Microworld

world of amoeboid organisms

Menu

Genus Penardiophrys Mikrjukov, 2000

Diagnosis: desmothoracids enclosed by capsule composed of jointed polygonal facets; each facet bears a minute pore.

Remarks: Mikrjukov designated this genus to include Hedriocystis reticulata Penard 1904 and H. spinifera Brown, 1918. In 1997 Mayer describes H. spinifera with “numerous facets, with high edges (…). In the centre these facets have a number of small granules which look like pores.” These granules, which I also could observe, are described by Brown as fine pores. However, it is very doubtful that Brown could see the difference between granules and pores concerning the very small size of the specimens (8-20 um) and the lack of DIC microscopy in his time.
In 1968 Rainer had described Belonocystis tubistella, a species that closely resembles H. spinifera. Nicholls (2012) published TEM images of the fine structure of the scales of B. tubistella. He doesn’t consider B. tubistella as identical with H. spinifera, because “when Rainer (1968) established Belonocystis, he was well aware of the spined Hedriocystis spinifera Brown, 1918 (…) and included drawings reproduced from Brown€™s original publication.” I do not agree with Nicholls that both species are clearly different. If one compares the original drawings of Brown with the drawing of Mayer and recent photomicrographs, it is not difficult to see the agreement between both species.
However, the description of Penardiophrys excludes H. spinifera, because this species has no capsule but loose scales, which can detach from the cell, which I have observed several times. It is correct to transfer H. spinifera to the genus Belonocystis, considering B. tubistella als a junior synonym.

Hedriocystis spinifera
Hedriocystis spinifera
Hedriocystis spinifera, after Brown, 1918; H. spinifera after Mayer, 1997

Hedriocystis spinifera

Notice the “granules” in the base of some spines.

Penardiophrys spinifera

From Rainer, 1968
Recent posts

Haplomyxa spec.

Main cell body Haplomyxa spec. Description: The cell had a cylindrical flattened body from which numerous granuloreticulopodia emerged. The common shape was more or less

Read More »

Valkanovia delicatula

V. delicatula, after Valkanov, 1962 Genus Valkanovia  Tappan, 1966 Diagnosis: Shell ovoid, oblate, elliptical in cross-section, composed of elongated elliptical hyaline scales arranged in a

Read More »

Gocevia pontica

Gocevia pontica, after Valkanov, 1934 Gocevia pontica Valkanov, 1934 Diagnosis: Clearly addressed bipolarity. Body covered by a weakly flexible tectum covered with foreign bodies. The

Read More »

Nabranella

N. brevis, after Snegovaya and Alekperov, 2009 Genus Nabranella Snegovaya and Alekperov, 2009 Diagnosis: Shell oval or spherical shape without neck. Apical top flat and

Read More »

Armipyxis

Genus Armipyxis Dekhtiar, 2009 Genus Armipyxis was created by Dekhtiar (2009) to accommodate all species with internal struts. However, C. aculeata may also have struts, although

Read More »

Netzelia pseudolimnetica

N. pseudolimnetica, after Penard, 1902 Netzelia pseudolimnetica Ogden and Meisterfeld, 1989 Synonym Difflugia limnetica (Levander, 1900) Penard, 1902. D. limnetica – Pejler, 1962, Oikos, 12,

Read More »

Cylindrifflugia hiraethogii

C. hiraethogii, after Ogden. 1983 Cylindrifflugia hiraethogii (Ogden, 1983) González-Miguéns et al., 2022 Diagnosis: the shell is light yellow or transparent, thin pyriform with a distinct

Read More »

Cylindrifflugia bacillariarum

  C. bacillariarum, 103 – 114 µm – Fochteloërveen, Netherlands   Cylindrifflugia bacillariarum (Perty, 1849) n. comb. González-Miguéns et al., 2022 Diagnosis: shell transparent, colorless or

Read More »

Cylindrifflugia elegans

C. elegans, length 84-102 µm, Gaasterland Cylindrifflugia elegans (Penard, 1890) n. comb. González-Miguéns et al., 2022 Basionym: Difflugia elegans Penard, 1890 Diagnosis: shell outline rough, pyriform

Read More »

Cylindrifflugia lanceolata

C. lanceolata, shells 153-169 µm long, nuclei 23-26 µm (Naardermeer, Netherlands) Cylindrifflugia lanceolata (Penard, 1890) n. comb. González-Miguéns et al., 2022 Basionym: Difflugia lanceolata Penard,

Read More »