Nassellaria

Zygocircus productus, from here.

Belongs within: Radiozoa.
Contains: Popofskyelloidea, Cessipyloroidea, Pylentonemoidea, Archipilioidea, Acropyramidoidea, Lychnocanioidea, Eucyrtidioidea, Stichocapsoidea, Amphipyndacioidea, Cannobotryoidea, Triospyrididae, Acanthodesmiidae.

The Nassellaria is a major group of radiolarians known from the Cambrian to the present, with a heteropolar or bilaterally symmetrical skeleton comprising an inner frame and an external shell (Afanasieva et al. 2005).

Characters (from Afanasieva et al. 2005): Heteropolar or bilaterally symmetrical. Skeleton based on inner frame in shape of hollow sphere, polyhedron or spicule, and external shell (conical, pyramidal, spindle-shaped, bell-shaped, helmet-shaped, cap-shaped, or differently shaped test or external skeleton), often segmented. External skeleton subdivided into four main portions: cephalis, thorax, abdomen, and postabdomen. Postabdomen may be further segmented (2–15 or more segments). Inner skeletal polyhedron (5–30 μm in diameter) and spicule included in cephalis, median bar of spicule separating cephalis from thorax. Number and position of rays (spines) of spicule stable: spines A, D, and 2l arising from one end of median bar (MB), spines V, 2L, and Ax extending from another end.

Nassellaria [Nassellarida]
    |--Pylomariata AA05
    |    |--Popofskyelloidea AA05
    |    |--+--Cessipyloroidea AA05
    |    |  `--Pylentonemoidea AA05
    |    `--Proventocitidae [Proventocitoidea] AA05
    |         |--Procyrtis Li 1995 AA05
    |         |--Ulcundia Nazarov 1974 AA05
    |         |    `--U. incomperta AA05
    |         `--Proventocitum Nazarov & Ormiston 1990 AA05
    |              `--P. procerullum AA05
    |--Cyrtidinata [Cyrtoidea] AA05
    |    |  i. s.: Anthocyrtium Haeckel 1887 H04, AA05
    |    |           `--A. campanula H04
    |    |         Alacorys Haeckel 1881 H04, AA05
    |    |           `--A. bismarckii H04
    |    |--Archipilioidea AA05
    |    |--Acropyramidoidea AA05
    |    |--Lychnocanioidea AA05
    |    |--Eucyrtidioidea AA05
    |    |--Stichocapsoidea AA05
    |    |--Amphipyndacioidea AA05
    |    `--Cannobotryoidea AA05
    `--Spyridinata [Spyroidea, Stephaniicae, Stephoidea] AA05
         |  i. s.: Clathrospyris Haeckel 1881 H04, AA05
         |           `--C. pyramidalis H04
         |         Pylospyris Haeckel 1881 H04, AA05
         |           `--P. canariensis H04
         |         Sepalospyris Haeckel 1881 H04, AA05
         |           `--S. pagoda H04
         |         Dictyospyris Ehrenberg 1847 H04, AA05
         |           |--D. anthophora H04
         |           `--D. stalactites H04
         |         Elaphospyris Haeckel 1881 H04, AA05
         |           `--E. cervicornis H04
         |--Triospyrididae AA05
         |--Acanthodesmiidae AA05
         `--Stephaniidae AA05
              |--Cortina Haeckel 1881 AA05
              |--Plagiocarpa Haeckel 1881 AA05
              |--Stephanium Haeckel 1887 AA05
              |    `--S. quadrupes AA05
              `--Zygocircus Buetschli 1882 AA05
                   `--Z. productus AA05

Nassellaria incertae sedis:
  Fuelopicyrtis Kozur & Mostler 1981 DZ03
  Recoaroella Dumitrica 1982 DZ03
  Corocalyptra Haeckel 1887 BC98, AA05
    `--C. craspedota (Jørgensen 1900) BC98
  Peridium Haeckel 1881 BC98, AA05
    `--P. longispinum Jørgensen 1900 BC98
  Acanthocorys Haeckel 1882 BC98, AA05
    `--A. umbellifera (Haeckel 1862) BC98
  Dorypylidae BW04
    |--Dorypyle Squinabol 1904 BW04
    |    `--D. communis (Squinabol 1903) BW04
    `--Hiscocapsa O’Dogherty 1994 BW04
         `--H. asseni (Tan 1927) BW04
  Tertoniidae DZ03
    |--Tertonium Dumitrica & Zügel 2003 DZ03
    |    |--*T. rectum Dumitrica & Zügel 2003 DZ03
    |    `--T. curvicornum Dumitrica & Zügel 2003 DZ03
    `--Toritenum Dumitrica & Zügel 2003 DZ03
         |--*T. hirsutum Dumitrica & Zügel 2003 DZ03
         |--T. corpulentum Dumitrica & Zügel 2003 DZ03
         `--‘Parvicingula’ obesa Takemura 1986 DZ03
  Artostrobus Haeckel 1881 BC98, AA05
    |--A. annulatus (Bailey 1856) BC98
    `--A. joergenseni Petrushevskaya 1971 BC98

*Type species of generic name indicated

REFERENCES

[AA05] Afanasieva, M. S., E. O. Amon, Y. V. Agarkov & D. S. Boltovskoy. 2005. Radiolarians in the geological record. Paleontological Journal 39 (Suppl. 3): S135–S392.

[BW04] Babazadeh, S. A., & P. de Wever. 2004. Early Cretaceous radiolarian assemblages from radiolarites in the Sistan Suture (eastern Iran). Geodiversitas 26 (2): 185–206.

[BC98] Bjørklund, K. R., G. Cortese, N. Swanberg & H. J. Schrader. 1998. Radiolarian faunal provinces in surface sediments of the Greenland, Iceland and Norwegian (GIN) Seas. Marine Micropalaeontology 35: 105–140.

[DZ03] Dumitrica, P., & P. Zügel. 2003. Lower Tithonian mono- and dicyrtid Nassellaria (Radiolaria) from the Solnhofen area (southern Germany). Geodiversitas 25 (1): 5–72.

[H04] Haeckel, E. 1899–1904. Kunstformen der Natur. Bibliographisches Institut: Leipzig und Wien.