1,721,175 research outputs found
A case of probable drilling predation on a Pliocene turtle barnacle (Crustacea, Thoracica)
No full textBy attaching to motile, long-living substrates, the suspension-feeding turtle and whale barnacles (Coronuloidea; families Chelonibiidae, Coronulidae and Platylepadidae) enjoy a continuous flow of seawater and nutrient particles while also significantly reducing the risk of predation. Consequently, very little (if anything at all) is known about the potential predators of these cirripedes. Here, I show that available illustrations of a compound rostrum from the Pliocene of Gran Canaria, which is the lost type specimen and only known individual of Chelonibia hemisphaerica, feature the presence of a circular, non-penetrative boring on the exterior of the paries. This perforation is interpreted as a drill hole left by a predatory gastropod (most likely a muricid). Although drill holes are relatively frequent in both fossil and Recent acorn barnacle hardparts, this appears to be the first report of such a shell modification in a coronuloid barnacle. The common absence of drill holes on coronuloid shells is explained by the fact that the latter are usually excluded from interaction with gastropods and other predators due to their attachment preference for large, actively swimming hosts. Targeted predation on a living barnacle occurring on a dead/inanimate substrate (or slowly moving host) or erroneous “predation” on an empty dead shell would both seem reasonable explanations for the remarkable occurrence of a drill hole in the type compound rostrum of C. hemisphaerica
Palaeontological heritage of the Monti Pisani massif (northern Apennines, Italy): a compelling history of animals, plants and palaeoenvironments through three geological eras
Full text linkHere I provide an updated synoptic review of the palaeontological heritage of Monti Pisani and anticipate some preliminary perspectives for its geoconservation and sustainable valorization
The occurrence of the coronuloid barnacle Chelonibia Leach, 1817 as an encruster on mammalian bone in the central Mediterranean Sea
Full text linkMeđu kornjačama i kitovima (Coronuloidea: Chelonibiidae, Coronulidae, † Emersoniidae i Platylepadidae), pripadnici vrste Chelonibia testudinaria (Linnaeus, 1758) poznati su kao epizoični brumbuljci koji se mogu pričvrstiti na prilično širok spektar podloga (prvenstveno na kornjače, rakove i velike vodene sisavce koji se hrane biljkama iz reda Sirenia). Trenutno su prepoznate tri živa morfija C. testudinaria; od njih, manje specifična za domaćina je morph patula, koja također prikazuje izuzetno jednostavnu, nespecijaliziranu arhitekturu ljuske. U ovom radu izvještavamo o nekoliko ljuski helonibiida, koje se odnose na morfe patule C. testudinaria, koja inkrustira lopaticu kitova sakupljenu s dna Jadranskog mora prema Salentu (regija Apulia, jugoistočna Italija) i okvirno upućenu na Tursiops truncatus (Montagu, 1821). Ovo je jedan od rijetkih zapisa u svijetu o brumbuljku iz nežive podloge, a i kao drugi slučaj inkrustriranja na kosti sisavca. Takva neobična pojava potom se ukratko raspravlja u širem kontekstu komensalizma brumbuljaka i supstrata staništa.Among the turtle and whale barnacles (Coronuloidea: Chelonibiidae, Coronulidae, †Emersoniidae and Platylepadidae), the members of the chelonibiid species Chelonibia testudinaria (Linnaeus, 1758) are known as epizoic barnacles that can attach to a rather wide spectrum of substrates (primarily sea turtles, crabs and sirenians). At present, three living morphs of C. testudinaria have been recognised; of these, the less host-specific is the patula morph, which also displays a remarkably simple, unspecialised shell architecture. Here we report on several chelonibiid shells, referred to the patula morph of C. testudinaria, encrusting a cetacean scapula collected from the floor of the Adriatic Sea facing Salento (Apulia Region, southeastern Italy) and tentatively referred to Tursiops truncatus (Montagu, 1821). This is one of the few records worldwide of a coronuloid barnacle from an inanimate substrate, as well as the second as an encruster on mammalian bone. Such an unusual occurrence is then briefly discussed in the broader framework of the coronuloid commensalism and substrate habits
An overview of the fossil record of cetaceans from the East Pisco Basin (Peru)
No full textThe East Pisco Basin is one of the forearc basins that formed during the Cenozoic along the coast of Peru due to the subduction of the Farrallon-Nazca plate beneath the South American plate. The sedimentary fill of this basin is extensively exposed along the coastal Ica Desert, and includes a succession of Eocene to Pliocene marine sediments that account for a ~50-myr-long history of semicontinuous deposition. These rocks are characterized by an outstanding fossil content that remarkably contributed to our understanding of the evolutionary history of the main groups of Cenozoic marine vertebrates. In the Ica desert, the most common and significant vertebrate remains belong to cetaceans. Knowledge on the fossil cetaceans of the East Pisco Basin has grown dramatically in the last fifteen years thanks to several international research projects involving, among many others, the authors of the present article. These research efforts have led to the discovery of several hundred fossil skeletons, the most significant of which have been collected, prepared and partly published. Furthermore, interdisciplinary studies were also conducted in order to provide a high resolution chronostratigraphic framework for this fossil record. Remarkable cetacean specimens come from the Yumaque member of the Paracas Formation (middle to late Eocene), the Otuma Formation (late Eocene), the Lower Miocene (~19-18 Ma) portion of the Chilcatay Formation, and allomembers P0 (14.8-12.4 Ma), P1 (9.5-8.5 Ma) and P2 (8.4-6.7 Ma) of the Middle Miocene to Pliocene Pisco Formation. The Lutetian (42.6 Ma) Yumaque strata are home to the quadrupedal protocetid archaeocete Peregocetus pacificus, which documents the first arrival of cetaceans in the Pacific Ocean. Geologically younger (36.4 Ma) Yumaque deposits have yielded the holotype skeleton of Mystacodon selenesis, the oldest mysticete ever found. This ancestor of the modern baleen whales had a skull provided with a complete dentition and retained hindlimbs, albeit reduced in size. In the Otuma Formation, a nine-m-long basilosaurid (Cynthiacetus peruvianus) has been discovered. The Chilcatay Formation records the first great radiation of the odontocetes, represented by Inticetidae (Inticetus vertizi), basal Platanidelphidi (Ensidelphis riveroi), Squalodelphinidae (Furcacetus flexirostrum, Huaridelphis raimondii, Macrosqualodelphis ukupachai and Notocetus vanbenedeni), Platanistidae (aff. Araeodelphis), Physeteroidea (Rhaphicetus valenciae and cf. Diaphorocetus), Chilcacetus cavirhinus, indeterminate Eurinodelphinidae, and Kentriodontidae (Kentriodon). Overall, this roughly coeval assemblage displays a considerable disparity in terms of skull shape and body size that is possibly related to the development of different trophic strategies, ranging e.g., from suction to raptorial feeding. In the Pisco Formation, starting from P0, the baleen-bearing whales (Chaeomysticeti) represent the most frequent cetacean fossils (only a few mysticetes are known from the Chilcatay strata). Two chaeomysticete lineages are found in the Pisco Formation: Cetotheriidae (from Tiucetus rosae in P0 to Piscobalaena nana in P2) and Balaenopteroidea (from Pelocetus in P0 to several undescribed species of Balaenopteridae in P2, testifying to a progressive trend toward gigantism). Odontocetes are rare in P0, the “kentriodontid” Incacetus broggii being the only species described from these strata, but they become more abundant and diverse in P1 and P2. In P1, the commonest toothed whale is Messapicetus gregarius, a member of Ziphiidae featuring an extremely elongated rostrum and a complete set of functional teeth. Another ziphiid from P1 is Chimuziphius coloradensis, known only from the fragmentary holotype cranium. The P1 strata also record the appearance of the crown Delphinida, with the superfamily Inioidea being represented by two small pontoporiids (Brachydelphis mazeasi and Samaydelphis chacaltanae) and one iniid (Brujadelphis ankylorostris). Moreover, P1 is also home to the stem physeteroid Livyitan melvillei; featuring a three-m-long skull and teeth reaching 36 cm in length, L. melvillei was one of the largest raptorial predators and, possibly, the biggest tetrapod bite ever found. Acrophyseter is another macroraptorial sperm whale, distinctly smaller than L. melvillei, known from both P1 and P2. Even smaller in size are the kogiids Platyscaphokogia landinii and Scaphokogia cochlearis, both of which are known from the upper strata of P2. The same allomember is also home to the ziphiids Chavinziphius maxillocristatus and Nazcacetus urbinai, the “kentriodontids” Atocetus iquensis and Belenodelphis peruanus, and undescribed members of Phocoenidae
Neogene astropectinids of Italy and extant forms of the Mediterranean Sea: a preliminary reappraisal
No full textAstropectinidae represent the largest family of extant Asteroidea. Within this family, the genus Astropecten including more than two fifths of the total number of species. Although most astropectinids occur in cold waters, various species of Astropecten currently inhabit the Mediterranean Sea, namely: Astropecten aranciacus (Linnaeus, 1758); A. jonstoni (Delle Chiaje, 1827); A. irregularis (Pennant, 1777); A. spinulosus (Philippi, 1837); A. bispinosus (Otto, 1823), and A. platyacanthus (Philippi, 1837). These extant forms share several morphological characters with some fossil individuals referred to the same genus. Indeed, since the mid-XIX Century, several authors described complete astropectinids specimens from the Neogene marine sediment exposed in Central and Northern Italy. The earliest mentioned in literature is the holotype and only known specimen of Crenaster montalionis Meneghini 1852 from Montaione (FI). This specimen is currently subject of redescription and taxonomic re-evaluation by the authors of the present study. Cavara (1866) and Sacco (1893) illustrated A. bononiensis Cavara, 1866, A. cf. bispinosus Otto, 1823 and Astropecten sp. all from the Piacenzian outcrops of the Asti Province. Del Prato (1896) described the new species A. linati Del Prato, 1896 from the Mio-Pliocene deposits of the Parma Province as well as Astropecten sp. from the Langhian beds of Gombio (RE); this specimen was later referred by Borghi & Bajo Campos (2008) to Astropecten cf. forbesi Heller, 1858. Moreover, after a huge gap, Repetto & Bicchi (2013) described Astropecten cf. irregularis pentacanthus Delle Chiaje, 1825 from the muddy clay outcrops of Cherasco (AT)
Some considerations on the nomenclatural and taxonomic status of the upper Miocene ocean sunfish Orthagoriscus (Mola) lathanicus Gagnaison & Bouilly, 2009
No full textThe family Molidae comprises one of the tetraodontiform lineages with the least known fossil record. Each new addition to the short list of extinct molid taxa significantly contributes to shed light on the patterns of diversity and distribution of ocean sunfishes through time. This is particularly true for the Miocene, which is regarded as an interval of increased abundance and diversity of ocean sunfishes worldwide. Here, we reconsider the nomenclatural status of the fossil ocean sunfish taxon Orthagoriscus (Mola) lathanicus Gagnaison & Bouilly, 2009 from the upper Miocene of central-western France and argue that it represents an unavailable species name in light of the ICZN Code's criteria. In addition, we briefly discuss the taxonomic significance of the specimens that have been assigned to Orthagoriscus (Mola) lathanicus in the broader framework of the upper Miocene fossil record of the family Molidae from the Northeastern Atlantic region. We conclude that these fossils are too fragmentary to comprise the hypodigm of a new species, and should rather be regarded as not diagnostic below the family-level
Redescription and first illustration of the holotype of Astropecten montalionis (Meneghini, 1852) [Paxillosida: Astropectinidae]
Full text linkAstropecten montalionis (Echinodermata: Asteroidea: Astropectinidae) was first described by Giuseppe Meneghini in 1852 (as Crenaster montalionis), the description following the donation by the municipality of Montaione (Tuscany, Central Italy) of a sandstone slab with an embedded fossil starfish specimen to the Museo di Storia Naturale dell’Università di Pisa. This slab was previously embedded in the floor of the main square of Montaione, in front of the church of S. Regolo, and for a long time it was eroded and damaged by pedestrian passage. Unfortunately, the specimen has never been figured in the literature. This fossil is here redescribed, taxonomically re-evaluated, and figured
Cenozoic vertebrates from the central Mediterranean Basin: A tribute to the palaeontological legacy of Giovanni Capellini (1833-1922)
No full textA new record of Gunnellichnus moghraensis from the Middle Miocene of Belgium, with some remarks on the origin of this seemingly uncommon ichnospecies
No full textIn spite of the common and widespread occurrence of turtle shell remains in many fossil vertebrate assemblages worldwide, only a few palaeontological studies exist detailing the occurrence and significance of turtle bone modification features. Among the few ichnotaxa that have recently been described from fossil plastral and carapacial elements of both terrestrial and aquatic turtles, Gunnellichnus moghraensis is currently only known from the holotype and five associated specimens occurring on a single plastron of the freshwater turtle Erymnochelys from the Lower Miocene of Egypt. Here, we report on new examples of G. moghraensis occurring on a marine turtle costal plate from the lower Middle Miocene (ca. 15.97 to 14.8 Ma) strata of the Antwerpen Member of the Berchem Formation at Berchem, near Antwerp, in northern Belgium. A scrutiny of palaeontological literature reveals that similar traces also occur on carapacial elements of the Upper Cretaceous cheloniid Allopleuron hofmanni from the Maastrichtian type area. The hypothesis that G. moghraensis and the allied ichnospecies Gunnellichnus akolouthiste represent the product of bacterial and/or fungal degradation of the turtle shell is here preferred to alternative explanations that involve the joint action of sessile epibiotic macro-invertebrates
- …
