New serpulid polychaetes from the Permian of western Sicily ROSSANA SANFILIPPO, ANTONIETTA ROSSO, AGATINO REITANO, ALFIO VIOLA, and GIANNI INSACCO Sanfilippo, R., Rosso, A., Reitano, A., Viola, A., and Insacco, G. 2018. New serpulid polychaetes from the Permian of western Sicily. Acta Palaeontologica Polonica 63 (3): 579–584. Two new tubeworms, “Serpula” calannai sp. nov. and “Serpula” prisca sp. nov. are described from the Permian lime- stone of the Sosio Valley, western Sicily. Both species possess large tubes with long free anterior portions circular in cross-section. All morphological characters, such as tube shape and ornamentation, as well as inner structure of the wall, even if barely visible due to diagenesis, are still preserved. These two new species increase the previously known diver- sity of the Permian serpulid community, which flourished at the shelf edge of the western sector of the Palaeotethys and disappeared thereafter. The likely Wordian age of these serpulids, and their presumed absence in younger rocks up to the Middle–Late Triassic, suggests reduction, or even extinction, of these reef-related serpulid taxa during the end-Guada- lupian biotic crisis, before the end-Permian extinction. Key words: Polychaeta, Serpulidae, tube morphology, reef community, extinction events, Palaeozoic, Permian, Italy. Rossana Sanfilippo [[email protected]], Antonietta Rosso [[email protected]], and Alfio Viola [[email protected]], Department of Biological, Geological and Environmental Sciences, University of Catania, Corso Italia 57, 95129 Catania, Italy. Agatino Reitano [[email protected]] and Gianni Insacco [[email protected]], Museo di Storia Natu- rale di Comiso, Via degli Studi 9, 97013 Comiso, Italy. Received 2 December 2017, accepted 16 May 2018, available online 8 August 2018. Copyright © 2018 R. Sanfilippo et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. leontological museums in Sicily. They originate from the Introduction same Permian rocks, specifically the “Pietra di Salomone” True serpulids are commonly found in the fossil record Limestone from the Sosio Valley, western Sicily. These new and until recently they were considered widely distributed specimens consist of the long unattached anterior parts of throughout the Mesozoic and Cenozoic, with about 46 gen- large tubes, circular in cross section. era and 350 species (ten Hove and Kupriyanova 2009; Kočí The aims of this study are to: (i) describe these new and Jäger 2015, among others). Small and simple forms dat- species; (ii) determine affinities and differences between ing back to the Middle Triassic, ca. 244 Ma, are the first the new species and the serpulid taxa already known from records of unequivocal serpulids, although a number of the same area and time span; (iii) discuss the role played by problematic tubeworms of presumed serpulid affinity were the serpulid community of the Sosio Limestone within reef reported from the Permian on (see Ippolitov et al. 2014). palaeoenvironments of the Permian Mediterranean Palaeo- However, unexpected large-sized species with advanced tethys. characters, such as complex shape and ornamentation, were recently discovered in a limestone bed dated back to the Institutional abbreviations.—PMC, Museo di Paleontologia, middle-to-upper Permian, ca. 268–251 Ma (Sanfilippo et University of Catania, Italy; MCSNC, Museo Civico di al. 2016, 2017b). These findings antedated serpulids’ first Storia Naturale di Comiso, Ragusa, Italy. appearance even several millions years earlier and indicated that a surprisingly diversified serpulid community existed before the end-Permian mass extinction. Material and methods Two further new species unequivocally belonging to the serpulids, namely “Serpula” calannai sp. nov. and “Serpula” The two specimens examined in the present paper originate prisca sp. nov., were found in materials deposited in pa- from the “Pietra di Salomone” Limestone (Fig. 1), the larg- Acta Palaeontol. Pol. 63 (3): 579–584, 2018 https://doi.org/10.4202/app.00448.2017 580 ACTA PALAEONTOLOGICA POLONICA 63 (3), 2018 Palazzo A B Low magnification photos were acquired with a Zeiss Adriano Palazzo Discovery V8A stereomicroscope equipped with an Axio- N 500 m Adriano Mediterranean vision acquisition system in order to document general tube Sea SICILY morphology. Both specimens and the detached fragment sandy clay, arenite and globigerind were also examined uncoated under a LMU Tescan Vega 30° marl (Oligocene–Middle Miocene) globigerinid limestone “Scaglia” Scanning Electron Microscope in Low Vacuum modality to (Early Cretacaeous – Eocene) investigate their micromorphology and microstructure. pelagic limestone and radiolarite (Jurassic) “Serpula” calannai sp. nov. is stored in the Collection limestone blocks Mario Calanna of the MCSNC, while “S.” prisca sp. nov. is (Permian–Triassic) San Calogero Flysh stored in the collections of the PMC. Pietra di (Middle–Late Permian) Salomone marl, calcilutite, cherty limestone withHalobia (Carnian–Rhaetian) tectonic boundary dipping 30° axis of syncline Systematic palaeontology T. San CalogeroSan main thrust fault road Class Polychaeta Grube, 1850 Family Serpulidae Rafinesque, 1815 40° Genus Serpula Linnaeus, 1758 C Type species: Serpula vermicularis Linnaeus, 1767; Recent of England. Fig. 1. A, B. Location of the study area in the Mediterranean and Sicily. “Serpula” calannai sp. nov. C. Geological map of the Palazzo Adriano area (Sicani Mountains) show- Figs. 2, 3A–F. ing the location of the “Pietra di Salomone” megablock (modified from Di Etymology: In honor of the paleontology amateur collector the late Stefano and Gullo 1997). Mario Calanna (1945–2014), for his contribution to natural history est fossiliferous megablock (200 m long, 100 m wide and collections, especially in malacology. 30 m high) among those cropping out near Palazzo Adriano Holotype: MSNC 4549-33, one large tube portion (44 mm long and in the Sicani Mountains, western Sicily (for geological de- 7.8 mm wide), representing part of an unattached anterior erect portion, broken at both ends and partially filled by lithified sediment. tails see Sanfilippo et al. 2017b, and references therein). It Type locality: Sosio Valley, western Sicily, Italy. consists of a coarse calcareous breccia of which the precise age is still debated, being referred to the Wordian by Flügel Type horizon: “Pietra di Salomone” Limestone, Wordian to upper Permian (see Material and methods). et al. (1991), but considered, at least partly, Capitanian, Wuchiapingian or even Changhsingian by Jenny-Deshusses Material.—Type material only. et al. (2000). Diagnosis.—Tube quite large, with a well-developed raised The fossiliferous content of these Permian megablocks anterior end, circular in cross-section, with outer surface fee- is famous world-wide for its rich invertebrate fauna, first bly rough. Ornamentations solely consisting of eristomes well discovered and described by Gemmellaro (1887–1889). In developed and slightly flaring. Tube wall thick and layered. total, more than 300 species are known from the “Pietra di Description.—The single available specimen is a large tube Salomone” alone, belonging to several taxonomic groups portion of the anterior end, 44 mm long and 7.8 mm wide. It such as sponges, corals, bryozoans, brachiopods, as well as is slightly bent and circular in cross-section, not increasing to the recently discovered serpulids (see Flügel et al. 1991; in diameter. Outer surface is feebly lumpy to smooth, with Sanfilippo et al. 2016, 2017b, and references therein). Like only irregular and inconspicuous growth lines, which are previously described serpulids, the two new species were about 10 μm thick. Peristomes are well developed, differ- included in the white crinoid-rich limestone from the up- ently pronounced and slightly flaring, with smooth, circular per part of the “Pietra di Salomone”. Serpulid tubes were edges, locally crenulated. Peristomes are protruding up to mainly found attached to sponges, while the species de- scribed herein are broken off parts of unattached anterior 300 μm and irregularly spaced, at intervals of 2–6 mm. ends found embedded in the carbonate rock. Tube wall is about 600 μm thick, with a seemingly layered The fragments belonging to “Serpula” calannai sp. nov. internal structure, as barely visible along some sections, were separated mechanically from the slightly cemented which cross areas that are not completely altered by recrys- calcilutite, and glued together to reconstruct a longer, al- tallization. Posterior (attached) tube portion is lacking. though broken, tube part. The tube was accurately cleaned Remarks.—The combination of tube characters of “Serpula” to examine the whole external surface and broken longi- calannai sp. nov. are considered sufficient to describe it as tudinally at one end to investigate its microstructure. The a new species. Particularly, this species clearly differs from tube belonging to “S.” prisca sp. nov. was cleaned, but not the other five serpulids recently mentioned from the same extracted from the enclosing rock, to avoid the separation of area (Sanfilippo et al. 2016, 2017b) by the relevant size of tube portions glued together in an old restoration. the tube, which is significantly larger and thicker