Altshedata gracilis, Ernst & Fernández & Fernández-Martínez & Vera, 2012

Ernst, Andrej, Fernández, Luis Pedro, Fernández-Martínez, Esperanza & Vera, Carmen, 2012, Description of a bryozoan fauna from mud mounds of the Lebanza Formation (Lower Devonian) in the Arauz area (Pisuerga-Carrión Province, Cantabrian Zone, NW Spain), Geodiversitas 34 (4), pp. 693-738 : 700-704

publication ID

https://doi.org/ 10.5252/g2012n4a1

persistent identifier

https://treatment.plazi.org/id/03A6D074-FFE8-7E18-FCC6-F9EDFF26F93D

treatment provided by

Marcus

scientific name

Altshedata gracilis
status

sp. nov.

Altshedata gracilis n. sp. ( Figs 6 View FIG D-G, 7A-D; Appendix)

HOLOTYPE. — SMF 21.150 About SMF . PARATYPES. — SMF 21.151- SMF 21.164.

ETYMOLOGY. — The species name refers to the small sizes of colonies and autozooecia of the new species (derived from Latin “ gracilis ” = slender).

TYPE LOCALITY. — Arauz Sur (Arroyo section), Province of Palencia, NW-Spain (Cantabrian Mountains).

TYPE HORIZON. — Lebanza Formation, Lower Devonian (Pragian).

DIAGNOSIS. — Encrusting colonies; autozooecia prismatic; autozooecial diaphragms common, straight, thin; lunaria well-developed, prominent; megazooecia or other heterozooecia not observed; vesicles occasionally present, never isolating autozooecia; communication pores absent; maculae not observed.

DESCRIPTION

Encrusting colonies, 0.9-1.2 mm thick. Autozooecia prismatic, budding from the basal epitheca, hemispherical to trapezoidal at their bases, becoming rhombic to hexagonal, recumbent in proximal parts, then bending sharply and intersecting colony surface at right angles. Autozooecial diaphragms common, straight, thin, locally absent. Autozooecial apertures rounded-polygonal. Lunaria well-developed, prominent, rounded, deeply indenting autozooecial cavity, originating from bases of autozooecia, consisting of hyaline material. Heterozooecia not observed. Vesicles rarely present, irregular in shape and size, occurring at the base of exozone. Autozooecial walls in the endozone granular, straight, 0.005 -0.010 mm thick; in exozone irregularly thickened, showing indistinct granular microstructure with deep annulations, 0.03-0.05 mm thick. Short style-like projections present in autozooecial walls and in the granular skeleton on the colony surface. Communication pores not observed. Maculae not observed.

COMPARISON

Altshedata gracilis n. sp. differs from Altshedata hispanica n. sp. in having smaller autozooecia (average autozooecial width 0.27 vs 0.3 mm in A. hispanica ), presence of megazooecia and the absence of style-like projections in autozooecial walls.

SMF

Forschungsinstitut und Natur-Museum Senckenberg

Darwin Core Archive (for parent article) View in SIBiLS Plain XML RDF