Serpulidae, Rafinesque, 1815

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 : 33

Serpulidae gen. et sp. indet.

Fig. 8 .

Material.— A fragment, broken at both ends, of a presumably adult, straight free anterior tube portion ( MSNC 4531 ) originating from “Pietra di Salomone” Limestone, the Sosio Valley , western Sicily ( Italy); Wordian to upper Permian .

Description. —The sole collected specimen is 9.5 mm long and 2.9 mm in cross section and appears entirely recrystallized. It consists of a tube fragment corresponding to an anterior tube portion. It is rather massive and solid, circular in cross-section with a constant diameter of 2.9 mm. Lumen 2.4 mm wide. Tube wall thick (0.3 mm). Outer surface smooth, except for densely situated thin but distinct circular growth lines, equally spaced. Some more marked growth lines may be interpreted as weak annular peristomes, although there is no obvious difference between growth lines and peristomes. Posterior encrusting tube portion unknown. Large secondary calcite crystals occur in the tube wall, whose original structure is totally biased by diagenetic recrystallization.

Remarks.—The specimen exhibits unequivocal serpulid characters, which are otherwise too poor for specific and generic assignment.

Figures

Fig. 8. Serpulidae sp. indet. from the Sosio Valley, western Sicily (Italy), Wordian to upper Permian, MSNC 4531. A. Tube fragment of the anterior erect part, broken at both ends. B. Detail of the outer surface showing thin and straight growth lines. C. Circular cross-section of the tube displaying the wall thickness; the lumen of the tube is filled by lithified sediment. D. Micromorphology on the outer surface under SEM image magnification: a straight peristome extremely feeble and thin growth lines equally spaced are obvious. E. Detail of one tube end showing the wall thickness (ca. 0.3 mm).