Lithraphidites pugio Aguado in Aguado, Company, O'Dogherty, Sandoval & Martinez

Plant Fossil Names Registry Number: PFN001013

Act LSID: urn:lsid:plantfossilnames.org:act:1013

Author: R. Aguado Merlo

Rank: species

Reference: Aguado, R., Company, M., O'Dogherty, L., Sandoval, J. & Martinez, M. (2022): New insights into the Barremian–lower Aptian calcareous nannofossils of the Mediterranean Tethys: Chronostratigraphic and paleobiogeographic implications. – Marine Micropaleontology 173: 102114 (24 pp.).

Page of description: 20

Illustrations or figures: figs 12I-M, 13A-E

Types

Original diagnosis/description

Diagnosis: Very large (13.4–23.5 μm) Lithraphidites nannolith having an outline similar to a short bladed dagger. In the direction opposite to the ‘handle’, the outline is convex and quickly decreases its width before tapering toward the point. The maximum width oscillates between 4.5 and 8.1 μm.

Description: Calcareous rods with cruciform cross-section which are built of long blades of identical optical orientation. The outline is similar to a bladed dagger in which the ‘handle’ (~1.1 μm width and frequently missing by breakage) is followed by a wider expansion (4.5–8.1 μm width) which nearly maintains its width a short distance (around a half of the nannolith length) before quickly tapering toward the point. The L/W ratio is smaller than 3.5 (average 2.9).

Dimensions: length = 13.4–23.5 (average 18.1) μm; width = 4.5–8.1 (average 6.2) μm; specimens measured: 48.

Holotype dimensions: length = 19.6 μm, width = 7.8 μm.

Etymology

From the Latin word ‘pugio’, the double-edged, straight short dagger used by the ancient Romans, whose outline resembles that of this species.

Stratigraphy

Cretaceous, Lower Cretaceous, Barremian
Type level: Uppermost Barremian, sample X.Kv2-228 (NC5E nannofossil Zone; lowermost part of the Gerhardtia sartousiana ammonite Subzone).

Occurrence: In the Subbetic domain of the Betic Cordillera, L. pugio has been recorded throughout part of the upper Barremian (from the middle part of the Gassendiceras alpinum Subzone to the uppermost part of the Hemihoplites feraudianus ammonite Subzone; upper part of NC5E to basal part of NC6A calcareous nannofossil subzones). This species is scarce, but has a consistent record in the calcareous nannofossil assemblages from the X.F, X.HA, X.Kv, X.Kv2 and X.V1 sections. Martinez et al. (2020) used the FO of this species to correlate the uppermost part of the X.V1 and the lowermost part of the X.Kv2 sections. This bioevent has shown biostratigraphic potential to be used in correlation, at least at a regional scale.

Locality

Spain
Type locality: X.Kv2 section (38.053 N; 1.889 W), Province of Murcia, southeastern Spain.