Glomerula gemmellaroi, Sanfilippo & Rosso & Reitano & Insacco, 2017

Sanfilippo, Rossana, Rosso, Antonietta, Reitano, Agatino & Insacco, Gianni, 2017, First record of sabellid and serpulid polychaetes from the Permian of Sicily, Acta Palaeontologica Polonica 62 (1), pp. 25-38 : 28-29

Glomerula gemmellaroi sp. nov.

Fig. 2D–F .

Etymology: Named after Professor Gaetano Giorgio Gemmellaro (1832–1904), who discovered and first studied the Permian fossiliferous limestone rocks of the Sosio Valley.

Type material: Holotype: single tube curved at different angles attached for all of its length on a sponge ( MSNC4519 ) . Paratypes: single slightly curved incomplete tubes: two on sponges ( MSNC 4520 , MSNC 4521 ), one on a stromatoporoid ( MSNC 4522 ), and one on a brachiopod shell ( MSNC 4523 ). All specimens come from the “ Pietra di Salomone ” megablock, except for specimen MSNC 4522 originating from the “ Rupe di San Calogero ” mebablock .

Type locality: Sosio Valley , western Sicily ( Italy) .

Type horizon: “Pietra di Salomone” Limestone, Wordian to upper Permian.

Diagnosis.—Tube long in respect to its width, circular in cross-section and smooth, increasing in diameter slowly. Base of the tube not widened by a basal cementing flange. Tubes more or less irregularly curved, but never forming spirals or knots.

Description.—Tubes small-sized (outer diameter of 0.2–0.25 mm), the outer surface smooth, only at places marked by feeble growth lines. Tubes are weakly attached to the substrate for all their length, isolated and irregularly curved, sometimes forming close meanders angled more typically at 90° and 180°. Aggregates of aligned to irregularly coiled tubes also occur. An obvious recrystallization affects the specimens, their original tube wall structure being totally biased.

Remarks.—The present species has been assigned to Glomerula because of its small-sized smooth tubes, circular in cross-section and slowly increasing in diameter, and the general development included in the generic diagnosis. The particular meandering and the bending angles clearly differentiate these tubes from those of G. testatrix in the studied collection, and from other species in the genus.

Stratigraphic and geographic range.—Wordian to upper Permian of Italy.

Figures

Fig. 2. Sabellids from literature (A) and from study material (B–F). A. Holotype of Serpula testatrix Etheridge, 1892 (pl. 18: 5) on a crinoid stem from East Maitland (South Wales), Permo-Carboniferous, showing typical loose loops and spirals. B, C. Glomerula testatrix (Etheridge, 1892) Sanfilippo comb. nov., from the Sosio Valley, western Sicily (Italy), Wordian to upper Permian. B. MSNC 4515, irregular glomerate interweaving tubes; photograph (B1), SEM image (B2); B3, detail of B2, showing the tube outer surface with feeble growth lines. C. MSNC 4518, set of sub-parallel tubes slightly meandering and locally forming a sharp bend encrusting a sponge. D–F. Glomerula gemmellaroi sp. nov. from the Sosio Valley, western Sicily (Italy), Wordian to upper Permian. D. MSNC 4519, holotype, specimen forming meanders and bending at angles of 90° and 180°. E. MSNC 4520, tube initially loop-like curved and then bent at right angle. F. MSNC 4521, meandering tube on a sponge.