Arthropoda

Reconstruction of Isoxys, from Cambrian Cafe.

Belongs within: Cephalata.
Contains: Euarthropoda, Leanchoiliida.

The Arthropoda are a major clade of animals characterised by the presence of sclerotised, jointed limbs. The arthropods have been one of the most successful of all animal groups and dominate many modern environments. As defined herein, this taxon includes the Anomalocarida, a Cambrian to Devonian group of nektonic animals with large grasping appendages at the front of the head and a mouth surrounded by a radial array of sclerotised, overlapping plates (Vinther et al. 2014). A number of Cambrian forms may also represent lineages outside the arthropod crown group (Euarthropoda). Examples of these forms include the genus Isoxys, members of which had a large carapace covering most of the body, with a more or less well-developed spine at the anterior end of the carapace.

Arthropoda (see below for synonymy) LSE13
    |--Anomalocarida [Anomalocaridata, Radiodonta] VS14
    |    |--+--‘Anomalocaris’ pennsylvanica VS14
    |    |  `--+--Paranomalocaris multisegmentalis VS14
    |    |     `--+--Anomalocaris Whiteaves 1892 VS14, B95 [Anomalocarididae]
    |    |        |    `--*A. canadensis Whiteaves 1892 WB85
    |    |        `--Amplectobeluidae VS14
    |    |             |--‘Anomalocaris’ saron VS14
    |    |             `--Amplectobelua VS14
    |    |                  |--A. kunmingensis VS14
    |    |                  `--+--A. stephenensis VS14
    |    |                     `--A. symbrachiata B14
    |    `--+--Cetiocaridae VS14
    |       |    |--‘Anomalocaris’ briggsi VS14
    |       |    `--Tamisiocaris borealis VS14
    |       `--Hurdiidae VS14
    |            |--+--Schinderhannes Kühl, Briggs & Rust 2009 VS14, KBR09
    |            |  |    `--*S. bartelsi Kühl, Briggs & Rust 2009 KBR09
    |            |  `--+--Stanleycaris hirpex VS14
    |            |     `--Hurdia Walcott 1912 VS14, B95
    |            |          `--*H. victoria Walcott 1912 (see below for synonymy) DB09
    |            `--+--Peytoia Walcott 1911 VS14, WB85
    |               |    `--*P. nathorsti Walcott 1911 [=Anomalocaris nathorsti] WB85
    |               `--Laggania Walcott 1911 KBR09, WB85
    |                    `--*L. cambria Walcott 1911 WB85
    `--+--Isoxys LSE13
       |    |--I. auritus LSE13
       |    `--+--I. acutangulus LSE13
       |       |--I. curvirostrus LSE13
       |       `--I. volucris LSE13
       `--+--Nereocaris LSE13
          |    |--N. briggsi LSE13
          |    `--N. exilis LSE13
          `--+--+--Jugatacaris LSE13
             |  `--Pectocaris LSE13
             |       |--P. euryptelata LSE13
             |       `--P. spatiosa LSE13
             `--+--Odaraia Walcott 1912 LSE13, B95 [Odaraiata, Odaraiida]
                |    `--O. alata CM98
                `--+--Protocaris Walcott 1884 LSE13, G89
                   `--+--‘Canadaspis’ laevigata LSE13
                      |--+--Branchiocaris Briggs 1976 LSE13, B95 [Branchiocarata, Branchiocarida]
                      |  |    `--B. pretiosa (Resser 1929) [=Protocaris pretiosa] G89
                      |  `--Loricicaris LSE13
                      `--+--Canadaspidida LSE13
                         |    |--Canadaspis Novoshilov 1960 B95
                         |    |    `--C. perfecta (Walcott 1912) RL02
                         |    `--Perspicaris Briggs 1977 LSE13, B95
                         |         |--P. dictynna LSE13
                         |         `--P. recondita LSE13
                         `--+--Fuxianhuiida [Fuxianhuiata] LSE13
                            |    |--Shankouia LSE13
                            |    `--+--Liangwangshania LSE13
                            |       `--+--Chengjiangocaris LSE13
                            |          |    |--C. kunmingensis Yang, Ortega-Hernández et al. 2013 YO-H13
                            |          |    `--C. longiformis Hou & Bergström 1991 B95
                            |          `--+--Guangweicaris LSE13
                            |             `--Fuxianhuia LSE13
                            |                  |--F. protensa Hou 1987 B95
                            |                  `--F. xiaoshibaensis Yang, Ortega-Hernández et al. 2013 YO-H13
                            `--+--Kootenichelidae LSE13
                               |    |--Worthenella Walcott 1911 LSE13, H62
                               |    |    `--*W. cambria Walcott 1911 H62
                               |    `--Kootenichela LSE13
                               `--+--Fortiforceps foliosa Hou & Bergström 1997 LSE13, CB04
                                  `--+--Jiangfengia Hou 1987 LSE13, B95 [Jianfengiida]
                                     |    `--J. multisegmentalis Hou 1987 CB04
                                     `--+--+--Euarthropoda LSE13
                                        |  `--Pseudonotostraca G89
                                        |       |--Waptia fieldensis G89, CM98
                                        |       `--‘Burgessia’ Walcott 1912 non McCook 1894 CB04, B95 [Burgessiida]
                                        |            `--B. bella Walcott 1912 CB04
                                        `--Megacheira LSE13
                                             |--Yohoia Walcott 1912 LSE13, B95 [Yohoiida]
                                             |    `--Y. tenuis Walcott 1912 CB04
                                             |--Parapeytoia yunnanensis LSE13, KBR09
                                             `--+--Haikoucaris LSE13
                                                `--Leanchoiliida LSE13

Arthropoda incertae sedis:
  Dictyocaris Salter 1860 LS02
  Tontoia Walcott 1912 B95
  Corcorania Jell 1980 B95
  Serracaris Briggs 1978 B95
    `--S. lineata [=Anomalocaris lineata] WB85
  Cambropodus gracilis BL05
  Achanarraspis Anderson et al. 2000 N02
  Magnoculocaris blindi CB04
  ‘Leuconoe’ Bogachev 1930 non Boie 1830 (n. d.) H75
    `--*L. paradoxa Bogachev 1930 (n. d.) H75
  Velancorina Pflug 1966 G79
    `--*V. martina Pflug 1966 G79
  Occacaris B02
  Clypecaris B02
  Caryosyntrips serratus VS14

Inorganic: Hurdia davidi Chapman 1926 H75

Arthropoda [Annulosa, Brachiocaridea, Burgessidea, Canadaspididea, Cheliceromorpha, Euthycarcinomorpha, Merostomoidea, Schizoramia, Trilobitoidea, Yohoiidacea, Yohoiidea] LSE13

*Hurdia victoria Walcott 1912 [incl. Proboscicaris agnosta Rolfe 1962, H. dentata Simonetta & Della Cave 1975, P. hospes Chlupáč & Kordule 2002, Liantuoia inflata Cui & Huo 1990, P. ingens Rolfe 1962, P. obtusa Simonetta & Della Cave 1975, Amiella ornata Walcott 1911, Sidneyia ornata, Hurdia triangulata Walcott 1912, Huangshandongia yichangensis Cui & Huo 1990] DB09

*Type species of generic name indicated

REFERENCES

[B95] Bousfield, E. L. 1995. A contribution to the natural classification of Lower and Middle Cambrian arthropods: food-gathering and feeding mechanisms. Amphipacifica 2: 3–34.

[BL05] Briggs, D. E. G., B. S. Lieberman, S. L. Halgedahl & R. D. Jarrard. 2005. A new metazoan from the Middle Cambrian of Utah and the nature of the Vetulicolia. Palaeontology 48 (4): 681–686.

[B02] Budd, G. E. 2002. A palaeontological solution to the arthropod head problem. Nature 417: 271–275.

[CM98] Conway Morris, S. 1998. The Crucible of Creation. Oxford University Press: Oxford.

[CB04] Cotton, T. J., & S. J. Braddy. 2004. The phylogeny of arachnomorph arthropods and the origin of the Chelicerata. Transactions of the Royal Society of Edinburgh: Earth Sciences 94: 169–193.

[DB09] Daley, A. C., G. E. Budd, J.-B. Caron, G. D. Edgecombe & D. Collins. 2009. The Burgess Shale anomalocaridid Hurdia and its significance for early euarthropod evolution. Science 323: 1597–1600.

[G79] Glaessner, M. F. 1979. Precambrian. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A79–A118. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[G89] Gould, S. J. 1989. Wonderful Life. Vintage: London.

[H75] Häntzschel, W. 1975. Treatise on Invertebrate Paleontology pt W. Miscellanea Suppl. 1. Trace Fossils and Problematica 2^nd ed. The Geological Society of America: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[H62] Howell, B. F. 1962. Worms. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt W. Miscellanea: Conodonts, Conoidal Shells of Uncertain Affinities, Worms, Trace Fossils and Problematica pp. W144–W177. Geological Society of America, and University of Kansas Press.

[KBR09] Kühl, G., D. E. G. Briggs & J. Rust. 2009. A great-appendage arthropod with a radial mouth from the Lower Devonian Hunsrück Slate, Germany. Science 323: 771–773.

[LS02] Lange, S., & F. R. Schram. 2002. Possible lattice organs in Cretaceous Thylacocephala. Contributions to Zoology 71 (4): 159–169.

[LSE13] Legg, D. A., M. D. Sutton & G. D. Edgecombe. 2013. Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature Communications 4: 2485.

[N02] Newman, M. J. 2002. A new naked jawless vertebrate from the Middle Devonian of Scotland. Palaeontology 45 (5): 933–941.

[RL02] Rode, A. L., & B. S. Lieberman. 2002. Phylogenetic and biogeographic analysis of Devonian phyllocarid crustaceans. Journal of Paleontology 76 (2): 271–286.

[VS14] Vinther, J., M. Stein, N. R. Longrich & D. A. T. Harper. 2014. A suspension-feeding anomalocarid from the Early Cambrian. Nature 507: 496–499.

[WB85] Whittington, H. B., & D. E. G. Briggs. 1985. The largest Cambrian animal, Anomalocaris, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London 309: 569–609.

[YO-H13] Yang, J., J. Ortega-Hernández, N. J. Butterfield & X.-G. Zhang. 2013. Specialized appendages in fuxianhuiids and the head organization of early euarthropods. Nature 494: 468–471.

Cheliceriformes

Emeraldella brocki, from Walcott (1912).

Belongs within: Euarthropoda.
Contains: Pycnogonida, Euchelicerata.

The Cheliceriformes are here recognised as a group uniting the Chelicerata with related Palaeozoic fossil forms. Members of this group have a postabdomen lacking appendages, and commonly have dorsal, sessile (unstalked) eyes. Living members of this clade belong to the Chelicerata, which ancestrally have the first pair of head appendages formed as pincered chelicerae with the terminal segment opposed to a spinose projection of the penultimate segment (Cotton & Braddy 2004). The sister group of the Chelicerata may be the Vicissicaudata, a group of early Palaeozoic arthropods with a differentiated postabdomen, commonly with a long telsonic spine or appendicular derivatives on the pretelson.

Cheliceriformes [Protochelicerata]
    |--Chelicerata KBR09
    |   |--Pycnogonida RS10
    |   `--Euchelicerata RS10
    `--Vicissicaudata [Emeraldellidea] LSE13
         |--Sanctacaris Briggs & Collins 1988 CB04 [Sanctacarida, Sanctacaridea B95]
         |    |--‘Utahcaris’ orion Conway Morris & Robison 1988 B95
         |    `--Sanctacaris uncata Briggs & Collins 1988 WD02
         `--Emeraldellacea B95
              |--+--Sidneyia Walcott 1911 LSE13, CB04 [Limulavida, Sidneyidea, Sidneyiida]
              |  |    `--S. inexpectans Walcott 1911 CB04
              |  `--+--+--Molariida B95
              |     |  |    |--Molaria Walcott 1912 LSE13, CB04
              |     |  |    `--Emeraldoides Simonetta 1964 B95
              |     |  `--Emeraldella Walcott 1912 LSE13, CB04 [Emeraldellida]
              |     |       |--E. brocki Walcott 1912 CB04
              |     |       `--E. brutoni LSE13
              |     `--Cheloniellida [Cheloniellonida] LSE13
              |          |--Neostrabops Caster & Macke 1952 LSE13, H75
              |          `--+--Pseudoathron LSE13
              |             `--+--Cheloniellon Broili 1932 LSE13, B95
              |                |    `--C. calmani Broili 1932 CB04
              |                `--+--Triopus [Triopida] LSE13
              |                   `--+--Paraduslia LSE13
              |                      `--Duslia Jahn 1893 LSE13, S60
              |                           `--*D. insignis Jahn 1893 S60
              `--Aglaspidida [Aglaspida] LSE13
                   |  i. s.: Paleomerus hamiltoni Størmer 1956 CB04
                   |         Borchgrevinkium B95
                   |         Strabops [Strabopidae] B95
                   |         Khankaspis bazhanovi Repina & Okuneva 1969 CB04
                   |         Lemoneites Flower 1968 CB04
                   |--Kwanyinaspis LSE13
                   `--+--Quasimodaspis LSE13
                      `--+--+--Beckwithia LSE13
                         |  `--Kodymirus vagans Chlupác & Havlícek 1965 LSE13, CB04
                         `--+--Uarthrus LSE13
                            `--+--+--Flobertia kochi Hesselbo 1992 LSE13, CB04
                               |  `--+--Tremaglaspis LSE13
                               |     `--Chlupacaris LSE13
                               `--+--+--Australaglaspis LSE13
                                  |  `--Chraspedops LSE13
                                  `--+--Aglaspella LSE13
                                     `--+--Aglaspis Hall 1862 LSE13, B95
                                        |    `--A. spinifer Raasch 1939 CB04
                                        `--Glypharthrus LSE13

Inorganic: Sidneyia groenlandica Cleaves in Cleaves & Fox 1935 H75

*Type species of generic name indicated

REFERENCES

[B95] Bousfield, E. L. 1995. A contribution to the natural classification of Lower and Middle Cambrian arthropods: food-gathering and feeding mechanisms. Amphipacifica 2: 3–34.

[CB04] Cotton, T. J., & S. J. Braddy. 2004. The phylogeny of arachnomorph arthropods and the origin of the Chelicerata. Transactions of the Royal Society of Edinburgh: Earth Sciences 94: 169–193.

[H75] Häntzschel, W. 1975. Treatise on Invertebrate Paleontology pt W. Miscellanea Suppl. 1. Trace Fossils and Problematica 2^nd ed. The Geological Society of America: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[KBR09] Kühl, G., D. E. G. Briggs & J. Rust. 2009. A great-appendage arthropod with a radial mouth from the Lower Devonian Hunsrück Slate, Germany. Science 323: 771–773.

[LSE13] Legg, D. A., M. D. Sutton & G. D. Edgecombe. 2013. Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature Communications 4: 2485.

[RS10] Regier, J. C., J. W. Shultz, A. Zwick, A. Hussey, B. Ball, R. Wetzer, J. W. Martin & C. W. Cunningham. 2010. Arthropod relationships revealed by phylogenomic analysis of nuclear protein-coding sequences. Nature 463: 1079–1083.

[S60] Smith, A. G. 1960. Amphineura. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt I. Mollusca 1: Mollusca—General Features, Scaphopoda, Amphineura, Monoplacophora, Gastropoda—General Features, Archaeogastropoda and some (mainly Paleozoic) Caenogastropoda and Opisthobranchia pp. I41–I76. Geological Society of America, and University of Kansas Press.

[WD02] Waloszek, D., & J. A. Dunlop. 2002. A larval sea spider (Arthropoda: Pycnogonida) from the Upper Cambrian ‘Orsten’ of Sweden, and the phylogenetic position of pycnogonids. Palaeontology 45 (3): 421–446.

Pycnogonida

Austrodecus glaciale, copyright Claudia P. Arango.

Belongs within: Cheliceriformes.
Contains: Pantopoda.

The Pycnogonida, sea-spiders, are a group of highly distinctive marine arthropods with a tubular body bearing four to six pairs of walking legs. Feeding is via a tubular proboscis at the front of the cephalosoma, which also bears up to four pairs of appendages (the chelifores, palpi, ovigers and the first pair of walking legs) though the first three may each be absent. The upper Cambrian fossil larva Cambropycnogon klausmuelleri may represent the earliest record of Pycnogonida, sharing with crown-group sea-spiders the larval characters of massive chelicerae plus two post-cheliceral limbs not divided into podomeres, a weakly defined head shield, and mouth on a distinct forehead region (Waloszek & Dunlop 2002).

<==Pycnogonida
    |--Cambropycnogon Waloszek & Dunlop 2002 WD02
    |    `--*C. klausmuelleri Waloszek & Dunlop 2002 WD02
    `--Eupycnogonida [Palaeopycnogonida] WD02
         |--Palaeoisopus Broili 1928 SS04, B95 [Palaeoisopida, Palaeoisopodina]
         |    `--P. problematicus Broili 1928 WD02
         `--+--Austrodecus SS04
            |    |--A. glaciale SS04
            |    `--A. gordonae SS04
            |--Flagellopantopus blocki LSE13, CVR07
            `--+--Pantopoda SS04
               `--+--Palaeopantopus Broili 1928 SS04, B95 [Palaeopantopoda, Palaeopantopodina]
                  |    `--P. maucheri Broili 1929 WD02
                  `--Haliestes Siveter, Sutton et al. 2004 SS04
                       `--*H. dasos Siveter, Sutton et al. 2004 SS04

*Type species of generic name indicated

REFERENCES

[B95] Bousfield, E. L. 1995. A contribution to the natural classification of Lower and Middle Cambrian arthropods: food-gathering and feeding mechanisms. Amphipacifica 2: 3–34.

[CVR07] Charbonnier, S., J. Vannier & B. Riou. 2007. New sea spiders from the Jurassic La Voulte-sur-Rhône Lagerstätte. Proceedings of the Royal Society of London Series B—Biological Sciences 274: 2685–2691.

[LSE13] Legg, D. A., M. D. Sutton & G. D. Edgecombe. 2013. Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature Communications 4 (2485): 1–7.

[SS04] Siveter, D. J., M. D. Sutton, D. E. G. Briggs & D. J. Siveter. 2004. A Silurian sea spider. Nature 431: 978–980.

[WD02] Waloszek, D., & J. A. Dunlop. 2002. A larval sea spider (Arthropoda: Pycnogonida) from the Upper Cambrian ‘Orsten’ of Sweden, and the phylogenetic position of pycnogonids. Palaeontology 45 (3): 421–446.

Callipallenidae

Nymphon molleri, copyright Blair Patullo.

Belongs within: Pantopoda.

The Callipallenidae are a family of sea-spiders generally retaining chelifores but lacking palpi, though the phylogeny of Pycnogonida recovered by Siveter et al. (2004) placed Nymphon (which possesses both chelifores and palpi) and Pycnogonum (which lacks both) within the clade of callipallenid genera.

<==Callipallenidae MG-H11
    |--+--Pycnogonum [Pycnogonidae] SS04
    |  |    |--P. litorale (Ström 1762) (see below for synonymy) R23
    |  |    `--P. pusillum M62
    |  `--Pseudopallene SS04
    |       |--P. ambigua SS04
    |       |--P. chevron Staples 2007 MG-H11
    |       |--P. difficile Arango 2009 MG-H11
    |       `--P. watsonae Staples 2005 MG-H11
    `--+--Parapallene SS04
       |    |--P. australiensis (Hoek 1881) MG-H11
       |    |--P. challengeri Calman 1937 MG-H11
       |    |--P. famelica SS04
       |    `--P. haddoni Carpenter 1892 MG-H11
       `--+--Callipallene SS04
          |    |--C. brevirostri SS04
          |    `--C. novaezealandiae (Thompson 1884) MG-H11
          `--+--Propallene saengeri SS04
             `--Nymphon SS04
                  |  i. s.: N. gracile SS04
                  |         N. rottnesti Child 1975 MG-H11
                  |--N. surinamense SS04
                  `--+--N. micronesicum SS04
                     `--N. molleri SS04

Pycnogonum litorale (Ström 1762) [=Phalangium litorale, Pygnogonum (l. c.) litorale; incl. Ph. balaenarum Müller 1776] R23

*Type species of generic name indicated

REFERENCES

[MG-H11] McEnnulty, F. R., K. L. Gowlett-Holmes, A. Williams, F. Althaus, J. Fromont, G. C. B. Poore, T. D. O'Hara, L. Marsh, P. Kott, S. Slack-Smith, P. Alderslade & M. V. Kitahara. 2011. The deepwater megabenthic invertebrates on the western continental margin of Australia (100–1100 m depths): composition, distribution and novelty. Records of the Western Australian Museum Supplement 80: 1–191.

[M62] Monniot, F. 1962. Recherches sur les graviers a Amphioxus de la région de Banyuls-sur-Mer. Vie et Milieu 13: 231–322.

[R23] Roewer, C.-F. 1923. Die Weberknechte der Erde: Systematische Bearbeitung der bisher bekannnten Opiliones. Gustav Fischer: Jena.

[SS04] Siveter, D. J., M. D. Sutton, D. E. G. Briggs & D. J. Siveter. 2004. A Silurian sea spider. Nature 431: 978–980.

Pantopoda

Anoplodactylus evansi, copyright Claudia P. Arango.

Belongs within: Pycnogonida.
Contains: Callipallenidae.

The Pantopoda is the clade containing crown-group sea-spiders. Members of this group have the trunk reduced to a single segment; other possible synapomorphies include the absence of excretory organs, the presence of gonopore openings on the second limb podomere, cement glands in the larval chelicerae, and egg-carrying by the males (Waloszek & Dunlop 2002).

<==Pantopoda [Podosomata] WD02
    |--Colossendeidae MG-H11
    |    |--Hedgpethia calva Arango 2009 MG-H11
    |    |--Rhopalorhynchus MG-H11
    |    |    |--R. sibogae Stock 1959 MG-H11
    |    |    `--R. tenuissimum SS04
    |    |--Colossendeis RS10
    |    |    |--C. colossea Wilson 1881 MG-H11
    |    |    |--C. megalonix GV09
    |    |    |--C. melancholicus Stock 1975 S86
    |    |    `--C. stramenti GV09
    |    `--Colossopantopus Charbonnier, Vannier & Riou 2007 CVR07
    |         `--*C. boissinensis Charbonnier, Vannier & Riou 2007 CVR07
    `--Ammotheidae S86
         |  i. s.: Nymphonella Ohshima 1927 S86
         |           |--N. lambertensis Stock 1959 S86
         |           |--N. lecalvezi Guille & Soyer 1968 S86
         |           `--N. tapetis Ohshima 1927 S86
         |         Paranymphon bifilarium Arango 2009 MG-H11
         |         Palaeopycnogonides Charbonnier, Vannier & Riou 2007 CVR07
         |           `--*P. gracilis Charbonnier, Vannier & Riou 2007 CVR07
         |--Ascorhynchus Sars 1877 SS04, S86
         |    |  i. s.: A. arenicolum (Dohrn 1881) S86
         |    |         A. similis Fage 1941 S86
         |    |--A. tenuirostris SS04
         |    `--+--A. glaberrimus SS04
         |       `--A. ramipes SS04
         `--+--Eurycyde raphiaster SS04
            `--+--+--+--Cilunculus SS04
               |  |  |    |--C. armatus SS04
               |  |  |    `--C. sekiguchi SS04
               |  |  `--+--Palaeothea devonica Bergström, Stürmer & Winter 1980 SS04, WD02
               |  |     `--Ammothea hilgendorfi RS10
               |  `--+--+--Nymphopsis acinacispinata SS04
               |     |  `--Ammothella SS04
               |     |       |--A. biunguiculata SS04
               |     |       |--A. fistella SS04
               |     |       `--A. longipes M62
               |     `--+--Achelia RS10
               |        |    |--A. assimilis SS04
               |        |    |--A. australiensis SS04
               |        |    `--A. echinata Hodge 1864 GE02
               |        |--Tanystylum RS10
               |        |    |--T. haswelli SS04
               |        |    |--T. orbiculare RS10
               |        |    |--T. rehderi SS04
               |        |    `--T. zuytdorpi Arango 2009 MG-H11
               |        `--Rhynchothorax Costa 1861 SS04, S86
               |             |--R. alcicornis Krapp 1973 S86
               |             |--R. anophthalmus Arnaud 1972 S86
               |             |--R. architectus Child 1979 S86
               |             |--R. australis SS04
               |             `--R. philopsammum Hedgpeth 1951 S86
               `--+--Pallenopsis [Pallenopsidae] SS04
                     |    |--P. cidaribatus Child 1975 MG-H11
                     |    |--P. schmitti SS04
                     |    `--P. temperans Stock 1953 MG-H11
                     `--+--Callipallenidae SS04
                        `--Anoplodactylus Wilson 1878 SS04, S86
                             |  i. s.: A. anarthrus Loman 1908 S86
                             |         A. arescus S86
                             |         A. erectus GV09
                             |         A. eroticus GV09
                             |         A. pygmaeus M62
                             |         A. tarsalis Stock 1968 S86
                             |--+--A. longiceps SS04
                             |  `--Endeidae CVR07
                             |       |--Endeis RS10
                             |       |    |--E. laevis (Grube 1871) GE02
                             |       |    `--E. mollis SS04
                             |       `--Palaeoendeis Charbonnier, Vannier & Riou 2007 CVR07
                             |            `--*P. elmii Charbonnier, Vannier & Riou 2007 CVR07
                             `--+--+--A. insignis SS04
                                |  `--A. tenuicorpus SS04
                                `--+--A. glandulifer SS04
                                   `--+--A. evansi SS04
                                      `--+--A. batangensis SS04
                                         `--A. concavicollis SS04

*Type species of generic name indicated

REFERENCES

[CVR07] Charbonnier, S., J. Vannier & B. Riou. 2007. New sea spiders from the Jurassic La Voulte-sur-Rhône Lagerstätte. Proceedings of the Royal Society of London Series B—Biological Sciences 274: 2685–2691.

[GE02] Giribet, G., G. D. Edgecombe, W. C. Wheeler & C. Babbitt. 2002. Phylogeny and systematic position of Opiliones: a combined analysis of chelicerate relationships using morphological and molecular data. Cladistics 18: 5–70.

[GV09] Giribet, G., L. Vogt, A. Pérez González, P. Sharma & A. B. Kury. 2009. A multilocus approach to harvestman (Arachnida: Opiliones) phylogeny with emphasis on biogeography and the systematics of Laniatores. Cladistics 25: 1–30.

[MG-H11] McEnnulty, F. R., K. L. Gowlett-Holmes, A. Williams, F. Althaus, J. Fromont, G. C. B. Poore, T. D. O'Hara, L. Marsh, P. Kott, S. Slack-Smith, P. Alderslade & M. V. Kitahara. 2011. The deepwater megabenthic invertebrates on the western continental margin of Australia (100–1100 m depths): composition, distribution and novelty. Records of the Western Australian Museum Supplement 80: 1–191.

[M62] Monniot, F. 1962. Recherches sur les graviers a Amphioxus de la région de Banyuls-sur-Mer. Vie et Milieu 13: 231–322.

[RS10] Regier, J. C., J. W. Shultz, A. Zwick, A. Hussey, B. Ball, R. Wetzer, J. W. Martin & C. W. Cunningham. 2010. Arthropod relationships revealed by phylogenomic analysis of nuclear protein-coding sequences. Nature 463: 1079–1083.

[SS04] Siveter, D. J., M. D. Sutton, D. E. G. Briggs & D. J. Siveter. 2004. A Silurian sea spider. Nature 431: 978–980.

[S86] Stock, J. H. 1986. Pycnogonida (=Pantopoda). In: Botosaneanu, L. (ed.) Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) pp. 698–700. E. J. Brill/Dr. W. Backhuys: Leiden.

[WD02] Waloszek, D., & J. A. Dunlop. 2002. A larval sea spider (Arthropoda: Pycnogonida) from the Upper Cambrian ‘Orsten’ of Sweden, and the phylogenetic position of pycnogonids. Palaeontology 45 (3): 421–446.

Leanchoiliida

Reconstruction of Leanchoilia, copyright Marianne Collins.

Belongs within: Euarthropoda.

The Leanchoiliida are a group of Cambrian 'great-appendage' arthropods that bore elongate flagella on the podomeres of the great appendage.

Synapomorphies (from Cotton & Braddy 2004): Head with four segments; distal spines on terminal podomeres of endopods of second segment appendages longer than entire podomere series, terminating in annulate flagellae.

<==Leanchoiliida [Alalcomenaeidea, Leanchoiliidacea, Leanchoiliidea]
    |--Alalcomenaeus Simonetta 1970 LSE13, CB04 [Alalcomenaeida]
    |    |--A. cambricus Simonetta 1970 CB04
    |    `--A. illecebrosus (Hou 1987) CB04
    `--+--Actaeus Simonetta 1970 LSE13, CB04 [Actaeida]
       `--+--Oestokerkus LSE13
          `--Leanchoilia Walcott 1912 CB04, B95
               |  i. s.: L. hanceyi CB04
               |--L. persephone LSE13
               `--+--L. illecebrosa LSE13
                  `--L. superlata Walcott 1912 LSE13, CB04

*Type species of generic name indicated

REFERENCES

[B95] Bousfield, E. L. 1995. A contribution to the natural classification of Lower and Middle Cambrian arthropods: Food-gathering and feeding mechanisms. Amphipacifica 2: 3–34.

[CB04] Cotton, T. J., & S. J. Braddy. 2004. The phylogeny of arachnomorph arthropods and the origin of the Chelicerata. Transactions of the Royal Society of Edinburgh: Earth Sciences 94: 169–193.

[LSE13] Legg, D. A., M. D. Sutton & G. D. Edgecombe. 2013. Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature Communications 4 (2485): 1–7.

Conciliterga

Reconstruction of Kuamaia lata, from Hou and Bergström (1997).

Belongs within: Trilobitomorpha.

The Conciliterga are a group of soft-bodied arthropods related to trilobites known from the Lower and Middle Cambrian Burgess Shale and Chengjiang faunas.

Synapomorphies (from Cotton & Braddy 2004, not including Australimicola): Dorsal bulge present in exoskeleton accomodating drop-shaped ventral eyes; anteromedian margin of cephalon notched, accomodating strongly sclerotised plate; distal lobe of exopod large, teardrop-shaped, with long attachment to proximal lobe; joints between posterior tergites functional, anterior ones variably fused. (Running data matrix from Legg et al. (2013) through TNT identifies only one synapomorphy for Conciliterga including Australimicola: mediolateral spines present.)

Conciliterga [Helmetiida]
    |--Australimicola LSE13
    `--+--+--Skioldia LSE13
       |  `--+--Saperion glumaceum Hou et al. 1991 LSE13, CB04
       |     `--Tegopelte Simonetta & Delle Cave 1975 LSE13, CB04
       |          `--T. gigas Simonetta & Delle Cave 1975 CB04
       `--+--Nathorstia Walcott 1912 B95
          `--Helmetiidae CB04
               |--Helmetia Walcott 1918 CB04
               |    `--H. expansa Walcott 1918 CB04
               |--Rhombicalvaria Hou 1987 CB04, B95
               |    `--R. acantha Hou 1987 CB04
               `--Kuamaia Hou 1987 CB04, B95
                    |--K. lata Hou 1987 CB04
                    `--K. muricata Hou & Bergström 1997 CB04

*Type species of generic name indicated

REFERENCES

[B95] Bousfield, E. L. 1995. A contribution to the natural classification of Lower and Middle Cambrian arthropods: Food-gathering and feeding mechanisms. Amphipacifica 2: 3–34.

[CB04] Cotton, T. J., & S. J. Braddy. 2004. The phylogeny of arachnomorph arthropods and the origin of the Chelicerata. Transactions of the Royal Society of Edinburgh: Earth Sciences 94: 169–193.

[LSE13] Legg, D. A., M. D. Sutton & G. D. Edgecombe. 2013. Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature Communications 4 (2485): 1–7.

Lejopyge

Lejopyge laevigata, from Angelin (1851–1878).

Belongs within: Agnostida.

Lejopyge is a genus of agnostidans known from the Middle and Upper Cambrian of Eurasia (Harrington et al. 1959).

Characters (from Harrington et al. 1959): Axial furrows of both shields obsolete except near base of glabella and at upper end of pygidial axis; genae smooth or rugose; surface of pygidium smooth.

<==Lejopyge Hawle & Corda 1847 HLC03
    |--*L. laevigata (Dalman 1828) [=Battus laevigatus] HLC03
    |--L. acantha Robison 1984 HLC03
    |--L. armata (Linnarsson 1869) (see below for synonymy) HLC03
    |--L. barrandei (Hicks 1872) HLC03
    |--L. calva Robison 1964 HLC03
    |--L. elegans (Tullberg 1880) HLC03
    |--L. hybridus (Brøgger 1878) HLC03
    |--L. multifora Öpik 1979 HLC03
    |--L. seminula (Whitehouse 1939) HLC03
    `--L. sinensis Lu & Lin in Peng 1987 HLC03

Lejopyge armata (Linnarsson 1869) [=Agnostus laevigatus var. armatus, L. laevigata armata, L. laevigatus armatus (l. c.); incl. L. laevigata perrugata Westergård 1946, L. armata trigonospinosa Yang 1982, L. zhejiangensis Qiu in Qiu, Lu et al. 1983] HLC03

*Type species of generic name indicated

REFERENCES

Harrington, H. J., G. Henningsmoen et al. 1959. Systematic descriptions. In Treatise on Invertebrate Paleontology pt O. Arthropoda 1 pp. O170–O540. Geological Society of America and University of Kansas Press.

[HLC03] Hong, P. S., J. G. Lee & D. K. Choi. 2003. Trilobites from the Lejopyge armata zone (upper Middle Cambrian) of the Machari Formation, Yongwol Group, Korea. Journal of Paleontology 77 (5): 895–907.

Lisaniidae

Cranidium of Eoshengia, from here.

Belongs within: Ptychopariida.

The Lisaniidae are a group of small trilobites known from the upper Middle Cambrian of Eurasia (Hong et al. 2003).

Characters (from Hong et al. 2003): Small, convex; glabella large, subquadrate; frontal area short, flat to convex.

<==Lisaniidae
    |--Lisania Walcott 1911 [incl. Aojia Kobayashi 1935] HLC03
    |--Redlichaspis Kobayashi 1935 [=Lisaniella Chang 1963] HLC03
    |--Shengia Xiang in Egorova et al. 1963 HLC03
    |--Platylisania Zhang & Jell 1987 HLC03
    `--Eoshengia Yang 1978 HLC03
         |--*E. subquadrata Yang 1978 HLC03
         |--E. constricta Zhang 1981 HLC03
         |--E. dongqinlingia Yan in Yang et al. 1991 HLC03
         |--E. gaoqiaogouensis Yang & Liu in Yang et al. 1991 HLC03
         |--E. jiudiantangensis Yang 1978 HLC03
         |--E. paragenalata Yang 1978 HLC03
         |--E. paratenuis Yang in Yang et al. 1991 HLC03
         |--E. parva Yang in Yang et al. 1991 HLC03
         |--E. quadrata Yang 1978 HLC03
         |--E. rigida Yan in Yang et al. 1991 HLC03
         |--E. shorteglabella Yang & Liu in Yang et al. 1991 HLC03
         |--E. spinosa Yang 1978 HLC03
         |--E. sudani Jell & Hughes 1997 HLC03
         |--E. tenuis Zhang 1981 HLC03
         |--E. xinjiangensis Zhang 1981 HLC03
         `--E. youshuiensis (Yang 1978) HLC03

*Type species of generic name indicated

REFERENCES

[HLC03] Hong, P. S., J. G. Lee & D. K. Choi. 2003. Trilobites from the Lejopyge armata zone (upper Middle Cambrian) of the Machari Formation, Yongwol Group, Korea. Journal of Paleontology 77 (5): 895–907.

Cyclolorenzella

Holaspid cranidia of Cyclolorenzella sp., from Hong et al. (2003).

Belongs within: Ptychopariida.

Cyclolorenzella is a genus of trilobites known from the upper Middle Cambrian of Asia. Members of this genus have a convex preglabellar boss and small palpebral lobes at glabellar mid-length (Hong et al. 2003).

<==Cyclolorenzella Kobayashi 1960 [Diceratocephalidae] HLC03
    |--*C. quadrata (Kobayashi 1935) [=Lorenzella quadrata] HLC03
    |--C. acalle (Walcott 1905) HLC03
    |--C. caijiapingensis Yang 1978 HLC03
    |--C. convexa (Resser & Endo 1937) HLC03
    |--C. hebeiensis Wittke & Zhu in Zhu & Wittke 1989 HLC03
    |    |--C. h. hebeiensis HLC03
    |    `--C. h. tangshanensis Wittke & Zhu in Zhu & Wittke 1989 HLC03
    |--C. humilis Zhang in Qiu et al. 1983 HLC03
    |--C. kushanensis (Chu 1959) HLC03
    |--C. latisulcata Zhang in Qiu et al. 1983 HLC03
    |--C. longispinosa Wittke & Zhu in Zhu & Wittke 1989 HLC03
    |--C. parabola (Lu 1957) HLC03
    |--C. paraconvexa Yang 1978 HLC03
    |--C. pustulosa (Chu 1959) HLC03
    |--C. regularis (Walcott 1906) HLC03
    |--C. subcylindrica (Chu 1959) HLC03
    |--C. tonkinenensis (Mansuy 1916) HLC03
    |--C. tuma Yang 1978 HLC03
    |--C. uniforma Wittke & Zhu in Zhu & Wittke 1989 HLC03
    `--C. yentaiensis (Chu 1959) HLC03

*Type species of generic name indicated

REFERENCES

[HLC03] Hong, P. S., J. G. Lee & D. K. Choi. 2003. Trilobites from the Lejopyge armata zone (upper Middle Cambrian) of the Machari Formation, Yongwol Group, Korea. Journal of Paleontology 77 (5): 895–907.

Phacopida

Eccoptochile mariana, from the American Museum of Natural History.

Belongs within: Ptychopariida.
Contains: Sphaerexochinae, Pilekiinae, Cheirurinae.

The Phacopida are a group of trilobites known from the Ordovician to the Devonian. Most members of this group are distinguished by the possession of proparian facial sutures, with the suture emerging in front of the genal angle. They are divided between the Phacopina, with a broadly anteriorly expanded glabella and schizochroal eyes, and the Cheirurina, with four pairs of glabellar furrows, small holochroal eyes and a spiny pygidium (Prothero 1998).

<==Phacopida
    |--Phacopina P98
    |    |--Greenops P98
    |    `--Phacops P98
    |         |--P. crosslei Etheridge & Mitchell 1895 F71
    |         |--P. latifrons H04
    |         |--P. latigenalis Etheridge & Mitchell 1895 F71
    |         |--P. longicaudatus M87
    |         |--P. macdonaldi Fletcher 1950 F71
    |         |--P. rana P98
    |         `--P. serratus F71
    `--Cheiruroidea [Cheirurina] P98
         |--Pliomeridae PVP85
         |    |  i. s.: Emsurella Rosova 1960 PVP85
         |    |           `--E. humilla Rosova 1960 PVP85
         |    |         Pseudocybele nasuta FO99, J79
         |    |         Pliomerellus Chugaeva 1973 PVP85
         |    `--Protopliomeropinae PVP85
         |         |--Protopliomerops Kobayashi 1934 PVP85
         |         `--Rossaspis Harrington 1957 PVP85
         |              `--R. superciliosa J79
         `--Cheiruridae PVP85
              |  i. s.: Krattaspis Öpik 1937 PVP85
              |--Sphaerexochinae PVP85
              |--+--Pilekiinae PVP85
              |  `--Cheirurinae PVP85
              `--Eccoptochilinae PVP85
                   |--Foulonia Přibyl & Vaněk in Přibyl, Vaněk & Pek 1985 PVP85
                   |    `--*F. peregrina (Dean 1966) [=Ceraurinella peregrinus] PVP85
                   |--Eccoptochiloides Prantl & Přibyl 1947 PVP85
                   |    |--E. scuticauda (Barrande 1846) [incl. *E. tumescens (Barrande 1852)] PVP85
                   |    |--E. henryi Přibyl, Vaněk & Pek 1985 PVP85
                   |    `--E. octacantha (Angelin 1854) PVP85
                   |--Placoparina Whittard 1940 PVP85
                   |    `--*P. sedgwickii (McCoy 1849) PVP85
                   |         |--P. s. sedgwickii PVP85
                   |         `--P. s. shelvensis Hughes 1969 PVP85
                   `--Eccoptochile Hawle & Corda 1847 PVP85
                        |--*E. clavigera (Beyrich 1845) PVP85
                        |--E. almadenensis Romano 1980 PVP85
                        |--E. impedita Hammann 1972 PVP85
                        |--E. mariana (Verneuil & Barrande 1855) PVP85
                        |--E. perlata Hawle & Corda 1847 PVP85
                        |--E. quillieri (Tromelin in Guillier 1873) PVP85
                        `--E. scrobiculata (Angelin 1854) PVP85

*Type species of generic name indicated

REFERENCES

[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1–167.

[FO99] Fortey, R. A. & R. M. Owens. 1999. Feeding habits in trilobites. Palaeontology 42 (3): 429–465.

[H04] Haeckel, E. 1899–1904. Kunstformen der Natur. Bibliographisches Institut: Leipzig und Wien.

[J79] Jaanusson, V. 1979. Ordovician. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A136–A166. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[M87] Mitchell, J. 1887. Notes on the geology of Bowning, N.S.W. Proceedings of the Linnean Society of New South Wales, series 2, 1 (4): 1193–1204.

[PVP85] Přibyl, A., J. Vaněk & I. Pek. 1985. Phylogeny and taxonomy of family Cheiruridae (Trilobita). Acta Universitatis Palackianae Olomucensis Facultas Rerum Naturalium Geographica-Geologica XXIV 83: 107–193.

[P98] Prothero, D. R. 1998. Bringing Fossils to Life: An introduction to paleobiology. WCB McGraw-Hill: Boston.

Olenacea

Olenus gibbosus, from here.

Belongs within: Ptychopariida.

The Olenacea are a group of trilobites known from the Middle Cambrian to the Upper Ordovician (Harrington et al. 1959).

Characters (from Harrington et al. 1959): Exoskeleton subovate to elongate, opisthoparian (exceptionally proparian), micropygous to (rarely)subisopygous, with rounded or spinose genal angles. Cephalon with narrow border, small to medium-sized eyes and in most forms distinct eye ridges; glabella tapering forward, with simple, sigmoidal, or bifurcate lateral furrows (if present); preglabellar field present or absent; librigenae separated by median suture or fused together. Hypostoma probably free. Thorax with 9 to 24 segments. Pygidium with or without marginal spines.

<==Olenacea
    |--Elviniinae [Elviniidae] S80
    |    |--Wentsuia Sun 1935 S80
    |    |    |--*W. granulosa Sun 1935 S80
    |    |    |--W. iota Shergold 1980 S80
    |    |    `--‘Elrathia’ munda Resser & Endo in Endo & Resser 1937 S80
    |    `--Dunderbergia S80
    |         |--*D. nitida (Hall & Whitfield 1877) S80
    |         |--D. bigranulosa Palmer 1960 S80
    |         |--D. brevispina Palmer 1965 S80
    |         `--D. simplex Rasetti 1961 S80
    |--Pterocephaliidae S80
    |    |--Pterocephaliinae S80
    |    |    |--Sigmocheilus S80
    |    |    `--Pterocephalia S80
    |    |--Changshaniinae S80
    |    |    |--Changshania conica S80
    |    |    `--Parachangshania Chien 1958 S80
    |    |         `--‘Maladioidella’ elongata Endo 1944 S80
    |    `--Eugonocare Whitehouse 1939 [Aphelaspidinae] S80
    |         |--*E. tessellatum Whitehouse 1939 S80
    |         |--E. quadratum Henderson 1976 S80
    |         `--E. whitehousei Henderson 1976 S80
    `--Olenidae S80
         |  i. s.: Hedinia regalis Troedsson 1937 S80
         |         Porterfieldia punctata FO99
         |         Peltura scarabaeoides FO99
         |--Leptoplastus Angelin 1854 [Leptoplastinae] S80
         |    |--*L. stenotus Angelin 1854 S80
         |    `--L. rhaphidophorus Angelin 1854 S80
         `--Oleninae S80
              |--Plicatolina Shaw 1951 S80
              |    |--*P. kindlei Shaw 1951 S80
              |    |--P. lucida Lazarenko 1966 S80
              |    |--P. perlata lazarenko 1966 S80
              |    |--P. quadrata Pokrovskaya 1966 S80
              |    |--P. scalpta Harrington & Leanza 1957 S80
              |    `--P. yakutica Pokrovskaya 1966 S80
              `--Olenus LN05
                   |--O. attenuatus (Boeck 1838) LN05
                   |--O. dentatus (Westergård 1922) LN05
                   |--O. gibbosus (Wahlenberg 1821) LN05
                   `--+--O. transversus LN05
                      `--+--O. truncatus (Brünnich 1781) LN05
                         `--O. wahlenbergi (Wahlenberg 1821) LN05

*Type species of generic name indicated

REFERENCES

[FO99] Fortey, R. A. & R. M. Owens. 1999. Feeding habits in trilobites. Palaeontology 42 (3): 429–465.

Harrington, H. J., G. Henningsmoen et al. 1959. Systematic descriptions. In Treatise on Invertebrate Paleontology pt O. Arthropoda 1 pp. O170–O540. Geological Society of America and University of Kansas Press.

[LN05] Lauridsen, B. W., & A. T. Nielsen. 2005. The Upper Cambrian trilobite Olenus at Andrarum, Sweden: a case of iterative evolution? Palaeontology 48 (5): 1041–1056.

[S80] Shergold, J. H. 1980. Late Cambrian trilobites from the Chatsworth Limestone, western Queensland. Bureau of Mineral Resources, Geology and Geophysics—Bulletin 186: 1–111.