The Echinoid Directory

Notechinus Doderlein, 1905, p. 623

Diagnostic Features
  • Test low domal in profile with rounded ambitus.
  • Apical disc small, hemicyclic, with ocular plate I insert. Periproctal plates large. Genital plate 2 with swollen madreporic region. Irregular ring of tubercles surrounds periproct
  • Ambulacral zones relatively wide; plating trigeminate, with echinid-style compounding. Pore-pairs arranged in oblique rows forming a single broad adradial band. Not expanded or becoming crowded adorally.
  • Primary marginal tubercle on each ambulacral plate plus a much smaller secondary tubercle. Remainder of plate covered with miliaries and granules.
  • No perradial and interradial naked zones developed; No sutural pits.
  • Interambulacral plates wider than tall; with prominent primary tubercle flanked by a much smaller secondary tubercle on either side (two on adradial side at ambitus). Remainder of plate densely covered in variable-sized granules and miliaries.
  • Tubercles imperforate and non-crenulate as adults (weakly crenulate in juveniles).
  • Peristomial flush with no effective buccal notches. Peristomial membrane naked except for 10 buccal plates.
  • Spines short and simple.
  • Perignathic girdle with large auricles fused perradially.
  • Globiferous pedicellariae with double poison glands and single end tooth plus a single unpaired lateral tooth.
Distribution
Recent, southern South America.
Name gender masculine
Type
Echinus magellanicus Philippi, 1857, p. 130, by original designation.
Species Included
  • P. magellanicus (Philippi, 1857); Recent, Patagonia.
Classification and/or Status

Camarodonta; Temnopleuridea.

Subjective junior synonym of Pseudechinus Mortensen, 1903.

Remarks

Doderlein, L. 1905. Über Seeigel der deutschen Tiefsee-Expedition. Zoologische Anzeiger 28, 621-624.

Doderlein, L. 1906. Die Echinoiden der deutschen Tiefsee-Expedition. Wissenschaftliche Ergebnisse der Deutsche Tiefsee Expedition 1898-99 5, 63-350.

Mortensen, T. 1943. A monograph of the Echinoidea Part III.2, Camarodonta 1. C. A. Reitzel, Copenhagen.