Nemagraptus gracilis, from the Natural History Museum.

Belongs within: Reclinata.

The Nemagraptidae are a group of graptoloids known from the Ordovician, with slender stipes that may bear lateral branches (Bulman 1970).

Characters (from Bulman 1970): Uniserial, bilaterally symmetrical, with two slender flexuous stipes having a primary angle of divergence of about 180 degrees; branches (if present) lateral, rarely paired, simple or compound; thecae elongate, typically inclined at low angles and with well marked sigmoid curvature (leptograptid type); development of leptograptid type.

    |--Pleurograptus Nicholson 1867 [=Pleurograpsus, Cladograpsus Carruthers 1858 nec Geinitz 1852 nec Emmons 1855] B70
    |    `--*P. linearis (Carruthers 1858) [=*Cladograpsus linearis] B70
    |--Amphigraptus Lapworth 1873 (see below for synonymy) B70
    |    |--*A. divergens (Hall 1859) B70 (see below for synonymy)
    |    `--‘Graptolithus’ multifasciatus Hall 1859 [=*Clematograptus multifasciatus] B70
    |--Syndyograptus Ruedemann 1908 [incl. Tangyagraptus Mu 1963] B70
    |    |--*S. pecten Ruedemann 1908 B70
    |    `--*Tangyagraptus’ typicus Mu 1963 B70
    `--Nemagraptus Emmons 1855 (see below for synonymy) B70
         |--*N. gracilis (Hall 1848) (see below for synonymy) B70
         |--N. explanatus [incl. N. explanatus var. pertenuis] F71
         `--*Geitonograptus’ suni Obut & Zubtzov 1964 B70

Amphigraptus Lapworth 1873 [=Coenograptus Hall 1868; incl. Clematograptus Hopkinson in Hopkinson & Lapworth 1875] B70

*Amphigraptus divergens (Hall 1859) B70 [=Graptolithus divergens B70, *Coenograptus divergens B70; incl. Amphigraptus divergens var. radiatus F71]

Nemagraptus Emmons 1855 [=Nemagrapsus, Helicograpsus Nicholson 1868, Stephanograptus Geinitz 1866; incl. Geitonograptus Obut & Zubtzov 1964] B70

*Nemagraptus gracilis (Hall 1848) [=Graptolithus gracilis, *Helicograpsus gracilis, *Stephanograptus gracilis; incl. N. elegans Emmons 1855] B70

*Type species of generic name indicated


[B70] Bulman, O. M. B. 1970. Graptolithina with sections of Enteropneusta and Pterobranchia. In Treatise on Invertebrate Paleontology Part V 2nd ed. (C. Teichert, ed.) pp. V1-V149. The Geological Society of America, Inc.: Boulder (Colorado), and the University of Kansas: Lawrence (Kansas).

[F70] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1-167.

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