world of amoeboid organisms

Microcorycia spinosa. a = lateral view, b = ventral view, c = dorsal view, d = lateral view. (From Heinis 1911)


Microcorycia spinosa (Heinis, 1911) Decloitre, 1950

Diagnosis : Upper test part irregularly dome-shaped with regular corona of 7-14 long, relatively slender, tapered thorns that are longer than those of M. aculeata (L = 25-40 µm). Thorns hollow and internally structured, color brown. Upper test part covered with xenosomes consisting of soil and gravel particles. Lower test part plicate and at rest contracted. In ventral view, the lower test part shows 3-4 folds that are sometimes regularly arranged.

Dimensions: 86-110 µm, one individual 124 µm (measures excluding thorns) (Heinis 1911).

Ecology: Moss and lichens on trees and rocks (Heinis 1911). Mexico.

Remarks: This species looks very much like M. aculeata. Its status is thus questionable. Differences from M. aculeata are: Its thorns are longer, relatively slender, internally hollow and structured. The upper test part is covered with xenosomes.
Five, six or more contractile vacuoles of different sizes are spread in cytoplasm. Moreover, “…enthält das Plasma noch eine Anzahl kleiner, glänzender Körnchen.” [cytoplasm also contains a number of small, shiny granules]. (Heinis 1911). Heinis (1911) wrote on nuclei: “Meist treten kugelige Kerne auf von 10 bis 14 µm Durchmesser.” [Spherical nuclei having a diameter of 10 to 14 µm occur in most  cases.] “Die Pseudopodien sind wie bei C. flava und C. coronata etwas breit und farblos. [Pseudopodia are somewhat wide and colorless as with C. flava and C. coronata.] (Heinis 1911). Heinis (1911), too, reports on “young animals” The author wrote about them: “Bei jungen Tieren kann man oft die Bildung der Zähne resp. Dornen genau verfolgen. Zuerst hebt sich der Dornenkranz nur wenig aus der Haut in Form von kleinen, spitzen Höckern. Solche Tiere gleichen dann eher der Corycia coronata Pen. Junge Exemplare von 50 µm Grösse zeigen noch keinen Anfang in der Bildung der Dornen.” [It is often possible to closely observe the formation of teeth or thorns with young animals. First the corona of thorns rises only slightly out of the skin, consisting of small pointed protuberances. Such animals then show resemblance to Corycia coronata Pen. Young animals of a size of 50 µm do not show the beginning formation of thorns.]


State of species questionable


Microcorycia spinosa. a = ventral view, b = thorn, c = nucleus. (from Heinis, 1911)
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