Paleobiology of firmground burrowers and cryptobionts at a Miocene omission surface, Alcoi, SE Spain

Abstract

A well-preserved omission surface (sedimentary discontinuity) in an outcrop near Alcoi in southeastern Spain displays trace fossils and body fossils that reflect a dynamic benthic community during the Miocene (Langhian–Tortonian). This outcrop, besides being the type locality of Spongeliomorpha iberica Saporta, 1887, exhibits other abundant trace fossils, such as Glossifungites saxicava Łomnicki, 1886 and Gastrochaenolites ornatus Kelly and Bromley, 1984. These trace fossils are restricted to a single stratigraphic horizon and constitute a typical firmground ichnoassemblage of the Glossifungites ichnofacies. The interiors of some of the Glossifungites and Spongeliomorpha burrows were occupied by encrusting balanomorph barnacles (Actinobalanus dolosus Darwin, 1854). This paper is the first report of cryptic barnacles colonizing the interior of open burrows that constitute a typical firmground ichnocoenose in the fossil record. Detailed ichnologic study demonstrates that the ichnospecies Glossifungites saxicava stands as a valid ichnotaxon and is not a synonym of the ichnogenus Rhizocorallium, as has been suggested by some previous workers.

Glossifungites gingrasi n. isp., a probable subaqueous insect domicile from the Cretaceous Ferron Sandstone, Utah

“…As noted by Uchman et al (2000), in the G. saxicava type area, the width of smaller specimens of G. saxicava is rather consistent across the axial length, whereas in larger forms, the trace widens distally. A similar disparity is present in G. saxicava specimens of Belaústegui et al (2016a). This covariation of size and shape is also observed in specimens of G. gingrasi n. isp.…”

“…More recently, Knaust (2013) concluded that there are only two valid ichnospecies of Rhizocorallium (R. jenense and R. commune Schmid, 1876), and following Fürsich (1974), included Glossifungites under Rhizocorallium, although the two papers are not in complete agreement on the classification with regards to the importance of spreite versus passive fill or ichnotaxobase hierarchy (ichnospecies versus ichnosubspecies and variety). More recently, Belaústegui et al (2016a) refuted that Glossifungites was a junior synonym of Rhizocorallium, King et al-Glossifungites gingrasi n. isp., a probable subaqueous insect domicile and reintroduced Glossifungites saxicava as a valid ichnospecies using examples from Spain that contained barnacle-colonized interiors to illustrate the importance of differentiating passive versus active fills and the presence/absence of spreite as ichnotaxobases for differentiating ichnogenera.…”

“…Here, we follow the most recent nomenclature (Belaústegui et al, 2016a) in referring tongue-shaped, passively filled specimens to the ichnogenus Glossifungites. Figures 4-7, 8.4-8.7 Holotype.-North Carolina Museum of Natural Sciences (Raleigh, North Carolina) specimen slab NCSM 12618 (45 x 37 cm) containing the holotype and at least 20 syntypes (Fig.…”

“…The distal portion of the trace fossil is usually wider than the apertural portion. The surface of the trace fossil is covered by bioglyphs (adapted from Łomnicki, 1886 and Belaústegui et al, 2016a).…”

Differences between autogenic and allogenic expressions of the Glossifungites Ichnofacies in estuarine and shoreface deposits from the Permian of the Paraná Basin, Brazil

“…Several ichnotaxa were registered in the Glossifungites Ichnofacies and characterize different feeding behaviours. The majority of this record include Conichnus , Skolithos , Diplocraterion , Arenicolites , Gastrochaenolites , and Bergaueria (suspension feeders), Thalassinoides, Glossifungites , and Psilonichnus (deposit‐feeders), Spongeliomorpha (deposit‐feeders or farming behaviour), and Palaeophycus (suspension feeders, deposit‐feeders or carnivores) (e.g., Abdel‐Fattah, Gingras, Caldwell, Pemberton, & MacEachern, 2016; Balistieri & Netto, 2002; Belaústegui, Ekdale, Domènech, & Martinell, 2016; Bromley & Allouc, 1992; Buatois & Encinas, 2006; Buatois, Mángano, Alissa, & Carr, 2002; Carmona, Ponce, Mángano, & Buatois, 2006; Dasgupta & Buatois, 2012; Fielding, Bann, MacEachern, Tye, & Jones, 2006; Gandini, Netto, Kern, & Lavina, 2010; Netto et al, 2007; Pearson, Mángano, Buatois, Casadío, & Raising, 2012; Pemberton & Frey, 1985; Savrda, 1991; Schultz, Furlong, & Zonneveld, 2016; Sedorko, Netto, & Savrda, 2018; Seilacher, 1967). However, burrows such as Planolites , Taenidium , Rhizocorallium , Zoophycos (deposit‐feeders), and Chondrites (chemichnion) were also attributed to trace fossil suites of the Glossifungites Ichnofacies (Cónsole‐Gonella, Griffin, & Aceñolaza, 2009; MacEachern & Burton, 2000; Uchman, Bubniak, & Bubniak, 2000), a matter that still needs review.…”