CATALOG OF ORIGINAL DESCRIPTIONS: Pterocodon poculum Nishimura 1992

This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.

Higher levels: rads_cat -> P -> Pterocodon -> Pterocodon poculum
Other pages this level: P. anteclinata, P. apis, P. campana, P. campanella, P. davisianus, P. favosus, P. lex, P. ornatus, P. poculum, P. tenellus

Pterocodon poculum

Citation: Pterocodon poculum Nishimura 1992
Rank: species
Type specimens: pl.8, figs.1-3; pl.13, fig 13
Type repository: Holotype n° LMMN AN0004-5, and paratypes n° LMMN AN0029-1, and LMMN AN0001-9. Laboratory of the Microfossil's study of Matsumoto, Nagano, Japan
Described on page(s) : p.350
Family (traditional): Theoperidae
Family (modern): Theocotylidae

<% linkedspecs %>

Current identification/main database link: Pterocodon poculum Nishimura 1992

Original Description
Shell of two or three or more (?) segments; cephalis subcircular with numerous small, circular pores, generally bearing a short, conical apical horn. In some specimens the apex of the cephalis has several very short conical spines. External collar stricture quite distinct. Internally with four collar pores. Cephalic structure has A, V, MB and two L; two l form part of bars of the internal septal ring and a bar of a pore of thorax. Thorax large, subspherical, rather thin walled, with three solid lateral wings on the broadest median part of the thorax; constricted toward the aperture. These wings which are stout, three-bladed in section, extend horizontally or very slightly downward. Some specimens consist of two segments with numerous teeth-shaped terminal projections from the distal thorax (remnants of the proximal abdomen). Other specimens consisting of three segments have a spindle-shaped third segment. Just below the distinct lumbar stricture, the abdomen has a row of eight or more large pores; abdominal wall thinner than the upper two segments, penetrated by sparse irregular pores without pore frames, with rather smooth surface, constricted distally, and with ragged termination.

(Based on 20 specimens) Overall height 148 µ, height of cephalis and thorax 110-119 µ, maximum width of cephalis 30-40 µ and of thorax 96-124 µ. Distinguishing characters (rw): This species is not similar to the type species Pterocodon campana (Ehrenberg 1854, pl. 36, fig. 10) of this genus. The first two segments are usually complete, but third segment is generally undeveloped in most specimens, or rarely developed as a subcylindrical segment. This species is generally similar to Calocycloma ampulla (Ehrenberg, in Foreman 1973, pl. 1, figs. 1-5) in the outline of the first two segments; however, it differs from the latter in possessing three solid lateral wings and smooth surface without byspines on the thorax.

Etymology: poculumis derived from the Latin, meaning tumbler.

Editors' Notes
The species described here is assigned doubtfully to this genus because of having an apical horn and three lateral wings.


Nishimura, A. (1992). Paleocene radiolarian biostratigraphy in the northeast Atlantic at Site 384, Leg 43, of the Deep Sea Drilling Project. Micropaleontology. 38(4): 317-362. gs


Pterocodon poculum compiled by the radiolaria@mikrotax project team viewed: 9-3-2021

Taxon Search:
Advanced Search

Short stable page link: Go to to create a permanent copy of this page - citation notes

Comments (0)

No comments yet on this page. Please do add comments if you spot any problems, or have information to share

Add Comment

* Required information
Captcha Image
Powered by Commentics