Argentinopora robusta n. gen., n. sp.

(Figs 11 F-G; 12A-F; Appendix 1)

urn:lsid:zoobank.org:act: 51DCA703-84A9-4080-8A78-D507D5D6D0FC

HOLOTYPE. — CEGH-UNC 27511 a-d (one colony, four thin sections).

PARATYPES. — CEGH-UNC 27514 a-c, CEGH-UNC 27515 a, CEGH-UNC 27520 a, b.

TYPE LOCALITY. — La Pola creek section near Albardon village, San Juan Province, Argentine Precordillera, western Argentina.

TYPE HORIZON. — La Pola Formation, Upper Ordovician, Sandbian.

DIAGNOSIS. — As for genus.

ETYMOLOGY. — The species name refers to its thick walls and large mesozooecia and acanthostyles (from Latin “ robustus ” – robust, stable, strong).

DESCRIPTION

Ramose colony with multiple secondary overgrowths, 3.5- 11.0 mm in diameter, with 0.72.– 1.44 mm wide exozones. Secondary overgrowths 1.05-2.00 mm thick. Autozooecial apertures rounded-polygonal, often petaloid.Basal diaphragms abundant, straight or inclined throughout autozooecia.Cystiph - ragms common in exozones. Mesozooecia abundant, 3-7 surrounding each autozooecial aperture, originating in the early exozone, large, cystose, containing thick diaphragms. Acanthostyles large, abundant, 5-8 surrounding each autozooecial aperture, originating in endozone, having wide hyaline cores and narrow laminated sheaths, often indenting autozooecia and mesozooecia. Autozooecial walls laminated, 0.01-0.03 mm thick in endozones; thickly laminated, merged, without cingulum, 0.04-0.11 mm thick in exozones. Maculae not observed.

COMPARISON

As for genus.