The Burgess Shale

Creatures: Filterers

Nereocaris exilis

Nereocaris briggsi, holotype ROMIP 62153

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Hymenocarines, Family: Odaraiidae
Species name: Nereocaris exilis
Remarks:

Hymenocarines were early arthropods with bivalved carapaces and mandibles, forming the bulk of the first mandibulates (represented today by myriapods, crustaceans and insects) (Aria and Caron 2017; Vannier et al. 2018). In many hymenocarines, including Nereocaris, determining the exact number and types of appendages in their head remains difficult, which hinders a detailed understanding of the evolutionary relationships inside this group. Nereocaris most probably belongs to the family Odaraiidae, a group of hymenocarines with highly multisegmented bodies, reduced or absent antennae and highly multisegmented legs.

Described by: Legg, D. A., Sutton, M. D., Edgecombe, G. D., Caron, J-B.
Description date: 2012
Etymology:

Nereocaris – After “Nereus”, the Greek titan with a fish-like tail and the Latin caris, meaning “crab” or “shrimp”, and

exilis – from the Latin exilis, meaning “slender”.

Type Specimens: dsfsdfdsfdsfdasf
Other species:

Holotype ROMIP61831

Age & Localities:

Age:
Middle Cambrian, Wuliuan Stage, Burgess Shale Formation (around 507 million years old)
Principal localities:

Tulip Beds (S7) (N. exilis) and the Collins Quarry (N. briggsi).

History of Research:

Brief history of research:

The first description of Nereocaris exilis was published in 2012 based on specimens from the Tulip Beds site in Mount Stephen (Yoho National Park). Two years later, Nereocaris briggsi was described based on specimens from the Collins Quarry in Mount Stephen (Legg and Caron 2014). Nereocaris was originally described with a median eye protruding from a single eye peduncle located between the lateral eyes (Legg et al. 2012; Legg and Caron 2014). This structure was later reinterpreted as one of a pair of frontal filaments; short unsegmented limb-like structures with a sensorial function (Izquierdo-López and Caron 2022). Similarly, the tail fan of Nereocaris exilis was initially interpreted as having six pairs of lateral caudal rami (termed telson processes in the original study) and one medial telson process. This structure was later reinterpreted as two pairs of three-partite caudal rami borne by the terminal segment (“te” in Izquierdo-López and Caron, 2022), and was also reconstructed as such for N. briggsi (Izquierdo-López and Caron 2022). The discovery of Nereocaris and the phylogenetic analyses adjunct to the publication have been key to the interpretation of hymenocarines as earliest euarthropods (Legg et al. 2013; Fu et al. 2022) (or ‘upper stem-euarthropods’ based on Ortega-Hernández 2014). The discovery of mandibles in several hymenocarines (Aria and Caron 2017; Vannier et al. 2018; Zhai et al. 2019) has prompted the reinterpretation of this group as mandibulates, although the mandibulates affinities of Nereocaris and other odaraiids remain unclear pending clearer resolution of their head appendages.

Description:

Morphology:

The carapace of Nereocaris has a dome-like shape, compressed laterally, which becomes progressively wider towards the back of the animal. The top of the carapace bears a dorsal crest (keel) that runs across its entire length and extends posteriorly into a small process. The carapace is truncated anteriorly, and each valve extends towards the ventral side, terminating into an anterior hook. The carapace valves extend beyond the length of the legs, and in N. briggsi extend across the ventral side, similar to Odaraia alata. The head bears one pair of short pedunculate eyes and one pair of thin and small, unsegmented appendages (frontal filaments). Antennulae appear to be absent, and further cephalic specializations are unknown from the material available. The body of Nereocaris is highly multisegmented, reaching more than 90 segments in N. exilis. The trunk is subdivided into a thoracic region with limbs and a long limbless abdomen. Limbs are short, subdivided into two branches (biramous): a walking leg (endopod) and a seemingly paddle-like flap (exopod). Based on N. briggsi, the walking legs are probably subdivided into 14 or similar segments (podomeres). The exact morphology and size of the exopods is not well-preserved, but darker areas close to the legs’ base could indicate their approximate shape and length. The terminal segment is distinctly larger than the preceding segments and extends into a blunt process towards the posterior side of the animal (the “mtp” in Legg & Caron, 2014). This last segment bears one pair of caudal rami, each being partly subdivided into three smaller segments (tripartite). Each segment bears one spine on its outer edge.

Abundance:

Nereocaris exilis is rare, only known from three specimens from the same locality. Nereocaris briggsi is highly abundant in its locality, with over 190 specimens known.

Maximum Size:
About 14.2 cm (N. exilis)

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

The limbs of Nereocaris exilis do not extend beyond the carapace ventral margin, indicating that they were not used for crawling. By contrast, the limbs of Nereocaris briggsi protrude from the carapace, but these were considered ill-suited to walk on the benthos (Legg and Caron 2014). For this reason, Nereocaris was reconstructed as a nektonic species, using its long abdomen as a means of propulsion (Legg et al. 2012; Perrier et al. 2015). N. exilis could have been a suspension-feeder, based on the lack of any raptorial or similar predatory limbs, but this possibility was questioned based on the lack of endites or setae on the limbs (Legg et al. 2012), which are widely used by extant filter-feeding crustaceans (Riisgård and Larsen 2010). A straight gut in N. briggsi, a simple tube filled with sediment may support the presence of a suspension or deposit feeding lifestyle, in which the animal would have consumed mud containing organic material (Legg and Caron 2014). It was also hypothesized that multiple odaraiids (Izquierdo-López and Caron 2022), most prominently Fibulacaris (Izquierdo-López and Caron 2019), could have swum upside-down, thus facilitating the capture of particles by the carapace. Whether Nereocaris could have adopted such behaviour remains uncertain.

References:

  • ARIA, C. and CARON, J. B. 2017. Burgess Shale fossils illustrate the origin of the mandibulate body plan. Nature, 545: 89–92.
  • FU, D., LEGG, D. A., DALEY, A. C., BUDD, G. E., WU, Y. and ZHANG, X. 2022. The evolution of biramous appendages revealed by a carapace-bearing Cambrian arthropod. Philosophical Transactions of the Royal Society of London B, 377.
  • IZQUIERDO-LÓPEZ, A. and CARON, J. B. 2019. A possible case of inverted lifestyle in a new bivalved arthropod from the Burgess Shale. Royal Society Open Science, 6: 191350.
  • IZQUIERDO-LÓPEZ, A. and CARON, J.-B. 2022. Extreme multisegmentation in a giant bivalved arthropod from the Cambrian Burgess Shale. IScience, 25, 104675.
  • LEGG, D., SUTTON, M. D. and EDGECOMBE, G. D. 2013. Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature Communications, 4: 1–7.
  • LEGG, D. A. and CARON, J. B. 2014. New Middle Cambrian bivalved arthropods from the Burgess Shale (British Columbia, Canada). Palaeontology, 57: 691–711.
  • LEGG, D. A., SUTTON, M. D., EDGECOMBE, G. D. and CARON, J. B. 2012. Cambrian bivalved arthropod reveals origin of arthrodization. Proceedings of the Royal Society B: Biological Sciences, 279: 4699–4704.
  • ORTEGA-HERNÁNDEZ, J. 2014. Making sense of ‘lower’ and ‘upper’ stem-group Euarthropoda, with comments on the strict use of the name Arthropoda von Siebold, 1848. Biological Reviews, 91: 255–273.
  • PERRIER, V., WILLIAMS, M. and SIVETER, D. J. 2015. The fossil record and palaeoenvironmental significance of marine arthropod zooplankton. Earth-Science Reviews, 146: 146–162.
  • RIISGÅRD, H. U. and LARSEN, P. S. 2010. Particle capture mechanisms in suspension-feeding invertebrates. Marine Ecology Progress Series, 418: 255–293.
  • VANNIER, J., ARIA, C., TAYLOR, R. S. and CARON, J. B. 2018. Waptia fieldensis Walcott, a mandibulate arthropod from the middle Cambrian Burgess Shale. Royal Society Open Science, 5:172206.
  • ZHAI, D., ORTEGA-HERNÁNDEZ, J., WOLFE, J. M., HOU, X.-G., CAO, C. and LIU, Y. 2019. Three-dimensionally preserved appendages in an early Cambrian stem-group pancrustacean. Current Biology, 29: 171–177.
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Gyaltsenglossus senis

Gyaltsenglossus senis, holotype, ROMIP 65606.1

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: No subphylum assignment
Species name: Gyaltsenglossus senis
Remarks:

Gyaltsenglossus is currently considered a stem-group hemichordate. It has features of both the modern hemichordate groups in that it has the long proboscis and worm-shaped body of the Enteropneusta (acorn worms) and the crown of feeding tentacles of the Pterobranchia.

Described by: Nanglu et al. 2020
Description date: 2020
Etymology:

Gyaltsen (pronounced “GEN-zay”) in honour of the lead author’s father, and glossus from the Greek glossa, meaning tongue, a common generic suffix for hemichordates.

Senis from the Latin senex, meaning old.

Type Specimens: Holotype ROMIP 65606.1
Other species:

Burgess Shale and vicinity: None.
Other deposits: None

Age & Localities:

Age:
Middle Cambrian, Wuliuan Stage, upper part of the Burgess Shale Formation (around 507 million years old).
Principal localities:

Odaray Mountain, Yoho National Park.

History of Research:

Brief history of research:

Gyaltsenglossus was described in 2020 based on 33 specimens, all collected from Odaray Mountain. Only the holotype preserves all major anatomical features.

Description:

Morphology:

: Gyaltsenglossus is a worm roughly 2 cm long. At the anterior end, it has an elongate, ovoid, muscular proboscis. Behind the proboscis is a set of six arms which bore roughly 15 pairs of tentacles. These arms were roughly 1.5 times as long as the proboscis, based on measurements taken from the holotype. The tentacles give the arms an overall fuzzy or foliose appearance. Behind the feeding arms is a roughly cylindrical trunk, which tapers from the largest point at the anterior and becomes smaller towards the posterior end of the animal. On the dorsal side of the trunk, directly behind the feeding arms, an elevated area leads to a set of thin, thread-like appendages. Posterior to the trunk is a bulbous structure with internal features preserved more darkly than in the surrounding tissues. This bulbous structure may constitute thickened tissue. In some specimens, a gut ending prior to the posterior bulbous structure is preserved.

Abundance:

33 specimens were described.

Maximum Size:
About 2 cm.

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

The morphology of Gyaltsenglossus suggests that it had a two-part feeding ecology. The long proboscis could have been used to feed directly from the marine mud on which the animal would have lived, in a manner similar to that of modern-day acorn worms. The feeding arms could also have been used to filter food particles from the water above the organism, as done by pterobranchs. The posterior bulbous appendage may have been used to anchor Gyaltsenglossus to the seafloor, particularly when it was feeding on small particles from the water.

References:

  • NANGLU, K., J.-B. CARON, AND C. B. CAMERON. 2020. Cambrian tentaculate worms and the origin of the hemichordate body plan. Current Biology. 30 (21): 4238-4244
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Collinsovermis monstruosus

Collinsovermis monstruosus, holotype ROMIP 52703

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Order Luolishaniida, Family Collinsovermidae
Species name: Collinsovermis monstruosus
Remarks:

Collinsovermis is one of a variety of lobopodian taxa from the Cambrian, which are early members of the lineage that gave rise to arthropods, and whose only modern survivors are onychophorans (velvet worms) and tardigrades (water bears). Lobopodians characteristically have annulated, unjointed bodies and bear soft limbs after which they are called: the lobopods. Collinsovermis is an armoured member of the Order Luolishaniida, along with forms such as Collinsium and Luolishania from China, or Acinocricus from Utah—together forming the family Collinsovermidae. Luolishaniids are characterized by their thin spines arranged in chevrons and the differentiation of their body into functional regions for suspension-feeding (Caron & Aria 2017, 2020).

Described by: Caron and Aria
Description date: 2020
Etymology:

Collinsovermis – Collins, patronymic, honours its discoverer, Desmond Collins, and vermis is Latin for worm.

monstruosus – From the Latin, in reference to the nickname ‘Collins’ monster’, first introduced by Delle Cave & Simonetta (1991).

Type Specimens: Holotype: ROMIP 52703, Paratypes: ROMIP 52704 and 52705 at the Royal Ontario Museum, Toronto, Canada.
Other species:

Burgess Shale and vicinity: None.
Other deposits: None.

Age & Localities:

Age:
Middle Cambrian, Wuliuan stage, Bathyuriscus-Elrathina Zone of the Burgess Shale Formation (approximately 507 million years old).
Principal localities:

Mount Stephen

History of Research:

Brief history of research:

Collected by a Royal Ontario Museum expedition on Mount Stephen in 1983, the Collinsovermis animal was first revealed, unnamed and undescribed, in the non-peer-reviewed magazine Rotunda (former name of the Royal Ontario Museum Magazine), as a single picture of the holotype, with the caption: “What is it? This new spiny animal (4 cm) with hairy legs has a body plan that has not been seen before.” In 1991, Italian scientists Delle Cave and Simonetta (1991) provided a brief description of the taxon and attempted a reconstruction solely based on the photograph provided by Collins in the Rotunda magazine, coining it the “Collins’ monster”. Despite the lack of name and good documentation, the Collins’ monster have repeatedly featured in studies tackling lobopodian evolution and phylogeny (e.g., Ramsköld & Chen 1998; Budd 2001; Ou et al. 2011; Caron & Aria 2017). It was only in 2020 that the animal was formally named Collinsovermis monstruosus, in honour of Desmond Collins, and fully described based on high resolution pictures of all available material (Caron & Aria 2020).

Description:

Morphology:

Collinsovermis has a plump appearance, with an annulated, unjointed body divided into anterior and posterior regions. The entire dorsum of the body is covered in well-developed spines—three short pairs cover the first three somites (“body segments”) behind the head, while triads of longs spines cover the remaining 10 somites. The anterior region bears 6 pairs of elongate lobopods with thin spines arranged in chevrons, and a small head, as a protrusion bearing a pair of sensory filaments as well as a small dorsal plate and a frontal mouth. The posterior region is made ventrally of 8 pairs of stout annulated lobopods ending in strong, single claws.

Abundance:

Like other lobopodians, Collinsovermis is excessively rare. There are only 3 specimens known, all from the Collins Quarry on Mount Stephen (Fletcher & Collins 2003). They are housed at the Royal Ontario Museum, Department of Natural History.

Maximum Size:
32 mm.

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Collinsovermis exemplifies suspension-feeding adaptations in lobopodians associated with strongly-developed defensive elements. Like other members of the order Luolishaniidae, and those of the family bearing its name, this animal was using its stout back limbs for anchoring (probably to sponges) and its slender spinose anterior limbs to sieve organic particles or plankton. The long dorsal spines most certainly served as deterrent to predators.

References:

  • BUDD, G. E. 2001. Tardigrades as ‘stem-group arthropods’: The evidence from the Cambrian fauna. Zoologischer Anzeiger, 240, 265–279.
  • CARON, J. and ARIA, C. 2020. The Collins’ monster, a spinous suspension‐feeding lobopodian from the Cambrian Burgess Shale of British Columbia. Palaeontology, 63, 979–994.
  • CARON, J.-B. and ARIA, C. 2017. Cambrian suspension-feeding lobopodians and the early radiation of panarthropods. BMC Evolutionary Biology, 17, 29.
  • DELLE CAVE, L. and SIMONETTA, A. M. 1991. Early Palaeozoic arthropods and problems of arthropod phylogeny; with some notes on taxa of doubtful affinities. In S, S. A. M. C. M. (ed.) The Early Evolution of Metazoa and the Significance of Problematic Taxa. Proceedings of an International Symposium Held at the University of Camerino 27-31 March 1989, Cambridge University Press, 189–244 pp.
  • FLETCHER, T. P. and COLLINS, D. 2003. The Burgess Shale and associated Cambrian formations west of the Fossil Gully Fault Zone on Mount Stephen, British Columbia. Canadian Journal of Earth Sciences, 40, 1823–1838.
  • OU, Q., LIU, J., SHU, D., HAN, J., ZHANG, Z., WAN, X. and LEI, Q. 2011. A rare onychophoran-like lobopodian from the lower Cambrian Chengjiang Lagerstätte. Journal of Paleontology, 85, 587–594.
  • RAMSKÖLD, L. and CHEN, J. Y. 1998. Cambrian lobopodians: morphology and phylogeny. In EDGECOMBE, G. D. (ed.) Arthropod Fossils and Phylogeny, Columbia University Press, New York, 107–150 pp.
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Vauxia gracilenta

3D animation of Vauxia bellula and other sponges (Choia ridleyi, Diagoniella cyathiformis, Eiffelia globosa, Hazelia conferta, Pirania muricata, and Wapkia elongata) and Chancelloria eros a sponge-like form covered of star-shaped spines.

ANIMATION BY PHLESCH BUBBLE © ROYAL ONTARIO MUSEUM

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Demospongea (Order: Verongida)
Species name: Vauxia gracilenta
Remarks:

Vauxia was placed within the hexactinellids by Walcott in his 1920 original description but Rigby (1980) transferred the genus and family to the Demospongea. Demosponges, the same group that are harvested as bath sponges, represent the largest class of sponges today.

Described by: Walcott
Description date: 1920
Etymology:

Vauxia – from Mount Vaux (3,319 m), a mountain Peak in Yoho National Park, British Columbia. The name refers to William Sandys Wright Vaux (1818-1885) an antiquarian at the British Museum.

gracilenta – from the Latin gracilis, “slender,” referring to the delicate structure of the sponge.

Type Specimens: Lectotypes –USNM66515 (V. gracilenta),USNM66508 (V. bellula),USNM66517 (V. densa),USNM66520 (V. venata), in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA. Holotype –ROM53572 (V. irregulara) in the Royal Ontario Museum, Toronto, Canada.
Other species:

Burgess Shale and vicinity: V. bellula Walcott, 1920; V. densa Walcott, 1920; V. irregulara Rigby and Collins, 2004; V. venata Walcott, 1920.

Other deposits: none.

Age & Localities:

Age:
Middle Cambrian, Bathyuriscus-Elrathina Zone (approximately 505 million years ago).
Principal localities:

Burgess Shale and vicinity: Vauxia species are known in the Walcott, Raymond and Collins Quarries on Fossil Ridge, the Trilobite Beds, Tulip Beds (S7) and the Collins Quarry on Mount Stephen, and smaller sites on Mount Field and Odaray Mountain. Vauxia is also known from Monarch in Kootenay National Park.

Other deposits: V. bellula Walcott, 1920 from the Middle Cambrian Wheeler and Marjum Formations in Utah (Rigby et al., 2010); V. magna Rigby, 1980 from the Middle Cambrian Spence Shale in Utah (Rigby, 1980).

History of Research:

Brief history of research:

This sponge was originally described by Walcott in 1920. The genus was reviewed by Rigby (1980) and the species redescribed by Rigby (1986) and Rigby and Collins (2004) in their examination of the Burgess Shale sponges.

Description:

Morphology:

Specimens of Vauxia gracilenta can range from simple unbranched forms to more complex branching forms and reach up to 8 cm in height. Each branch is deeply conical and almost cylindrical, with a simple open central cavity (spongocoel) ending in a rounded of flat opening (osculum). The skeleton is double layered with a thin dermal layer and an inner layer (endosomal). The dermal layer has small openings (ostia) and is composed of a dense network of ladder-like fibers supported by radial fibers from the inner layer. The inner layer forms a regular reticulated net-like skeleton of fibers with 4-6 sided polygons which is characteristic of the genus and species. The fibrous elements (spongin) represent tough collagen proteins. There is no evidence of siliceous spicules in the skeleton.

The different species have been identified mostly based on variations of the skeletal elements and the shape of the branches. Some species can reach up to at least 15 cm in height (V. bellula, V. densa).

Abundance:

Vauxia is relatively common in the Raymond Quarry and other sites on Mount Stephen but is rare in the Walcott Quarry where it represents less than 0.05% of the community (Caron and Jackson, 2008).

Maximum Size:
80 mm

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Vauxia would have lived attached to the sea floor. Particles of organic matter were extracted from the water as they passed through canals in the sponge’s wall.

References:

CARON, J.-B. AND D. A. JACKSON. 2008. Paleoecology of the Greater Phyllopod Bed community, Burgess Shale. Palaeogeography, Palaeoclimatology, Palaeoecology, 258: 222-256.

RIGBY, J. K. 1980. The new Middle Cambrian sponge Vauxia magna from the Spence Shale of Northern Utah and taxonomic position of the Vauxiidae. Journal of Paleontology, 54(1): 234-240.

RIGBY, J. K. 1986. Sponges of the Burgess Shale (Middle Cambrian), British Columbia. Palaeontographica Canadiana, 2: 1-105 p.

RIGBY, J. K. AND D. COLLINS. 2004. Sponges of the Middle Cambrian Burgess Shale and Stephen Formations, British Columbia. Royal Ontario Museum Contributions in Science (1): 155 p.

RIGBY, J. K., S. B. CHURCH AND N. K. ANDERSON. 2010. Middle Cambrian Sponges from the Drum Mountains and House Range in Western Utah. Journal of Paleontology, 84: 66-78.

WALCOTT, C. D. 1920. Middle Cambrian Spongiae. Cambrian Geology and Paleontology IV. Smithsonian Miscellaneous Collections, 67(6): 261-365.

Other Links:

None

Pirania muricata

3D animation of Pirania muricata and other sponges (Choia ridleyi, Diagoniella cyathiformis, Eiffelia globosa, Hazelia conferta, Vauxia bellula, and Wapkia elongata) and Chancelloria eros a sponge-like form covered of star-shaped spines.

ANIMATION BY PHLESCH BUBBLE © ROYAL ONTARIO MUSEUM

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Demospongea (Order: Monaxonida)
Species name: Pirania muricata
Remarks:

Pirania is considered a primitive demosponge (Rigby, 1986). Demosponges, the same group that are harvested as bath sponges, represent the largest class of sponges today.

Described by: Walcott
Description date: 1920
Etymology:

Pirania – from Mount Saint Piran (2,649 m), situated in the Bow River Valley in Banff National Park, Alberta. Samuel Allen named Mount St. Piran after the Patron Saint of Cornwall in 1894.

muricata – from the Latin muricatus, “pointed, or full of sharp points.” The name refers to the large pointed spicules extending out from the wall of the sponge.

Type Specimens: Lectotype –USNM66495 (erroneously referred as 66496 in Rigby, 1986), in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Other species:

Burgess Shale and vicinity: none

Other deposits: Pirania auraeum Botting, 2007 from the Lower Ordovician of Morocco (Botting, 2007); Pirania llanfawrensis Botting, 2004 from the Upper Ordovician of England (Botting, 2004).

Age & Localities:

Age:
Middle Cambrian, Bathyuriscus-Elrathina Zone (approximately 505 million years ago).
Principal localities:

The Walcott Quarry on Fossil Ridge. The Trilobite Beds and Tulip Beds (S7) on Mount Stephen and several smaller sites on Mount Field, Mount Stephen and Mount Odaray.

History of Research:

Brief history of research:

Pirania was first described by Walcott (1920). Rigby (1986) redescribed this sponge and concluded that the skeleton is composed of hexagonally arranged canals, large pointed spicules and tufts of small spicules. This sponge was also reviewed by Rigby and Collins based on new material collected by the Royal Ontario Museum (2004).

Description:

Morphology:

Pirania is a thick-walled cylindrical sponge that can have up to four branches. The skeleton of the sponge is composed of tufts of small spicules and has very distinctive long pointed spicules that emerge from the external wall. Long canals perforate the wall of the sponge to allow water flow through it. Branching occurs close to the base of the sponge.

Abundance:

Pirania is common in most Burgess Shale sites but comprises only 0.38% of the Walcott Quarry community (Caron and Jackson, 2008).

Maximum Size:
30 mm

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Pirania would have lived attached to the sea floor. Particles of organic matter were extracted from the water as they passed through canals in the sponge’s wall. The brachiopods Nisusia and Micromitra a range of other sponges and even juvenile chancelloriids are often found attached to the long spicules of this sponge, possibly to avoid higher turbidity levels near the seafloor.

References:

BOTTING, J. P. 2004. An exceptional Caradoc sponge fauna from the Llanfawr Quarries, Central Wales and phylogenetic implications. Journal of Systematic Paleontology, 2: 31-63.

BOTTING, J. P. 2007. ‘Cambrian’ demosponges in the Ordovician of Morocco: insights into the early evolutionary history of sponges. Geobios, 40: 737-748.

CARON, J.-B. AND D. A. JACKSON. 2008. Paleoecology of the Greater Phyllopod Bed community, Burgess Shale. Palaeogeography, Palaeoclimatology, Palaeoecology, 258: 222-256.

RIGBY, J. K. 1986. Sponges of the Burgess shale (Middle Cambrian), British Columbia. Palaeontographica canadiana, 2: 105 p.

RIGBY, J. K. AND D. COLLINS. 2004. Sponges of the Middle Cambrian Burgess Shale and Stephen Formations, British Columbia. Royal Ontario Museum Contributions in Science (1): 155 p.

WALCOTT, C. D. 1920. Middle Cambrian Spongiae. Cambrian Geology and Paleontology IV. Smithsonian Miscellaneous Collections, 67(6): 261-365.

Other Links:

None

Paterina zenobia

3D animation of Paterina zenobia and other brachiopods (Acrothyra gregaria, Diraphora bellicostata, Micromitra burgessensis, and Nisusia burgessensis).

ANIMATION BY PHLESCH BUBBLE © ROYAL ONTARIO MUSEUM

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Paterinata (Order: Paterinida)
Species name: Paterina zenobia
Remarks:

A brachiopod within the family Paterinidae.

Described by: Walcott
Description date: 1912
Etymology:

Paterina – from the Latin word pater, “father,” because the species was considered the ancestor of modern brachiopods, and the diminutive suffix, – ina, “derived from.”

zenobia – possibly from the Greek, Zeon, a form of Zeus.

Type Specimens: Syntype–USNM58311; plesiotypesUSNM56907, 51483, 69631- 69637 in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Other species:

Burgess Shale and vicinity: None to date. The Burgess Shale brachiopods, in particular from the Trilobite Beds on Mount Stephen, need to be re-examined (see also Brief history of research).

Other deposits: Several species are known in the Lower to the Middle Cambrian worldwide.

Age & Localities:

Age:
Middle Cambrian, Glossopleura Zone and Bathyuriscus-Elrathina Zone (approximately 505 million years ago).
Principal localities:

The Walcott Quarry on Fossil Ridge and the Trilobite Beds on Mount Stephen.

History of Research:

Brief history of research:

Walcott originally assigned specimens collected from the Burgess Shale and Mount Stephen to Micromitra zenobia Walcott (1912) and a subspecies of Paterina stissingensis, called Paterina stissingensis ora Walcott (1912). Both taxa were redescribed as Paterina zenobia by Resser (1938), a combination still in use today. However, close similarities between species of the two genera have created difficulties in defining their specific characteristics, which have resulted in many incorrectly identified specimens.

Description:

Morphology:

Paterina is the type genus of one of the earliest and most primitive brachiopod groups, the Paterinata. Unlike many modern brachiopods, its hinge line is straight and crosses almost the full width of the shell. The moderately biconvex shell grows consistently, rather than showing separate stages of development. Its exterior growth lines are coarse and regular. Faint radial ridges are present at the apex of some adult specimens. No preserved soft parts are known and the shell was originally mineralized.

Abundance:

This species is rare in the Walcott Quarry and represents a very small fraction of the entire fauna (<0.05%) (Caron and Jackson, 2008).

Maximum Size:
11 mm

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Paterina probably attached to the substrate by a very short stalk. Paterina extracted food particles from the water with its filter-feeding apparatus (located between the shells) called a lophophore.

References:

CARON, J.-B. AND D. A. JACKSON. 2008. Paleoecology of the Greater Phyllopod Bed community, Burgess Shale. Palaeogeography, Palaeoclimatology, Palaeoecology, 258: 222-256.

RESSER, C. E. 1938. Fourth contribution to nomenclature of Cambrian Fossils. Smithsonian Miscellaneous Collections, 97: 1-43.

WALCOTT, C. D. 1912. Cambrian Brachiopoda. United States Geological Survey, Monograph, 51: part I, 812 p; part II, 363 p.

Other Links:

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Oesia disjuncta

Oesia disjuncta (USNM 57630) – Lectotype, part and counterpart. Complete specimen. Specimen length = 85 mm. Specimen wet – direct light (top row), wet – polarized light (bottom row). Walcott Quarry.

© SMITHSONIAN INSTITUTION – NATIONAL MUSEUM OF NATURAL HISTORY. PHOTO: JEAN-BERNARD CARON

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Enteropneusta
Species name: Oesia disjuncta
Remarks:

Oesia is considered a stem-group enteropneust (acorn worms) and has the characteristic three-part anatomy of the group, consisting of a proboscis, collar and trunk (Nanglu et al. 2016; Nanglu et al. 2020).

Described by: Walcott
Description date: 1911
Etymology:

Oesia — from Lake Oesa, a small lake located a few kilometres southeast of the Burgess Shale.

disjuncta — from the Latin prefix dis, to signify a negation, and junctus, “joined.” The name is probably in reference to the crooked or bent shape of the early discovered specimens of Oesia.

Type Specimens: Lectotype –USNM57630 in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Other species:

Burgess Shale and vicinity: none.

Other deposits: none.

Age & Localities:

Age:
Middle Cambrian, Wuliuan stage, Burgess Shale Formation (around 507 million years old).
Principal localities:

Marble Canyon (Kootenay National Park), the Walcott Quarry on Fossil Ridge.

History of Research:

Brief history of research:

Walcott (1911) described this species as a polychaete worm, but this view was challenged by Lohman (1920) who suggested a tunicate (chordate) affinity instead. Conway Morris (1979) rejected both interpretations, and this animal was later regarded as a problematic organism of unknown affinity (Briggs and Conway Morris, 1986). Szaniawski suggested a chaetognath affinity in 2005, which was argued against by Conway Morris in 2009. Nanglu et al. formally redescribed Oesia as an enteropneust (hemichordate) in 2016.

Description:

Morphology:

Oesia ranged in length from 2.4mm – 120mm, with an average length of 53mm. The anteriormost region is an oval or “acorn” shaped proboscis, which gives the acorn worms (Enteropneusta) their common name. The proboscis is frequently preserved with a darker, more dense carbon content than surrounding tissues, suggesting that it was highly muscular as the proboscis is in modern acorn worms. Behind the proboscis was a short cylindrical region called the collar, which enclosed the mouth. Behind the collar was a long, cylindrical region called the trunk, which maintain a roughly even width throughout. Unlike in modern acorn worms or its contemporary Spartobranchus, the trunk of Oesia was not divided into a pharynx and a posterior trunk. Instead, the collagenous gill bars that define the pharynx continue throughout the entire length. This gives Oesia a relatively inflexible appearance. At the posterior end of Oesia was a bilobed shaped attachment structure. The interior of this structure also preserved highly concentrated carbon relative to surrounding tissue which, along with its shape, suggests that this appendage was for grasping. Oesia is often found inside another fossil previously described as the alga Margaretia dorus, but which is now recognized as the secreted dwelling of Oesia, which was likely used for feeding as a pre-filtration device. This tube was typically twice the width of Oesia and could reach nearly 50 cm in total length. The tube contained a series of spirally arranged pores and could bifurcate into branches as many as 5 or 6 times (although 1 or 2 bifurcations is more common).

Abundance:

Oesia is relatively rare at the Walcott Quarry, but is abundant at Marble Canyon where it represents the third most abundant species with 3,373 specimens (Nanglu et al. 2020).

Maximum Size:
120 mm.

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Oesia was likely a suspension feeder, owing to its extended pharynx laden will gill bars. These gill bars would have been covered in small hair-like structures called cilia which would move to create a flow of water towards the mouth and into the body. Excess water would then be expelled through pores, while food was passed through the gut. The large tubes of Oesia would have projected from the muddy seafloor into the water, with the pores allowing for water to move in and out of the tube. This would allow for fresh water for Oesia to feed on and refresh the tube with oxygenated water.

References:

 

  • BRIGGS, D. E. G. AND S. CONWAY MORRIS. 1986. Problematica from the Middle Cambrian Burgess Shale of British Columbia, p. 167-183. In A. Hoffman and M. H. Nitecki (eds.), Problematic fossil taxa (Oxford Monographs on Geology and Geophysics No. 5). Oxford University Press & Clarendon Press, New York.
  • CONWAY MORRIS, S. 1979. The Burgess Shale (Middle Cambrian) fauna. Annual Review of Ecology and Systematics, 10(1): 327-349.
  • CONWAY MORRIS, S. 2009. The Burgess Shale animal Oesia is not a chaetognath: A reply to Szaniawski (2005). Acta Palaeontologica Polonica, 54(1): 175-179.
  • LOHMANN, H. 1920. Oesia disjuncta Walcott, eine Appendicularie aus dem Kambrium. Mitteilungen aus dem Zoologischen Staatsinstitut und Zoologischen Museum in Hamburg, 38: 69-75.
  • NANGLU, K., CARON, J.-B., CONWAY MORRIS, S.C., AND C. B. CAMERON. 2016. Cambrian suspension-feeding tubicolous hemichordates. BMC Biology 14: 1-9.
  • NANGLU, K., J.-B. CARON, AND C. B. CAMERON. 2020a. Cambrian tentaculate worms and the origin of the hemichordate body plan. Current Biology 30 (21): 4238-4244
  • NANGLU, K., CARON, J.-B. and GAINES, R. R. 2020b. The Burgess Shale paleocommunity with new insights from Marble Canyon, British Columbia. Paleobiology, 46, 58-81.
  • SZANIAWSKI, H. 2005. Cambrian chaetognaths recognized in Burgess Shale fossils. Acta Palaeontologica Polonica, 50(1): 1-8.
  • WALCOTT, C. 1911. Cambrian Geology and Paleontology II. Middle Cambrian annelids. Smithsonian Miscellaneous Collections, 57(5): 109-145.
Other Links:

None

Nisusia burgessensis

3D animation of Nisusia burgessensis and other brachiopods (Acrothyra gregaria, Diraphora bellicostata, Micromitra burgessensis, and Paterina zenobia).

ANIMATION BY PHLESCH BUBBLE © ROYAL ONTARIO MUSEUM

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Kutorginata (Order: Kutorginida)
Species name: Nisusia burgessensis
Remarks:

Nisusia belongs within the Family Nisusiidae.

Described by: Walcott
Description date: 1889
Etymology:

Nisusia – from the Latin, nisus, meaning “labored, or striven.”

burgessensis – from Mount Burgess (2,599 m), a mountain peak in Yoho National Park. Mount Burgess was named in 1886 by Otto Klotz, the Dominion topographical surveyor, after Alexander Burgess, a former Deputy Minister of the Department of the Interior.

Type Specimens: Syntypes –USNM69690-69697 in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Other species:

Burgess Shale and vicinity: Nisusia alberta from the Trilobite Beds on Mount Stephen (Walcott, 1905, 1908). The Burgess Shale brachiopods, in particular from the Trilobite Beds on Mount Stephen, need to be re-examined (see also Brief history of research).

Other deposits: Several species are known in the Lower-Middle Cambrian of North America, Greenland, Russia, China and Australia.

Age & Localities:

Age:
Middle Cambrian, Bathyuriscus-Elrathina Zone (approximately 505 million years ago).
Principal localities:

The Walcott Quarry on Fossil Ridge.

History of Research:

Brief history of research:

Nisusia burgessensis was originally described as Orthisina alberta (Walcott, 1889) before being renamed Nisusia alberta (Walcott, 1905). Specimens of this species identified from the Walcott Quarry (Walcott, 1912) were re-described by Walcott as Nisusia burgessensis(Walcott, 1924), a combination still in use today. This species has not been studied since and is in need of revision.

Description:

Morphology:

This species has fine radiating ornamental lines (costae) and concentric lines of growth. The shell was originally mineralized. It is roughly 1.5 wider than its length. Both valves are convex, but the convexity of the ventral shell is more pronounced. The shells would have been articulated with short and small teeth, like in Diraphora, a comparable form from the Burgess Shale. Very thin bristles (setae) are present in a single specimen at the front of the shell margin. These would have been attached to the edge of the mantle along both the dorsal and ventral valves in the same way as in Micromitra.

Abundance:

Nisusia burgessensis is relatively common in the Walcott Quarry but overall represents a small fraction of the fauna (<0.3%) (Caron and Jackson, 2008).

Maximum Size:
23 mm

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Nisusia probably had a relatively short, stout pedicle attached either to the substrate or to other organisms like the sponge Pirania, to raise it above the sediment-water interface. In this way the brachiopod would have been relatively protected from flocculent mud travelling along the sediment-water interface, which could have been detrimental to its filter-feeding apparatus (located between the shells) called a lophophore. The bristles (setae) might have also helped reduce the intake of mud particles into the filter-feeding apparatus.

References:

CARON, J.-B. AND D. A. JACKSON. 2008. Paleoecology of the Greater Phyllopod Bed community, Burgess Shale. Palaeogeography, Palaeoclimatology, Palaeoecology, 258: 222-256.

WALCOTT, C. 1889. Description of new genera and species of fossils from the Middle Cambrian. United States National Museum, Proceedings for 1888: 441-446.

WALCOTT, C. 1905. Cambrian brachiopods with descriptions of new genera and species. United States National Museum, Proceedings for 1905: 227-337.

WALCOTT, C. 1908. Mount Stephen rocks and fossils. Canadian Alpine Journal, 1: 232-248.

WALCOTT, C. D. 1912. Cambrian Brachiopoda. United States Geological Survey, Monograph, 51: part I, 812 p; part II, 363 p.

WALCOTT, C. D. 1924. Cambrian and Ozarkian Brachiopoda. Cambrian Geology and Paleontology IV. Smithsonian Miscellaneous Publications, 67: 477-554.

Other Links:

None

Micromitra burgessensis

3D animation of Micromitra burgessensis and other brachiopods (Acrothyra gregaria, Diraphora bellicostata, Nisusia burgessensis, and Paterina zenobia).

ANIMATION BY PHLESCH BUBBLE © ROYAL ONTARIO MUSEUM

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Paterinata (Order: Paterinida)
Species name: Micromitra burgessensis
Remarks:

Micromitra belongs within the Family Paterinidae.

Described by: Walcott
Description date: 1908
Etymology:

Micromitra – from the Greek mikros, “small,” and mitra, “turban.”

burgessensis – from Mount Burgess (2,599 m), a mountain peak in Yoho National Park. Mount Burgess was named in 1886 by Otto Klotz, the Dominion topographical surveyor, after Alexander Burgess, a former Deputy Minister of the Department of the Interior.

Type Specimens: Holotype –USNM69646 in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Other species:

Burgess Shale and vicinity: none to date. The Burgess Shale brachiopods, in particular from the Trilobite Beds on Mount Stephen, need to be re-examined (see also Brief history of research).

Other deposits: Numerous species, all from the Cambrian, are known worldwide.

Age & Localities:

Age:
Middle Cambrian, Bathyuriscus-Elrathina Zone (approximately 505 million years ago).
Principal localities:

The Walcott and Raymond Quarries on Fossil Ridge. Additional localities are known on Mount Field, Mount Stephen, and near Stanley Glacier.

History of Research:

Brief history of research:

Originally identified as Micromitra (Iphidella) pannula by Walcott (1908) from the Trilobite Beds on Mount Stephen (see also Walcott, 1912), it was redescribed as a new species by Resser (1938). Resser’s description fails to distinguish Micromitra burgessensis from any other species of the genus, it was based upon only a single valve, and it was not illustrated. The validity of this species is questionable and needs reassessment.

Description:

Morphology:

This species is the most ornamented of the Burgess Shale brachiopods. The shell was originally mineralized. It has pronounced growth lines and fine raised lines which cut obliquely across the shell. The intersection between the different lines creates small diamonds on the surface of the shell. The valves are subcircular with the hinge nearly straight. Perhaps the most striking of the preserved features of this animal are long and slender bristles (setae) which extend far beyond the margins of the shell. These would have been attached to the edge of the mantle along both the dorsal and ventral valves.

Abundance:

Micromitra burgessensis is relatively common in the Walcott Quarry but overall represents a small fraction of the fauna (<0.3%) (Caron and Jackson, 2008). This species is also present in the Raymond Quarry on Fossil Ridge.

Maximum Size:
10 mm

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Many specimens of Micromitra burgessensis are preserved attached to spicules of the sponge Pirania, suggesting that this species was epibenthic, supported above the sediment-water interface. In this way the brachiopod would have been relatively protected from flocculent mud travelling along the sediment-water interface, which could have been detrimental to its filter-feeding apparatus (located between the shells) called a lophophore – The bristles might have also helped reduce mud particles.

References:

CARON, J.-B. AND D. A. JACKSON. 2008. Paleoecology of the Greater Phyllopod Bed community, Burgess Shale. Palaeogeography, Palaeoclimatology, Palaeoecology, 258: 222-256.

RESSER, C. E. 1938. Fourth contribution to nomenclature of Cambrian Fossils. Smithsonian Miscellaneous Collections, 97: 1-43.

WALCOTT, C. 1908. Mount Stephen rocks and fossils. Canadian Alpine Journal, 1: 232-248.

WALCOTT, C. D. 1912. Cambrian Brachiopoda. United States Geological Survey, Monograph, 51: part I, 812 p; part II, 363 p.

Other Links:

None

Mackenzia costalis

3D animation of Mackenzia costalis.

ANIMATION BY PHLESCH BUBBLE © ROYAL ONTARIO MUSEUM

Taxonomy:

Kingdom: Filterers
Phylum: Filterers
Higher Taxonomic assignment: Anthozoa? (Order: Actiniaria(?), stem group cnidarians)
Species name: Mackenzia costalis
Remarks:

Mackenzia is thought to be a cnidarian (a group which includes modern coral and jellyfish) and appears most similar to modern sea anemones (Conway Morris, 1993).

Described by: Walcott
Description date: 1911
Etymology:

Mackenzia – from Mount Mackenzie (2,461 m) near Revelstoke, southwest of the Burgess Shale. Mount Mackenzie was named in honor of Alexander Mackenzie (1822-1892), Canada’s 2nd Prime Minister.

costalis – from the Latin costalis, “pertaining to ribs.” The name refers to the lineations along the length of the animal.

Type Specimens: Lectotype –USNM57556 in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Other species:

Burgess Shale and vicinity: none.

Other deposits: none.

Age & Localities:

Age:
Middle Cambrian, Bathyuriscus-Elrathina Zone (approximately 505 million years ago).
Principal localities:

The Walcott and Raymond Quarries on Fossil Ridge. The Tulip Beds (S7) on Mount Stephen.

History of Research:

Brief history of research:

Mackenzia was first described as a holothurian, a group of echinoderms commonly known as the sea-cucumbers (Walcott, 1911). Additional fossils collected by the Geological Survey of Canada and restudy of Walcott’s collection led Conway Morris (1989, 1993) to reinterpret this animal as a cnidarian.

Description:

Morphology:

Mackenzia is a large saclike animal, up to 16 cm in height, which was anchored to hard substrates with a disc or holdfast via a short stalk; it probably stood upright. The surface of the body is folded longitudinally into 8-10 ridges. There is a large gut cavity and some evidence of internal partitioning, but little else is known of the anatomy. Tentacles are absent; the mouth was probably at the end opposite the stalk.

Abundance:

Mackenzia is very rare and represents only 0.03% of the Walcott Quarry community (Caron and Jackson, 2008).

Maximum Size:
200 mm

Ecology:

Life habits: Filterers
Feeding strategies: Filterers
Ecological Interpretations:

Mackenzia probably lived on the seabed and may have attached to animal remains such as brachiopod shells for stability. Its mode of feeding is uncertain.

References:

CARON, J.-B. AND D. A. JACKSON. 2008. Paleoecology of the Greater Phyllopod Bed community, Burgess Shale. Palaeogeography, Palaeoclimatology, Palaeoecology, 258: 222-256.

CONWAY MORRIS, S. 1989. Burgess Shale faunas and the Cambrian explosion. Science, 246: 339-346.

CONWAY MORRIS, S. 1993. Ediacaran-like fossils in Cambrian Burgess Shale-type faunas of North America. Palaeontology, 36(3): 593-635.

WALCOTT, C. D. 1911. Middle Cambrian holothurians and medusae. Cambrian Geology and Paleontology II. Smithsonian Miscellaneous Collections, 57(3): 41-68.

Other Links:

None