Longing Gap Radiolarians, K 6 (Jurassic of Antarctica)

Where: Antarctic Peninsula, Antarctica (64.5° S, 59.0° W: paleocoordinates 55.0° S, 33.2° W)

• hand sample-level geographic resolution

When: Longing Member (Ameghino Formation), Late/Upper Kimmeridgian (155.7 - 150.8 Ma)

• bed-level stratigraphic resolution

Environment/lithology: basinal (); lithified, concretionary, black mudstone

• Anoxic conditions prevailed especially in the Longing Member; this is indicated by the often lacking bioturbation and rare horizons with benthonic fossils. In the Ameghino Member moderately intense bioturbation (Zoophycos, Chondrites, Planolites) and a consequent destruction of lamination indicate dysaerobic conditions. Doyle and Whitham (1991) attribute this environmental change to an uplift of the depositional environment above a permanent pyknocline. The submarine relief was very low and a simple hemipelagic sedimentation was dominant.
• Mudstone concretion with tuff layers

Size class: microfossils

Preservation: concretion, replaced with other

Collection methods: bulk, chemical, hydrochloric, sieve,

• Radiolarians only. Additional faunal elements are sponge spicules and very rare foraminifera.

Primary reference: W. Kiessling, R. Scasso, A. Zeiss, A. Riccardi, and F. Medina. 1999. Combined radiolarian-ammonite stratigraphy for the Late Jurassic of the Antarctic Peninsula: Implications for radiolarian stratigraphy. Geodiversitas 21(4):687-713 [W. Kiessling/W. Kiessling/W. Kiessling]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 51833: authorized by Wolfgang Kiessling, entered by Wolfgang Kiessling on 22.06.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Protozoa
 Actinommacea - Xiphostylidae
Triactoma mexicana
Triactoma mexicana Pessagno et al. 1989 radiolarian
 Nassellaria - Eucyrtidiidae
? Solenotryma "A"
? Solenotryma "A" Foreman 1968 radiolarian
 Nassellaria - Amphipyndacidae
Triversus fastigatus
Triversus fastigatus Hull 1997 radiolarian
 Nassellaria - Parvicingulidae
Praeparvicingula "B", Praeparvicingula rotunda, Caneta hsui, Parvicingula jonesi
Praeparvicingula "B" Pessagno et al. 1993 radiolarian
Praeparvicingula rotunda Hull 1995 radiolarian
Caneta hsui Pessagno 1977 radiolarian
Parvicingula jonesi Pessagno 1977 radiolarian
 Nassellaria - Sethocapsidae
Gongylothorax favosus
Gongylothorax favosus Dumitrica 1970 radiolarian
 Nassellaria - Williriedellidae
Zhamoidellum ventricosum
Zhamoidellum ventricosum Dumitrica 1970 radiolarian
 Entactinaria - Eptingiidae
Perispyridium sp., Perispyridium ordinarium
Perispyridium sp. Dumitrica 1978 radiolarian
Perispyridium ordinarium Pessagno 1977 radiolarian
 Spumellaria - Pantanelliidae
Protovallupus vaticinus, Protovallupus cf. vaticinus
Protovallupus vaticinus Pessagno and MacLeod 1987 radiolarian
Protovallupus cf. vaticinus Pessagno and MacLeod 1987 radiolarian
 Spumellaria - Hagiastridae
Higumastra scassoi, Crucella theokaftensis
Higumastra scassoi Kiessling 1999 radiolarian
Crucella theokaftensis Baumgartner 1980 radiolarian
 Spumellaria - Praeconocaryommidae
Praeconocaryomma scatebra, ? Praeconocaryomma matsuokai
Praeconocaryomma scatebra Hull 1997 radiolarian
? Praeconocaryomma matsuokai Kiessling 1999 radiolarian
 Spumellaria - Emiluviidae
Emiluvia hopsoni
Emiluvia hopsoni Pessagno 1977 radiolarian
 Spumellaria - Parvivaccidae
Acaeniotyle umbilicata
Acaeniotyle umbilicata Rüst 1898 radiolarian