Longing Gap Radiolarians, K 13 (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 51836: authorized by Wolfgang Kiessling, entered by Wolfgang Kiessling on 22.06.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

Protozoa
 Spumellaria - Emiluviidae
Emiluvia hopsoni Pessagno 1977 radiolarian
Emiluvia aff. hopsoni Pessagno 1977 radiolarian
 Spumellaria -
 Spumellaria - Hagiastridae
Higumastra devilsgapensis Pessagno et al. 1993 radiolarian
s.l.
 Spumellaria - Parvivaccidae
Acaeniotyle parva Yang 1993 radiolarian
Acaeniotyle umbilicata RĂ¼st 1898 radiolarian
 Spumellaria - Pantanelliidae
Pantanellium formosum Yang 1993 radiolarian
Pantanellium aff. formosum Yang 1993 radiolarian
Pantanellium deflectum Yang 1993 radiolarian
Pantanellium rarum Hull 1997 radiolarian
Pantanellium aff. parvulum Pessagno and MacLeod 1987 radiolarian
 Spumellaria - Orbiculiformidae
Orbiculiforma cf. quadrata Pessagno 1973 radiolarian
 Radiolaria - Actinommidae
Actinomma frigida Kiessling 1999 radiolarian
Actinomma verwirra Kiessling 1999 radiolarian
 Actinommacea - Xiphostylidae
Tripocyclia crassa Kiessling 1999 radiolarian
Suna cf. harperi Pessagno et al. 1989 radiolarian
Triactoma mexicana Pessagno et al. 1989 radiolarian
 Nassellaria - Parvicingulidae
Caneta hsui Pessagno 1977 radiolarian
Parvicingula excelsa Pessagno and Blome 1984 radiolarian
Parvicingula colemani Pessagno and Blome 1984 radiolarian
Parvicingula jonesi Pessagno 1977 radiolarian
s.l.
Praeparvicingula "B" Pessagno et al. 1993 radiolarian
Praeparvicingula blomei Yang 1993 radiolarian
Praeparvicingula vera Pessagno and Whalen 1982 radiolarian
Praeparvicingula rotunda Hull 1995 radiolarian
 Nassellaria - Amphipyndacidae
Triversus fastigatus Hull 1997 radiolarian
 Nassellaria - Ultranaporidae
Napora pualensis Blome 1984 radiolarian
Napora durhami Pessagno 1977 radiolarian
 Nassellaria - Sethocapsidae
Sethocapsa trachyostraca Foreman 1973 radiolarian
 Nassellaria - Eucyrtiidae
"Tetracapasa molengraaffi" = Tetracapsa
"Tetracapasa molengraaffi" = Tetracapsa radiolarian
 Nassellaria - Tripedurnulidae
Pseudopoulpus "A" Takemura 1986 radiolarian
 Entactinaria - Eptingiidae
Perispyridium sp. Dumitrica 1978 radiolarian
Perispyridium ordinarium Pessagno 1977 radiolarian