Laganidae

Peronella orbicularis, from here.

Belongs within: Clypeasteroida.

The Laganidae are a group of sand dollars known from the Oligocene to the present of the tropical Indo-Pacific, as well as the Eocene of Europe (Durham 1966).

Characters (from Durham 1966): Test flattened, outline angulated to rounded; petals well developed, open, outer member of pore pair slightly elongated, pores usually conjugate; ambulacral food grooves present, simple, not reaching margin; interambulacra very narrow on oral surface, terminal apical plate rhomboidal; basicoronal plates forming pentameral star with ambulacral plates at apices of rays; no abrupt change in size of oral ambulacral plates; ambulacral plates not pseudocompound in petals; internal supports both radial and concentric; periproct oral.

<==Laganidae D66
    |--Fibulina Tornquist 1904 D66
    |    `--*F. gracilis Tornquist 1904 [incl. Fibularia voeltzkowi Tornquist 1904] M89
    |--Hupea Pomel 1883 D66
    |    `--*H. decagonale (Lesson 1883) M89 [=Laganum decagonalis M89, Scutella decagonalis D66]
    |--Peronellites Hayasaka & Morishita 1947 D66
    |    `--*P. ovalis Hayasaka & Morishita 1947 M89 [=Peronella (*Peronellites) ovalis D66]
    |--Rumphia Desor 1858 (see below for synonymy) D66
    |    `--*R. rostrata (Agassiz 1841) [=Laganum rostratum] M89
    |--Sismondia Desor 1858 D66
    |    `--*S. occitana (Defrance 1827) [=Scutella occitana] M89
    |--Jacksonaster Lambert & Thiéry 1914 D66
    |    |--*J. conchatus (M’Clelland 1840) [=Echinarachnius conchatus] M89
    |    `--J. depressum [=Laganum depressum] D66
    |--Laganum Link 1807 M89 (see below for synonymy)
    |    |--*L. laganum (Leske 1778) M89 (see below for synonymy)
    |    |--L. dickersoni D66
    |    |    |--L. d. dickersoni D66
    |    |    `--L. d. keiense D66
    |    `--L. fudsiyama D66
    `--Peronella Gray 1855 BM09, M89
         |--*P. peronii (Agassiz 1841) [=Laganum peronii] M89
         |--P. japonica D66
         |--P. lesueuri M89
         |--P. orbicularis (Leske 1778) BM09
         `--P. pellucida M89

Laganum Link 1807 M89 [incl. Echinodiscus Lambert & Thiéry 1914 nec Leske 1778 nec Worthen & Miller 1883 nec Stürtz 1899 D66, Lagana Gray 1825 D66]

*Laganum laganum (Leske 1778) M89 [=Echinodiscus laganum M89; incl. *Lagana minor Gray 1825 D66, Laganum petalodes Link 1807 D66]

Rumphia Desor 1858 [incl. Michelinia Dujardin & Hupé 1862 non de Koninck 1842, Polyaster Michelin 1859 non Gray 1840] D66

*Type species of generic name indicated

REFERENCES

[BM09] Bryce, C., & L. Marsh. 2009. Echinodermata (Asteroidea, Echinoidea and Holothuroidea) of Mermaid (Rowley Shoals), Scott and Seringapatam Reefs, Western Australia. Records of the Western Australian Museum Supplement 77: 209–220.

[D66] Durham, J. D. 1966. Clypeasteroids. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt U. Echinodermata 3 vol. 2 pp. U450–U491. The Geological Society of America, Inc., and The University of Kansas Press.

[M89] Mooi, R. 1989. Living and fossil genera of the Clypeasteroida (Echinoidea: Echinodermata): an illustrated key and annotated checklist. Smithsonian Contributions to Zoology 488: 1–51.