongation at the side view.

References

Bramlette, M. N. & Wilcoxon, J. A. 1967. Middle Tertiary calcareous nannoplankton of the Cipero section, Trinidad, W.I. Tulane Studies in Geology and Paleontology 5: 93-131.

Gartner, S. 1967a. Calcareous nannofossils from Neogene of Trinidad, Jamaica, and Gulf of Mexico. University of Kansas Paleontological Contributions, Papers 29: 1-7.

Martini, E. 1965. Mid-Tertiary calcareous nannoplankton from Pacific deep-sea cores. Colston Papers 17: 393-411.

Varol, O. 2025a. A practical guide to optical studies of calcareous nannofossils. Grzybowski Foundation Special Publication. 29: 1-222