The Burgess Shale

Scenella amii

3D animation of Scenella amii.

ANIMATION BY PHLESCH BUBBLE © ROYAL ONTARIO MUSEUM

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Unranked clade (stem group molluscs)
Species name: Scenella amii
Remarks:

Scenella is generally classified as a monoplacophoran mollusc (Knight, 1952; Runnegar and Jell, 1976). A position possibly ancestral to brachiopods (Dzik, 2010), or within the Cnidaria, has also been proposed (Babcock and Robison, 1988; Yochelson and Gil Cid, 1984).

Described by: Matthew
Description date: 1902
Etymology:

Scenella – from the Greek word skene, “tent, or shelter,” in reference to its shape.

amii – after Marc Henri Ami from the Geological Survey of Canada.

Type Specimens: Holotype –ROM8048 in the Royal Ontario Museum, Toronto, ON, Canada.
Other species:

Burgess Shale and vicinity: none

Other deposits: Dozens of species are known from the Lower Cambrian to the Lower Ordovician.

Age & Localities:

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

The Walcott and Raymond Quarries on Fossil Ridge. The Trilobite Beds and smaller localities on Mount Stephen.

History of Research:

Brief history of research:

The limpet-like appearance of Scenella led to its original classification as a mollusc, initially as a pteropod, then as a gastropod (Walcott, 1886). The first fossils of this genus known from the Burgess Shale were collected from the Trilobite Beds on Mount Stephen. These were described as Metoptoma amii by Matthew (1902), but Walcott (1908) considered other specimens from the same locality (and from the Walcott Quarry) to belong to Scenella varians, an earlier named species. Resser (1938) recognized that both species were identical and proposed a new combination, Scenella amii. In the same publication, Resser named a second species from the Trilobite Beds S. columbiana; this was based on a single specimen, originally recognized as a brachiopod with possible spines (Walcott, 1912), and remains highly dubious.

Description:

Morphology:

Each cone-shaped fossil has the form of a flat disc with a central peak, here termed “shell.” Concentric rings surround this peak, and sometimes the shell is also corrugated. The shells are stretched along one axis, making them elliptical rather than circular.

The fossils are often preserved in dense clusters and are usually oriented point-up.

No soft tissue is ever found associated with Scenella. The shell was evidently mineralized as indicated by the three-dimensional preservation and the presence of small cracks suggesting brittleness.

Abundance:

Hundreds of specimens of S. amii are known in the Walcott Quarry (2.27% of the community, Caron and Jackson, 2008). Many of these are found in dense clusters on single slabs.

Maximum Size:
10 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

If a mollusc, Scenella would have been a creeping bottom-dweller, potentially a grazer.

References:

BABCOCK, L. E. AND R. A. ROBISON. 1988. Taxonomy and paleobiology of some Middle Cambrian Scenella (Cnidaria) and hyolithids (Mollusca) from western North America. University of Kansas Paleontological Contributions, Paper, 121: 1-22.

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

DZIK, J. 2010. Brachiopod identity of the alleged monoplacophoran ancestors of cephalopods. Malacologia, 52:97-113.

KNIGHT, J. B. 1952. Primitive fossil gastropods and their bearing on gastropod evolution. Smithsonian Miscellaneous Collections, 117(13): 1–56.

MATTHEW, G. F. 1902. Notes on Cambrian Faunas: Cambrian Brachiopoda and Mollusca of Mt. Stephen, B.C. with the description of a new species of Metoptoma. Transactions of the Royal Society of Canada, 4:107-112.

RASETTI, F. 1954. Internal shell structures in the Middle Cambrian gastropod Scenella and the problematic genus Stenothecoides. Journal of Paleontology, 28: 59-66.

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

Runnegar, B. AND P. A. JELL. 1976. Australian Middle Cambrian molluscs and their bearing on early molluscan evolution. Alcheringa: An Australasian Journal of Palaeontology, 1(2): 109-138.

WALCOTT, C. D. 1886. Second contribution to the studies on the Cambrian faunas of North America. Bulletin of the United States Geological Survey, (30): 11-356.

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

WALCOTT, C. 1912. Cambrian Brachiopoda. United States Geological Survey Monograph, 51: Part 1: 1-872, Part 872: 871-363.

YOCHELSON, E. L. AND D. GIL CID. 1984. Reevaluation of the systematic position of Scenella. Lethaia, 17: 331-340.

Other Links:

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Kootenia burgessensis

Kootenia burgessensis (ROM 60761). Disarticulated specimen. Specimen dry – direct light (left) and coated with ammonium chloride sublimate to show details (right). Specimen length = 44 mm. Walcott Quarry.

© Royal Ontario Museum. Photo: Jean-Bernard Caron

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Trilobita (Order: Corynexochida)
Species name: Kootenia burgessensis
Remarks:

Trilobites are extinct euarthropods, probably stem lineage representatives of the Mandibulata, which includes crustaceans, myriapods, and hexapods (Scholtz and Edgecombe, 2006).

Described by: Resser
Description date: 1942
Etymology:

Kootenia – unspecified, but almost certainly for the Kootenay region of southeast British Columbia, or the derivative Kootenay River, both based upon the Ktunaxa or Kutenai First Nation of the same area.

burgessensis – from the Burgess Shale.

Type Specimens: Holotype (K. burgessensis) – USNM65511 in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA (Resser, 1942); Type status under review – (K. dawsoni), University of Michigan Museum of Paleontology, Ann Arbor, Michigan, USA.
Other species:

Burgess Shale and vicinity: Kootenia dawsoni; Olenoides serratus. (Species of Kootenia are no longer considered different enough from those in Olenoides to warrant placement in a separate genus, but Kootenia is retained here for ease of reference to historical literature).

Other deposits: other species attributed to Kootenia are widespread in the Cambrian of North America, and have been recorded in Greenland, China, Australia, and elsewhere.

Age & Localities:

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

The Walcott Quarry on Fossil Ridge, and nearby localities on Mount Field; K. dawsoni is known from the Trilobite Beds and elsewhere on Mount Stephen.

History of Research:

Brief history of research:

Kootenia burgessensis was established by Charles Resser based on material Walcott included in K. dawsoni. Kootenia originally appeared as a subgenus of Bathyuriscus in Walcott’s 1889 paper revising many of Rominger’s Mount Stephen trilobite identifications. Walcott named B. (Kootenia) dawsoni after G. M. Dawson of the Geological Survey of Canada as a replacement for what Rominger had illustrated as Bathyurus (?) in 1887.

In 1908, Walcott followed G. F. Matthew (1899) in calling this Dorypyge (Kootenia) dawsoni, but regarded Kootenia as a full genus in 1918. Harry Whittington included Kootenia burgessensis in his 1975 redescription of Burgess Shale appendage-bearing trilobites, illustrating a single specimen showing biramous thoracic limbs on one side. In 1994, Melzak and Westrop concluded that Kootenia could not be consistently discriminated from Olenoides using traditional characters of the spinose pygidium.

Description:

Morphology:

Hard parts: adult dorsal exoskeletons may reach 5.5 cm in length and are broadly oval in outline. In most general features, Kootenia burgessensis resembles the co-occurring Olenoides serratus, with a semi-circular cephalon bearing genal spines, a thorax of seven segments, and a semi-circular pygidium. In Kootenia, however, spines on the thoracic pleural tips and shorter and blunter, as are those around the margin of the pygidium; interpleural furrows on the pygidium are absent to very faint.

Unmineralized anatomy: based on evidence from just a few specimens, Kootenia burgessensis, like Olenoides serratus, had a pair of flexible, multi-jointed “antennae” followed by three pairs of biramous limbs on the cephalon. Pairs of similar biramous appendages were attached under each thoracic segment, with a smaller number under the pygidium. No specimens, however, show any evidence of posterior antenna-like cerci as in Olenoides.

Abundance:

Kootenia burgessensis is moderately common in the Walcott Quarry section on Fossil Ridge, as is Kootenia dawsoni in the Mount Stephen Trilobite Beds.

Maximum Size:
55 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

Adult Kootenia burgessensis walked along the sea bed, possibly digging shallow furrows to locate small soft-bodied and weakly-shelled animals or carcasses. Kootenia could probably swim just above the sea bed for short distances. Tiny larvae and early juveniles probably swam and drifted in the water column.

References:

MATTHEW, G. F. 1899. Studies on Cambrian faunas, No. 3. Upper Cambrian Fauna of Mount Stephen, British Columbia: The trilobites and worms. Transactions of the Royal Society of Canada, Series 2, Vol. 5, Section IV:39-66.

MELZAK, A. AND S. R. WESTROP. 1994. Mid-Cambrian (Marjuman) trilobites from the Pika Formation, southern Canadian Rocky Mountains, Alberta. Canadian Journal of Earth Sciences, 31:969-985.

RASETTI, F. 1951. Middle Cambrian stratigraphy and faunas of the Canadian Rocky Mountains. Smithsonian Miscellaneous Collections, 116 (5): 1-277.

RESSER, C. E. 1942. Fifth contribution to nomenclature of Cambrian trilobites. Smithsonian Miscellaneous Collections, 101 (15): 1-58.

RESSER, C. E. 1942. Fifth contribution to nomenclature of Cambrian trilobites. Smithsonian Miscellaneous Collections, 101 (15): 1-58.

ROMINGER, C. 1887. Description of primordial fossils from Mount Stephens, N. W. Territory of Canada. Proceedings of the Academy of Natural Sciences of Philadelphia, 1887: 12-19.

SCHOLTZ, G. AND G. D. EDGECOMBE. 2006. The evolution of arthropod heads: reconciling morphological, developmental and palaeontological evidence. Development Genes and Evolution, 216: 395-415.

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

WALCOTT, C. 1918. Cambrian Geology and Paleontology IV. Appendages of trilobites. Smithsonian Miscellaneous Collections, 67(4): 115-216.

WHITTINGTON, H. B. 1975. Trilobites with appendages from the Middle Cambrian, Burgess Shale, British Columbia. Fossils and Strata, No. 4: 97-136.

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Isoxys acutangulus

3D animation of Isoxys carinatus.

Animation by Phlesch Bubble © Royal Ontario Museum

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Unranked clade (stem group arthropods)
Species name: Isoxys acutangulus
Remarks:

The affinity of Isoxys is uncertain because for a long time it was known only from empty carapaces. Recent descriptions of soft parts show that the frontal appendage is similar to that of some megacheiran, or “great appendage,” taxa such as Leanchoilia, Alalcomenaeus, and Yohoia (Vannier et al., 2009; García-Bellido et al., 2009a). The affinity of Megacheira as a whole is uncertain, but it has been suggested that they either sit within the stem-lineage to the euarthropods (Budd, 2002) or they are stem-lineage chelicerates (Chen et al., 2004; Edgecombe, 2010).

Described by: Walcott
Description date: 1908
Etymology:

Isoxys – from the Greek isos, “equal,” and xystos, “smooth surface”; thus referring to the pair of smooth valves.

acutangulus – from the Latin acutus, “sharp, pointed,” and angulus, “angle”; thus referring to the acute angle of the cardinal spines.

Type Specimens: Type status under review –USNM56521 (I. acutangulus) and Holotype –USNM189170 (I. longissimus) in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Other species:

Burgess Shale and vicinity: I. longissimus from Walcott, Raymond and Collins Quarries on Fossil Ridge.

Other deposits: I. chilhoweanus from the Chilhowee Group, Tennessee, USA; I. auritus, I. paradoxus and I. curvirostratus from the Maotianshan Shale of China; I. bispinatus from the Shuijingtuo Formation, Hubei, China; I. wudingensis from the Guanshan fauna of China; I. communis and I. glaessneri from the Emu Bay Shale of Australia; I. volucris from the Buen Formation, Sirius Passet in Greenland; I. carbonelli from the Sierro Morena of Spain, and I. zhurensis from the Profallotaspis jakutensis Zone of Western Siberia. Undescribed species from Canada; Mount Cap Formation in the Mackenzie Mountains, Northwest Territories and the Eager Formation near Cranbrook. Other undescribed species in the Kaili Formation, Guizhou Province, China and the Kinzers Formation, Pennsylvania, USA. See references in Briggs et al., 2008; García-Bellido et al., 2009a,b; Stein et al., 2010; Vannier and Chen, 2000.

Age & Localities:

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

The Walcott, Raymond and Collins Quarries on Fossil Ridge. Additional localities are known on Mount Field, Mount Stephen – Tulip Beds (S7) and the Trilobite Beds, and near Stanley Glacier.

History of Research:

Brief history of research:

Walcott gave the name Isoxys to specimens from the lower Cambrian Chilhowee Group of Tennessee, USA, in 1890. He then later designated the first species from the Trilobite Beds on Mount Stephen, Anomalocaris? acutangulus (Walcott, 1908), although he placed it erroneously in the genus Anomalocaris. Simonetta and Delle Cave (1975) renamed it Isoxys acutangulus and discovered a second Burgess Shale species, I. longissimus. The original designations were based on carapaces only, making research on the ecology and affinity of Isoxys difficult. Soft parts have recently been described from the Burgess Shale taxa (Vannier et al. 2009, García-Bellido et al. 2009a).

Description:

Morphology:

The most prominent feature of Isoxys is the non-mineralized carapace, which ranged in length from 1 cm to almost 4 cm, and covered most of the body. It was folded to give two equal hemispherical valves, and had pronounced spines at the front and back. A pair of bulbous, spherical eyes protrudes forward and laterally from under the carapace. They are attached to the head by very short stalks. A pair of frontal appendages that are segmented and non-branching (uniramous) is adjacent to the eyes. The flexible appendages are curved with a serrated outline and five segments in total, including a basal part, three segments with stout outgrowths, and a pointed terminal segment.

The trunk of the body has 13 pairs of evenly spaced appendages that are segmented and branch into two (biramous), with slender, unsegmented walking limbs and large, paddle-like flaps fringed with long setae. The telson has a pair of lateral flaps. A cylindrical gut passes from the head to the ventral terminus of the telson, and is lined by paired, lobate gut glands. I. longissimus is distinguished from I. acutangulus by the presence of extremely long spines and an elongated body shape.

Abundance:

Isoxys is known from hundreds of specimens collected on Fossil Ridge. In the Walcott Quarry, Isoxys acutangulus is relatively common and represents about 0.35% of the community whereas Isoxys longissimus is extremely rare (Caron and Jackson, 2008).

Maximum Size:
40 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

The streamlined body, thin carapace, and the presence of large paddle-shaped flaps in the appendages all suggest that Isoxys was a free-swimming animal. The spines and wide telson would have been use for steering and stability in the water column. A predatory lifestyle is indicated by the large eyes, frontal appendage, and gut glands. Isoxys would have swum just above the sea floor, seeking out prey in the water column and at the sediment-water interface.

References:

BRIGGS, D. E. G., B. S. LIEBERMAN, J. R. HENDRICK, S. L. HALGEDAHL AND R. D. JARRARD. 2008. Middle Cambrian arthropods from Utah. Journal of Paleontology, 82: 238-254.

BUDD, G. E. 2002. A palaeontological solution to the arthropod head problem. Nature, 417: 271-275.

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

CHEN, J. Y., D. WALOSZEK AND A. MAAS. 2004. A new ‘great-appendage’ arthropod from the Lower Cambrian of China and homology of chelicerate chelicerae and raptorial antero-ventral appendages. Lethaia, 37: 3-20.

EDGECOMBE, G. D. 2010. Arthropod phylogeny: An overview from the perspectives of morphology, molecular data and the fossil record. Arthropod Structure & Development, 39: 74-87.

GARCÍA-BELLIDO, D. C., J. VANNIER AND D. COLLINS. 2009a. Soft-part preservation in two species of the arthropod Isoxys from the middle Cambrian Burgess Shale of British Columbia, Canada. Acta Palaeontologica Polonica, 54: 699-712.

GARCÍA-BELLIDO, D. C., J. R. PATERSON, G. D. EDGECOMBE, J. B. JAGO, J. G. GEHLING AND M. S. Y. LEE. 2009b. The bivavled arthropods Isoxys and Tuzoia with soft-part preservation from the lower Cambrian Emu Bay Shale Lagerstätte (Kangaroo Island, Australia). Palaeontology, 52: 1221-1241.

SIMONETTA, A.M. AND L. DELLE CAVE. 1975. The Cambrian non trilobite arthropods from the Burgess Shale of British Columbia. A study of their comparative morphology, taxonomy and evolutionary significance. Palaeontographia Italica, 69: 1-37.

STEIN, M., J. S. PEEL, D. J. SIVETER AND M. WILLIAMS. 2010. Isoxys (Arthropoda) with preserved soft anatomy from the Sirius Passet Lagerstätte, lower Cambrian of North Greenland. 2010. Lethaia, 43: 258-265.

VANNIER, J. AND J.-Y. CHEN. 2000. The Early Cambrian colonization of pelagic niches exemplified by Isoxys (Arthropoda). Lethaia, 35: 107-120.

VANNIER, J., D. C. GARCÍA-BELLIDO, S. X. HU AND A. L. CHEN. 2009. Arthropod visual predators in the early pelagic ecosystem: evidence from the Burgess Shale and Chengjiang biotas. Proceedings of the Royal Society of London Series B, 276: 2567-2574.

WALCOTT, C. D. 1890. The fauna of the Lower Cambrian or Olenellus Zone. Reports of the U.S. Geological Survey, 10: 509-763.

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

WILLIAM, M., D. J. SIVETER AND J. S. PEEL. 1996. Isoxys (Arthropoda) from the early Cambrian Sirius Passet Lagerstätte, North Greenland. Journal of Paleontology, 70: 947-954.

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Hazelia palmata

3D animation of Hazelia conferta and other sponges (Choia ridleyi, Diagoniella cyathiformis, Eiffelia globosa, Pirania muricata, 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: Trilobite Beds
Phylum: Trilobite Beds
Class: Demospongea (Order: Monaxonida)
Species name: Hazelia palmata
Remarks:

Hazelia is considered a primitive demosponge, close to Falospongia and Crumillospongia (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:

Hazelia – from Hazel Peak (3,151 m), the older name for Mount Aberdeen, located 4 km SSW of Lake Louise in Banff National Park, Alberta. Mount Aberdeen was named in honor of Lord Gordon in 1897, the Marquis of Aberdeen and the Governor General of Canada from 1893 to 1898.

palmata – from the Latin palm, “palm of the hand,” referring to the broad cup-shape of this sponge and its resemblance to a cupped hand.

Type Specimens: Lectotypes – USNM 66463 (H. palmata – type species), 66465 (H. delicatula), USNM 66505 (H. dignata), USNM 66473 (H. grandis), USNM 66474 (H. nodulifera), USNM 66472 (H. obscura); Holotypes – USNM 66476 (H. conferta), USNM 66779 (H. crateria), USNM 66475 (H. luteria) in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA. Holotype –ROM53573 (H. lobata) in the Royal Ontario Museum, Toronto, Canada.
Other species:

Burgess Shale and vicinity: H. conferta Walcott, 1920, H. crateria Rigby, 1986, H. delicatula Walcott, 1920, H. dignata Walcott, 1920, H. grandis Walcott, 1920, H. lobata Rigby and Collins, 2004, H. luteria Rigby, 1986, H. nodulifera Walcott, 1920, H. obscura Walcott, 1920. Most species known from the Walcott Quarry (See Rigby, 1986 and Rigby and Collins, 2004).

Other deposits: H. walcotti (Resser and Howell, 1938) from the Early Cambrian Kinzers Formation of Pennsylvania (See Rigby, 1987).

Age & Localities:

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

Burgess Shale and vicinity: Hazelia is particularly common in the Walcott Quarry and is less common in the Raymond and Collins Quarries on Fossil Ridge. Many species also occur on Mount Stephen at the Trilobite Beds, Tulip Beds (S7), and other smaller localities.

Other deposits: H. palmata Walcott, 1920 from the Middle Cambrian Marjum Formation (Rigby et al., 1997).

History of Research:

Brief history of research:

Walcott described seven species of Hazelia in his 1920 paper on the Burgess Shale sponges. The genus was redescribed by Rigby in 1986 when two new species were added and one excluded from the genus (H. mammillata now referred to Moleculospina mammillata). Rigby and Collins (2004) added another species based on new material collected by the Royal Ontario Museum.

Description:

Morphology:

Species of Hazelia have a large variation in morphology with wide cup-shaped forms (H. palmata, H. crateria, H. luteria), long cone-shaped forms (H. conferta, H. grandis, H. obscura), branched forms (H. delicatula, H. dignata), and nodular to lobate forms (H. lobata, H. nodulifera). While there is this significant variety of overall shapes, the different species of Hazelia have a common microstructure. The walls are thin and composed of small tightly packed simple spicules that form a net-like structure and diverge outwards producing a plumose pattern. The walls are perforated with small canals to allow water flow. The base of each sponge would have had a small attachment structure.

In addition to its open shield-like shape, H. palmata possesses distinct radial tracts of spicules which go beyond the margins of the sponge for at least a couple of millimeters.

Abundance:

Hazelia is very common in the Walcott Quarry and represents 9.5% of the community (Caron and Jackson, 2008).

Maximum Size:
150 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

Hazelia 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. 1986. Sponges of the Burgess Shale (Middle Cambrian), British Columbia. Palaeontographica Canadiana, 2: 105 p.

RIGBY, J. K. 1987. Early Cambrian sponges from Vermont and Pennsylvania, the only ones described from North America. Journal of Paleontology, 61: 451-461.

RIGBY, J. K. L. F. GUNTHER AND F. GUNTHER. 1997. The first occurrence of the Burgess Shale Demosponge Hazelia palmata Walcott, 1920, in the Cambrian of Utah. Journal of Paleontology, 71: 994-997.

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:

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Haplophrentis carinatus

3D animation of Haplophrentis carinatus.

Animation by Phlesch Bubble © Royal Ontario Museum

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Hyolitha (Order: Hyolithida, stem group molluscs)
Species name: Haplophrentis carinatus
Remarks:

Haplophrentis belongs to a group of enigmatic cone-shaped to tubular fossils called hyoliths that are known only from the Palaeozoic. Their taxonomic position is uncertain, but the Hyolitha have been regarded as a separate phylum, an extinct Class within Mollusca (Malinky and Yochelson, 2007), or as stem-group molluscs.

Described by: Matthew
Description date: 1899
Etymology:

Haplophrentis – from the Greek haploos, “single,” and phrentikos, “wall,” in reference to the single wall within the shell.

carinatus – from the Latin carinatus, “keel-shaped,” referring to the morphological similarity to the bottom of a boat.

Type Specimens: Lectotype –ROM8463a in the Royal Ontario Museum, Toronto, Canada.
Other species:

Burgess Shale and vicinity: none

Other deposits: H. reesei Babcock & Robinson, 1988 (type species), from the lower Middle Cambrian Spence Shale and elsewhere in Utah; H.? cf. carinatus from the Middle Cambrian Kaili deposit in China (Chen et al., 2003).

Age & Localities:

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

The Walcott, Raymond and Collins Quarries on Fossil Ridge, the Trilobite Beds on Mount Stephen and Stanley Glacier in Kootenay National Park.

History of Research:

Brief history of research:

Matthew described Hyolithes carinatus from the Trilobite Beds in 1899 based on five incomplete specimens. Babcock and Robison (1988) reviewed the original fossils, along with additional specimens collected by the Royal Ontario Museum from various Burgess Shale localities. They concluded that the species carinatus didn’t belong in Hyolithes, and established a new genus, Haplophrentis, to accommodate it.

Description:

Morphology:

Like all hyoliths, Haplophrentis had a weakly-mineralized skeleton that grew by accretion, consisting of a conical living shell (conch), capped with a clam-like “lid” (operculum), with two slender, curved and rigid structures known as “helens” protruding from the shell’s opening. The function of these helens is still debated, but one possibility was to allow settlement and stabilization on the sea floor. Haplophrentis had a wiggly gut whose preserved contents are similar to the surrounding mud.

H. carinatus usually grew to around 25 mm in length, although some specimens reached as much as 40 mm; the species is distinguished from H. reesei, its cousin from Utah, by the faint grooves on its upper surface, the more pronounced net-like pattern on its “lid” (operculum), and its wider, more broadly-angled living shell (conch).

Haplophrentis can be distinguished from the similar hyolith genus Hyolithes because it bears a longitudinal wall running down the inner surface of the top of its living-shell.

Abundance:

Haplophrentis is relatively common on Fossil Ridge and in the Walcott Quarry in particular, accounting for 0.35% of the community there (Caron and Jackson, 2008).

Maximum Size:
40 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

Haplophrentis probably moved very little; its helens appear unsuited for use in locomotion (See Butterfield and Nicholas, 1996; Martí Mus and Bergström, 2005; Runnegar et al., 1975). Whilst Haplophrentis feeding mode remains somewhat conjectural, it probably consumed small organic particles from the seafloor. Numerous specimens have been found in aggregates or in the gut of the priapulid worm Ottoia prolifica suggesting Haplophrentis was actively preyed upon and ingested (Conway Morris, 1977; Babcock and Robison, 1988).

References:

BABCOCK, L. E. AND R. A. ROBISON. 1988. Taxonomy and paleobiology of some Middle Cambrian Scenella (Cnidaria) and hyolithids (Mollusca) from western North America. University of Kansas Paleontological Contributions, Paper, 121: 1-22.

BUTTERFIELD, N. J. AND C. NICHOLAS. 1996. Burgess Shale-type preservation of both non-mineralizing and “shelly” Cambrian organisms from the Mackenzie Mountains, Northwestern Canada. Journal of Paleontology, 70: 893-899.

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

CHEN, X. Y. ZHAO AND P. WANG. 2003. Preliminary research on hyolithids from the Kaili Biota, Guizhou. Acta Micropalaeontologica Sinica, 20: 296-302.

CONWAY MORRIS, S. 1977. Fossil priapulid worms. Special Papers in Palaeontology, 20: 1-95.

MALINKY, J. M. AND E. L. YOCHELSON. 2007. On the systematic position of the Hyolitha (Kingdom Animalia). Memoir of the Association of Australasian Palaeontologists, 34: 521-536.

MARTÍ MUS, M. AND J. BERGSTRÖM. 2005. The morphology of hyolithids and its functional implications. Palaeontology, 48:1139-1167.

MATTHEW, G. F. 1899. Studies on Cambrian faunas, No. 3. Upper Cambrian fauna of Mount Stephen, British Columbia. The trilobites and worms. Transactions of the Royal Society of Canada, Series 2, 4: 39-66.

RUNNEGAR, B., J. POJETA, N. J. MORRIS, J. D. TAYLOR, M. E. TAYLOR AND G. MCCLUNG. 1975. Biology of the Hyolitha. Lethaia, 8: 181-191.

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Hamptoniella foliata

Hamptoniella foliata (ROM 43816) – Holotype. Complete specimen. Specimen height = 20 mm. Specimen dry – direct light (left), wet – polarized light (right). Trilobite Beds on Mount Stephen.

© Royal Ontario Museum. Photos: Jean-Bernard Caron

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Demospongea (Order: Monaxonida)
Species name: Hamptoniella foliata
Remarks:

Hamptoniella is a primitive demosponge, with a type of skeleton considered transitional between Hamptonia and Hazelia (Rigby, 1986). Demosponges, the same group that are harvested as bath sponges, represent the largest class of sponges today.

Described by: Rigby
Description date: 2004
Etymology:

Hamptoniella – unspecified; possibly from the town of Hampton in Virginia (see Hamptonia). The Latin suffix, ella is added to Hampton to form a diminutive.

foliata – from the Latin folia, “leaf,” in reference to the leaf like aspect of the sponge.

Type Specimens: Holotypes –ROM43816 (H. foliata wrongly referencedROM48816 in Rigby and Collins, 2004) andROM44285 (H. hirsuta) in the Royal Ontario Museum, Toronto, Canada.
Other species:

Burgess Shale and vicinity: H. hirsuta Rigby and Collins, 2004 from the Trilobite Beds on Mount Stephen.

Other deposits: none.

Age & Localities:

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

The Trilobite Beds on Mount Stephen.

History of Research:

Brief history of research:

This sponge was described by Rigby and Collins (2004) based on new material collected by the Royal Ontario Museum.

Description:

Morphology:

Hamptoniella foliata is a relatively small sponge, with its body shape varying from funnel-shaped to turbinate. The skeleton is composed of simple and straight spicules that are pointed at both ends (oxeas). The axial zone of the sponge does not have a central cavity (spongocoel) and there is no large opening (osculum). Instead a number of subvertical and relatively large canals are present in the axial area. Smaller sized canals diverge from the larger canals towards the sides and the top of the sponge. Spicules tend to be clustered and parallels to canals. H. hirsuta differs from H. foliata, by appearing more spinose.

Abundance:

H. foliata has been described based on 3 specimens and H. hirsuta based on a single specimen.

Maximum Size:
24 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

Hamptoniella 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:

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.

Other Links:

None

Hamptonia bowerbanki

Hamptonia bowerbanki (ROM 53547). Overall view and close up of a large specimen showing the long and coarse oxeas (spicules). Specimen length = 184 mm. Specimen wet – polarized light (both images). Tulip Beds (S7) on Mount Stephen.

© Royal Ontario Museum. Photos: Jean-Bernard Caron

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Demospongea (Order: Monaxonida)
Species name: Hamptonia bowerbanki
Remarks:

Hamptonia 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:

Hamptonia – unspecified, but it comes possibly from the town of Hampton in Virginia. This town is home of the Langley Memorial Aeronautical Laboratory, which Walcott helped to create when he became first chairman of the NACA Executive Committee in 1915 (predecessor of NASA).

bowerbanki – for British naturalist and palaeontologist James Scott Bowerbank (1797-1877), best known for his studies of British sponges.

Type Specimens: Lectotype –USNM66493 (H. bowerbanki) in the National Museum of Natural History, Smithsonian Institution, Washington, DC, USA. Holotype –ROM44270 (H. elongata) in the Royal Ontario Museum, Toronto, Canada.
Other species:

Burgess Shale and vicinity: H. elongata Rigby and Collins, 2004 from the east side of Mount Field in Yoho National Park.

Other deposits: H. parva, from the Middle Cambrian Wheeler and Marjum Formations in Utah (Rigby et al., 2010); H. christi from the Lower Ordovician of Morocco (Botting, 2007).

Age & Localities:

Period:
Middle Cambrian, Bathyuriscus-Elrathina Zone to late Middle Cambrian Bolaspidella Assemblage Zone (approximately 505 million years ago).
Principal localities:

Burgess Shale and vicinity: The Walcott Quarry on Fossil Ridge. The Trilobite Beds and Tulip Beds (S7) on Mount Stephen.

Other deposits: H. bowerbanki from the Middle Cambrian Wheeler and Marjum Formations in Utah (Rigby et al., 2010).

History of Research:

Brief history of research:

Hamptonia was described by Walcott in his 1920 monograph on the sponges from the Burgess Shale. Rigby (1986) redescribed the genus, considering it to be closely related to Leptomitus and included it among the monaxial demosponges. Rigby and Collins (2004) described a new species, H. elongata, from material recently collected by the Royal Ontario Museum on Mount Field.

Description:

Morphology:

Hamptonia is a medium to large sub-hemispherical to globose sponge. The skeleton is composed of simple spicules of two sizes. Bundles or singly spaced long (up to 1 cm) coarse spicules are orientated vertically upwards away from the wall. The space between these large spicules is filled by bundle of small thatched spicules. There is a narrow central cavity and the oscular opening is circular. Faint canals are visible parallel to the long spicules that would have allowed water through the skeleton. Hamptonia may be confused with the central disc of Choia. However, Hamptonia has spicules that are much finer than Choia. H. elongata mainly differs from H. bowerbanki in that it has a branched skeleton.

Abundance:

Hamptonia bowerbanki represents only 0.09 % of the Walcott Quarry community (Caron and Jackson, 2008). Hamptonia elongata is known from a single specimen.

Maximum Size:
210 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

Hamptonia 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:

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.

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: Trilobite Beds
Phylum: Trilobite Beds
Class: 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:

Period:
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: Trilobite Beds
Feeding strategies: Trilobite Beds
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

Gogia stephenensis

Gogia stephenensis (GSC 25954) – Paratype. Small specimen showing strongly ridged plates and three brachioles near the top. Specimen height = 16 mm. Specimen dry – direct light (left), dry – polarized light (right). Walcott Quarry.

© Geological Survey of Canada. Photos: Jean-Bernard Caron

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Eocrinoidea (Order: Gogiida, stem group echinoderms)
Species name: Gogia stephenensis
Remarks:

Gogia is a common eocrinoid, related to the blastozoans, an early group of echinoderms (Sprinkle, 1973).

Described by: Sprinkle and Collins
Description date: 2006
Etymology:

Gogia – from Gog Lake, 60 km southeast of Field in Mount Assiniboine Provincial Park.

stephenensis – from Mount Stephen (3,199 m), the mountain peak in Yoho National Park from which the specimens were collected. Named in 1886 for George Stephen, the first president of the Canadian Pacific Railway.

Type Specimens: Holotype –ROM57247 in the Royal Ontario Museum, Toronto, Ontario, Canada.
Other species:

Burgess Shale and vicinity: none.

Other deposits: G. prolifica Walcott 1917 (type species) from the Middle Cambrian Mount Whyte formation of Alberta; G. gondi Ubaghs, 1987 from the upper Middle Cambrian of France; G. granulosa Robinson 1965 from the early Middle Cambrian Spence Shale of Utah and the Early-Middle Cambrian of Mexico; G. gondi Ubaghs, 1987 from the the Middle Cambrian of Montagne Noire, G. hobbsi Sprinkle 1973; G. kitchenerensis Sprinkle 1973 from the Spence Shale of Utah; G. longidactylus (Walcott 1886) Robinson 1965 from the Middle Cambrian of Nevada; G. multibrachiatus (Kirk 1945) Robinson 1965 from the Middle Cambrian Bright Angel Shale, Grand Canyon, Arizona; G. ojenai Durham 1978 from the late Early Cambrian of California; G. palmeri Sprinkle 1973 from the Middle Cambrian of Idaho; G. parsleyi Zamora 2009 from the Middle Cambrian Murero Formation of Spain; and G. spiralis Robinson 1965 from the Middle Cambrian Wheeler Shale of Utah. (See complete list of references in Sprinkle, 1973 and Zamora et al. 2010.)

Age & Localities:

Period:
Middle Cambrian, 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:

Though the genus Gogia was described by Walcott in 1917 from material collected in the Lower Middle Cambrian Mount Whyte Formation, it was not recognized in the Burgess Shale until 1966 when a single specimen was discovered by the Geological Survey of Canada in the Walcott Quarry. Together with additional specimens identified in the Walcott collection, Sprinkle named this form G.(?) radiata (Sprinkle, 1973). Additional material collected by the Royal Ontario Museum led to designate the current species replacing G.(?) radiata (Sprinkle and Collins, 2006).

Description:

Morphology:

G. stephenensis consists of a rounded conical body (theca) on a short stalk with around a dozen straight arms near the top (brachioles), which in this species may branch at least once along their length. The theca is composed of a patchwork of interlocking plates. The larger plates are strongly ridged.

Abundance:

Though the genus is abundant in other deposits, Gogia is markedly rare in all the Burgess Shale localities.

Maximum Size:
40 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

Gogia was attached to the sea floor by a short calcified stalk and fed by capturing small water-borne particles with its thin, tendril-like arms. Food particles were transported from the arms to food grooves (ambulacrum) into a central mouth at the top of the theca.

References:

SPRINKLE, J. 1973. Morphology and evolution of blastozoan echinoderms. Harvard University, Museum of Comparative Zoology Special Publication: 1-284.

SPRINKLE, J. AND D. COLLINS. 2006. New eocrinoids from the Burgess Shale, southern British Columbia, Canada, and the Spence Shale, northern Utah, USA. Canadian Journal of Earth Sciences, 43: 303-322.

WALCOTT, C. D. 1917. Cambrian geology and paleontology. IV. Fauna of the Mount Whyte Formation: Smithsonian Miscellaneous Collections, 63: 61-114.

ZAMORA, S. R. GOZALO AND E. LINÑÁN. 2009. Middle Cambrian Gogiid Echinoderms from Northeast Spain: Taxonomy, Palaeoecology, and Palaeogeographic Implications. Acta Palaeontologica Polonica, 54: 253-265.

Other Links:

None

Petaloptyon danei

Petaloptyon danei (MCZ 101624) – Holotype. Lower part of a moderately complete specimen showing several panels with gaps. Specimen height = 42 mm. Specimen dry – polarized light. Trilobite Beds on Mount Stephen.

© MUSEUM OF COMPARATIVE ZOOLOGY AT HARVARD UNIVERSITY. PHOTO: DESMOND COLLINS

Taxonomy:

Kingdom: Trilobite Beds
Phylum: Trilobite Beds
Class: Calcarea (Order: Heteractinida)
Species name: Petaloptyon danei
Remarks:

Petaloptyon is considered a calcareous sponge belonging to the Family Eiffeiliidae (Rigby and Collins, 2004). Calcarea sponges are the only sponges with calcium carbonate (calcite or aragonite) spicules. They are thought to be an early branch within the phylum Porifera and are mainly found in the tropics today.

Described by: Raymond
Description date: 1931
Etymology:

Petaloptyon – from the Greek, petalon, meaning “leaf,” and ptyon, meaning “fan.” This name refers to the broad open petal-like shape of this sponge.

danei – from the Greek dan, “torch.” This name may refer to the torch-like shape of this sponge.

Type Specimens: Holotype – MCZ 101624, in the Museum of Comparative Zoology at Harvard University Cambridge, USA.
Other species:

Burgess Shale and vicinity: none.

Other deposits: none.

Age & Localities:

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

The Trilobite Beds and the Tulip Beds (S7) locality on Mount Stephen. The Walcott Quarry on Fossil Ridge.

History of Research:

Brief history of research:

Raymond (1931) named Petaloptyon danei based on a couple of specimens collected during his visits to the Trilobite Beds with Harvard students. At the time, Raymond classified this new animal as an octocoral (soft coral). In 1986, Rigby described a new sponge Canistrumella alternata, but it was later discovered that this was essentially the same form that Raymond had described in 1931 (Rigby and Collins, 2004) and Canistrumella was made a junior synonym of Petaloptyon.

Description:

Morphology:

Petaloptyon has a very distinct and unusual globlet-like shape. It has an open conical to basket-like skeleton that is composed of alternating triangular shaped panels (up to 12) that may or may not have circular to elliptical gaps within them. The walls of this sponge are very thin and composed of spicules with five rays. At the top, the oscular margin has a scalloped appearance. At the base of the sponge there is a stalk and an attachment structure.

Abundance:

Petaloptyon is a very rare sponge with only a handful of specimens known.

Maximum Size:
75 mm

Ecology:

Life habits: Trilobite Beds
Feeding strategies: Trilobite Beds
Ecological Interpretations:

Petalopyton would have lived attached to the sea floor. Food particles were extracted from the water as it passed through canals in the sponge’s wall.

References:

RAYMOND, P. E. 1931. Notes on invertebrate fossils, with descriptions of new species. Bulletin of the Museum of Comparative Zoology, Harvard University, 55(6):165-213.

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.

Other Links:

None