world of amoeboid organisms

Menu

Centrohelida Kühn, 1926

Key to the genera:

1

Cell naked or surrounded by organic elements

2

Cell surrounded by siliceous elements

5

2

Cell surface naked; axopodia with prominent extrusomes and normally stretched across the substratum.

Cell surrounded by a mucous layer; axopodia not with prominent extrusomes and not stretched across the substratum.

 

3

3

Mucous layer embedded with organic spicules

4

Mucous layer fimbriated, without organic spicules

4

Spicules mainly tangentially arranged

Spicules radially arranged 

5

Cell covered by tangentially and loosely arranged plate-scales; these plate-scales are elliptical to spindle-shaped or rod-like

6

Cell with two types of scales: tangentially arranged elliptical plate-scales and radially arranged (spine-)scales

10

6

Scales are slightly curved solid needles or rods 

Scales are broadly elliptical to spindle-shaped, but never rod-shaped

                                         

 

 

 

7

7

Cell with one type of plate-scales; spindle-shaped plates may occur. 

8

Cell with two types of plate-scales, both having a different morphology

 

9

8

Plate-scales monolayered, with a hollow inflected margin and with a smooth or reticulate texture.  

Plate-scales consisting of an upper and lower plate connected by internal radial septa. 

9

Plate-scales of the inner layer are flattened, simple in structure, usually ornamented with an axial rib.

Plate-scales of the inner layer small. without a hollow marginal rim; plate-scales of the outer layer larger , with a well-developed sternum and radiating ribs. The base of the sternum may be expanded and concave to create a velum-like extension of the scale.

10

Radial elements tube-shaped, trumpet-shaped or funnel-shaped

11

Radial elements spine-like

12

11

With one type of funnel-shaped radial ele­ments; plate scales without broad marginal rim

Two types of radial elements: funnel-shaped and trumpet-shaped or tube-like; plate scales with broad marginal rim

12

Spine-scales consist of a shaft and two lateral wings, resembling a spoon, spade or feather

13

Spine-scales consist of a shaft and a discrete circular or heart-shaped base-plate

14

13

Radial spine-scales consist of a shaft and a thin, membranous basal region which may extend along the shaft and may form a stalk-like protrusion at the base of the spicule 

Pterocystis erinaceoides 1

The radial scales have a shaft with two lateral wings extending along it, and a basal wing oriented perpendicular to the lateral ones

Pterocystis

14

Base-plates of spine-scales are heart-shaped; the shafts attach centrally

Base-plates of spine-scales are circular; shafts attach centrally

Recent posts

Sphenoderia compressa

Sphenoderia compressa, after Badewitz, 2002 Sphenoderia compressa Badewitz, 2002 Diagnosis: Test ovoid, oval in cross section, hyaline, covered with relatively small, oval, rather irregularly arranged

Read More »

Tracheleuglypha elongata

T. elongata, A-C after Thomas and Gauthier-Lièvre, 1959; D after Van Oye, 1959 Tracheleuglypha elongata Van Oye, 1959 Diagnosis: Test similar to T. dentata, but

Read More »

Tracheleuglypha acolla

T. acolla, after Bonnet and Thomas, 1960 Tracheleuglypha acolla Bonnet and Thomas, 1955 Diagnosis: Test ovoid, non compressed, round in cross-section, with large oval overlapping

Read More »

Cyclopyxis kahli oblonga

C. kahli f. oblonga , after Tarnogradskii, 1959 Cyclopyxis kahli f. oblonga  (Tarnogradskii, 1959) Centropyxis kahli f. oblonga Tarnogradskii, 1959 Diagnosis:  Test with all the

Read More »

Cyclopyxis leclercqi

Cyclopyxis leclercqi – from Beyens and Chardez, 1986 Cyclopyxis leclercqi Beyens and Chardez, 1986 Diagnosis: Shell circular in apertural view, dorso-ventrally compressed with a swollen

Read More »

Haplomyxa saranae

Haplomyxa saranae Dellinger, 2014 Diagnosis: cell body from small rounded (0.1 mm) to large elongated shape (up to 3.5 x 0.3 mm), usually flat but

Read More »