Main Content
< Top page

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Apicoporus

Apicoporus Sparmann, Leander & Hoppenrath, 2008 (ref. ID; 6734 original paper)

Alveolata Cavalier-Smith, 1991: Dinozoa Cavalier-Smith, 1981 emend. Cavalier-Smith & Chao, 2004: Dinoflagellata Butschli, 1885 emend. Fensome et al., 1993 (ref. ID; 6734)

[ref. ID; 6734]
Description; Athecate, dorso-ventrally flattened cells with a small, low and wide, beak-shaped, asymmetrical episome with an apical pore beneath a hook-shaped apical protrusion. Descending cingulum with its distal end not connected to the sulcus. Narrow and shallow sulcus on the hyposome, extending as deeper furrow onto the episome and running down to the posterior cell end where it terminates into a semicircular posterior cell indentation (notch). Posterior ventral 'flap' partly covering the notch. With or without cryptic photosynthetic plastids. Vegetative cells with internal dinoflagellate-pellicle. (ref. ID; 6734)
Etymology; Latin apic, from apex = top end; Latin porus = opening/pore; due to the presence of an apical pore which has so far only been reported in thecate dinoflagellates. (ref. ID; 6734)
Type species; Apicoporus glaber (Hoppenrath & Okolodkov) Sparmann, Leander & Hoppenrath n. comb. (ref. ID; 6734)
  1. Apicoporus glaber (Hoppenrath & Okolodkov) Sparmann, Leander & Hoppenrath n. comb. (ref. ID; 6734)
    Basionym; Amphidinium glabrum Hoppenrath & Okolodkov 2000, Eur. J. Phycol. 35, p.62 (ref. ID; 6734)
  2. Apicoporus parvidiaboli Sparmann, Leander & Hoppenrath, 2008 (ref. ID; 6734 original paper)

Apicoporus glaber (Hoppenrath & Okolodkov) Sparmann, Leander & Hoppenrath n. comb. (ref. ID; 6734)

Basionym

Amphidinium glabrum Hoppenrath & Okolodkov 2000, Eur. J. Phycol. 35, p.62 (ref. ID; 6734)

Descriptions

Its size varied from 30 to 50 um in length and 16 to 30 um in width. It was observed to move with the apical end leading while rotating around its longitudinal axis, but was mostly attached to the bottom of the Petri dish. Most studied cells showed golden brown coloration especially at the posterior end. Many specimens also show food bodies in the apical half of the cell. All cells demonstrated an almost quadrangular, elongated shape with almost parallel sides, were dorsoventrally compressed and had a symmetrically rounded posterior end. The beak-shaped asymmetrical episome took up about one eights of the cell length. On the ventral side, the sulcus reached into the episome and continued to the antapical end where it terminated at the indentation. The sulcus was displaced to the right by about one quarter cell width. At the apex, an apical hook-like protrusion was present where the sulcus ended. The apical protrusion sat above an apical pore. The cingulum was descending by about six cingulum width and the distal end did not connect to the sulcus. A semicircular indentation was found at the antapex and sat symmetrically along the centre line of the cell. A protrusion ('flap') at the antapical end of the sulcus covered most of the indentation. The nucleus was located in the lower cell half. (ref. ID; 6734)

Apicoporus parvidiaboli Sparmann, Leander & Hoppenrath, 2008 (ref. ID; 6734 original paper)

Descriptions

Athecate, dorso-ventrally flattened cells with a small, low and wide, beak-shaped, asymmetrical episome with an apical pore beneath a hook-shaped apical protrusion. Cells are 27-65 um long and 18-40 um wide. Episome about one-eighth of the cell length. Cingulum descending by about four cingulum widths, with its distal end not connected to the sulcus. Narrow and shallow sulcus on the hyposome, extending as deeper furrow onto the episome and running down to the posterior cell end where it terminates into a semicircular posterior cell indentation (notch). Posterior ventral 'flap' partly covering the notch. With a few or without cryptic photosynthetic plastids. Nucleus in the posterior cell half. Cells with dinoflagellate-pellicle. Three morphotypes: (1) cells with a more or less tapered and oblique posterior end and little horn formation; (2) cells with parallel sides and two more or less equal sized horns at the antapex; and (3) cells with a sack-like appearance and one horn (left) more preeminent than the other. (ref. ID; 6734)

Remarks

Three main morphotypes of Apicoporus parvidiaboli n. sp. were observed at sites in Bamfield and Vancouver, BC, Canada. The cell size ranged from 27 to 65 um long and 18 to 40 um wide. Cells were either swimming in an apical direction while rotating around their longitudinal axis or attached to the bottom of the Petri dish. No vegetative cyst formation was observed. Some specimens possessed golden brown pigments near the posterior end of the cell or around the nucleus, while others were completely colorless. This variation in pigmentation was evident even within the same morphotype. All morphotypes of this species showed some level of horn formation at the posterior end of the cell and could be categorized into one of three groups: (1) "oblique antapex" -smaller cells (approx. 19 um wide, 29 um long) with a more or less tapered antapex, oblique posterior ends and very little horn formation; (2) "horned antapex" -cells that displayed parallel sides and a more symmetrically arranged antapex with two horns of equal length; and (3) "sack-shaped" -larger cells (approx, 50 um wide, 78 um long) with a sack-like appearance, a more or less oblique antapex and one horn that is more prominent than the other. However, variation in cell morphology within each morphotype overlapped in a way that eliminated discrete discontinuities between the three categories. (ref. ID; 6734)

Etymology

Latin parvus = small; diabolus = devil; due to the presence of at least one but mostly two horns at the posterior end. (ref. ID; 6734)

Type locality

Brady's Beach, Bamfield, British Columbia, Canada. (ref. ID; 6734)