Leioclema arauzensis, 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 : 710-712

Leioclema arauzensis n. sp. ( Fig. 11 B-G; Appendix)

HOLOTYPE. — SMF 21.212 .

PARATYPES. — SMF 21.213- SMF 21.220.

ETYMOLOGY. — The species name refers to Arauz Sur, the locality where the new species was found.

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

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

OCCURRENCE. — Lebanza Formation, Lower Devonian (Pragian); Arauz Sur (Arroyo section), Palencia, NW-Spain (Cantabrian Mountains). Lower Devonian (Emsian); Altai Mountains, Russia. Lower Devonian (Pragian-Emsian); Mongolia.

DIAGNOSIS. — Encrusting colonies; autozooecial diaphragms few to absent; 2-5 mesozooecia surrounding each aperture; 2-6 moderately large acanthostyles surrounding each aperture.

DESCRIPTION

Encrusting colonies, 0.48-0.96mm in thickness.Autozooecia budding from a thin epitheca,briefly oriented parallel to the substrate, then bending sharply and intersecting the colony surface at right angles. Autozooecial apertures rounded-polygonal to petaloid due to indenting acanthostyles.Autozooecial diaphragms few to absent, thin, straight or slightly deflected proximally. Mesozooecia abundant, 2-5 surrounding each aperture, polygonal in cross section, slightly beaded, containing planar diaphragms.Acanthostyles moderately large, abundant, 2-6 surrounding each aperture, originating from the base of exozone, often indenting autozooecia,having distinct calcite cores and dark laminated sheaths.Walls granular, in endozone 0.010 -0.015 mm thick; in exozone 0.025 -0.065 mm thick, distinctly laminated. Maculae not observed.

COMPARISON

Leioclema arauzensis n. sp. is similar to L. passitabulatum Duncan, 1939 from the Lower-Middle Devonian of USA and Europe, but differs in having fewer mesozooecia (2-5 vs 4-10 mesozooecia around autozooecial aperture in L. passitabulatum ).

Figures

FIG. 11. — A, Neotrematopora tenuis n. sp., longitudinal section showing mesozooecium and zooecial walls, paratype SMF 21.211; B-G, Leioclema arauzensis n. sp.; B, tangential section showing autozooecial apertures, mesozooecia and abundant acanthostyles, holotype SMF 21.212; C, longitudinal section showing autozooecia and mesozooecia with diaphragms, holotype SMF 21.212; D, E, longitudinal section showing autozooecia with diaphragms and mesozooecia, paratype SMF 21.218; F, longitudinal section, paratype SMF 21.219; G, tangential section, paratype SMF 21.215. Scale bars: A, B, 0.2 mm; C-G, 0.5 mm.