Identification of fossil worm tubes from Phanerozoic hydrothermal vents and cold seeps Author Georgieva, Magdalena N. Department of Life Sciences, Natural History Museum, London, United Kingdom; & School of Earth and Environment, University of Leeds, Leeds, United Kingdom; Author Little, Crispin T. S. School of Earth and Environment, University of Leeds, Leeds, United Kingdom; Author Watson, Jonathan S. Department of Earth Science and Engineering, Imperial College London, London, United Kingdom; Author Sephton, Mark A. Department of Earth Science and Engineering, Imperial College London, London, United Kingdom; Author Ball, Alexander D. Core Research Laboratories, Natural History Museum, London, United Kingdom Author Glover, Adrian G. Department of Life Sciences, Natural History Museum, London, United Kingdom; text Journal of Systematic Palaeontology 2019 2017-12-28 17 4 287 329 http://dx.doi.org/10.1080/14772019.2017.1412362 journal article 10.1080/14772019.2017.1412362 1478-0941 10883381 ?Family Siboglinidae Caullery, 1914 ‘Murdock Creek tubes’ ( Fig. 5 ) Material. WA-MC LACMIP loc. 6295, one spiralling tube ( Fig. 5A ), another tube with a ~ 90 º bend, and a smaller tube observed in thin section only. Donated by J. L. Goedert. Occurrence. Murdock Creek, Clallam County, Washington State , USA ( ~ 48 º 9 ' N, 123 º 52 ' W). Loose seep carbonate blocks. Pysht Formation, late Early Oligocene ( Goedert & Squires 1993 ; Kiel & Amano 2013 ; Vinn et al. 2013 ). Description. Carbonate tubes 0.7–3.0 mm in diameter, appearing non-branched, non-agglutinated and nontapering in the tube fragments observed. The spiralling tube ( Fig. 5A ) appears to have coarse longitudinal wrinkles on its surface, but whether these are original is uncertain. In thin section, tube walls are thick and concentrically multi-layered ( Fig. 5B–D ), and occasionally delaminated ( Fig. 5B ). Some of the tubes appear to have originally been flexible ( Fig. 5C ) and to have had fibrous walls due to visible preserved wall tears in thin section ( Fig. 5D ). Remarks. These tubes appear to have been organic originally due to preserved tube wall tears that reveal a fibrous nature. The size of the tubes, their thick, multi-layered walls and the spiralling that they exhibit suggest that the tubes may have been made by vestimentiferans, as the combination of these features are not commonly encountered in other organic tube-building annelids that occur at vents and seeps. Due to a limited amount of material available for study, and as these tubes were only resolved among those of siboglinids when homoplastic characters are downweighted less within cladistic analyses ( Fig. 23B ), the tubes are only tentatively assigned to the siboglinids.