Hamarophyllum belkai, Berkowski, 2004

Berkowski, Błażej, 2004, Monospecific rugosan assemblage from the Emsian hydrothermal vents of Morocco, Acta Palaeontologica Polonica 49 (1), pp. 75-84 : 82-83

publication ID	https://doi.org/ 10.5281/zenodo.13272351
persistent identifier	https://treatment.plazi.org/id/03FC8F2B-FFA2-FFBC-FCA1-9016D7DCF98F
treatment provided by	Felipe
scientific name	Hamarophyllum belkai
status	sp. nov.

Treatment

Hamarophyllum belkai sp. nov.

Figs. 2B View Fig , 3 View Fig , 5 View Fig , 6 View Fig , 9 View Fig .

? Laccophyllum sp. Weyer 1990: 26, fig. 2.

Holotype: Specimen UAM Tc/B HD1/1/1 ( Fig. 9A–G View Fig ).

Paratypes: Specimens UAMTc/B HD27/4/1 ( Fig. 5B–L View Fig ), UAMTc/B HD27/1/1 ( Fig. 9H View Fig ).

Type horizon: Emsian (Zlichovian), Polygnathus inversus conodont zone.

Type locality: Mud mounds of Hamar Laghdad,Tafilalt, Eastern Anti−Atlas, Morocco.

Derivation of the name:InhonorofProfessorZdzisławBełka,whoorganizedexpeditiontoMoroccoin2001and2002wherethespecimens were found.

Diagnosis.— Hamarophyllum with 15–16 wavy major septa at the diameter of 6–8 mm near calice floor. In longitudinal section auliar tabulae are widely spaced, horizontal or delicately convex or concave.

Material.—Hundreds ofspecimens. 21 specimens were sectioned: 47 transverse and 6 longitudinal thin sections have been made.

Description.—Corallitesare smalland horn−shaped. Calices are deep, septal furrows and interseptal ridges are observed on the external wall only in mature stages.

External wall is thin in brephic and neanic stages ( Fig. 9A–C View Fig ) and thick and lamellar in mature stages ( Fig. 9D–G View Fig ). Majorseptaarelongreaching2/3–4/5ofthecoralliteradius. They are wavy and rhopaloid, forming a constant and thickenedaulos.Aulosisoccupying1/4–1/5ofthecorallitediameter ( Fig. 9A–E View Fig ). Cardinal septum is as long as adjacent septa;counterseptummaybesomewhatelongated.Cardinal fossulaisveryshallow,andnotwellmarked.Septalsplitting ofcardinal,counter,oralarseptaisnotobserved.Mostofminor septa reach 1/3 length of major septa. They are mostly contratingent, but they may be also contratingent or free especially in mature stages.

Tabularium is biform. Periauliar tabellae in position I subhorizontal or slightly declined adaxially, in position II theyaredeclinedabaxially,slopingdownoutward( Fig.9H View Fig ).

Tabellae in the aulos are flat not densely packed 4–5/ 5 mm ( Fig. 9H View Fig )

Microstructure of wall is lamellar, whereas septal microstructure is not well preserved, contains trabecular relics.

Ontogeny.—The earliest stages are aseptal (circular basal disk). In the six septal stage septa are straight and united in the axis. A minute aulos is formed early, when the next four majorseptaappear.Minorseptabegintoappearwhen10–14 major septa are inserted and are mostly contratingent ( Fig. 9B View Fig ). Contratingency of minor septa may disappear in later stages when they become contraclined or free ( Fig. 9E View Fig ). They may be either slightly wavy or straight.

Intraspecific variability.—Displaying mostly in the exteral shape, which is often caused by the restricted space of growth. The proximal part of the skeleton is radiciform of various shapes depending on the place of attachment. The shape of the transversal section of young skeleton in the caliceofextinctindividualinplacewhereitisattachedatthe early stages of ontogeny follows the shape of the empty calice. Internal structures vary in thickness and swellings of majorseptaandthediameterofaulos,whichmaybemoreor less wide in neanic stages.

Occurrence.—Venting fields of Hamar Laghdad mud mounds,Tafilalt,EasternAnti−AtlasMorocco.Emsian Polygnathus inversus conodont zone.