davidfbird's Favorites

F3 Hybrid Blue-winged Warbler x Golden-winged Warbler : as described in pp 156,158 https://www.westernfieldornithologists.org/archive/V42/WB-V42(3)-webComp.pdf

"This decision recognized evidence from the zone of hybridization that a black
postocular eyeline curling down around the auriculars is typical of F3 or F4 hybrids."

Spirostomum ambiguum Ehrenberg, 1834. from the superficial river edge benthos of the freshwater segment of the estuarine Peconic River. Imaged in Nomarsdki DIC on Olympus BH2S using Splanapo 20 0.70 and SPlanapo 40 0.95 objectives plus variable phone camera cropping on Samsung Galaxy S9+. The cell measures 960 um in length. The peristome is 2/3 the length of the body with the cytostome at the posterior 2/3 location. There is a large terminal contractive vacuole with a long collecting canal reaching almost the anterior end of the cell. The macronucleus is moniliform forming a chain of connected elongate spindle shaped macronuclear nodules beginning at the anterior 40% of the cell length and extending almost to the posterior end.

"Spirostomum ambiguum Ehrenberg, 1834. [syn: Trichoda ambiguum Müller, 1786; S. ambiguum var. major Roux, 1901] 900 m several mm long. Length: width ratio about 9-17. 15-25 kineties on each side; heterogeneous, numerous (4-5) CG rows per stripe. Peristome always longer than 1/2 of the body length, often reaching 2/3. CV much shorter than body length, rarely exceeding 1/10. The color depends on cytoplasmic granules. Moniliform MAC with 12-50 (avg. 15-25) nodules not exceeding 35 45 m in length when stained by Feulgen reaction. Numerous (up to 100) MICs 1-2 m long. Mono phyletic. Only found in freshwater. Reported in central and northern Europe, England, Russia, central Africa, USA, Jamaica, India and Japan. It sometimes harbors prokaryotic symbionts in the MAC. Spirostomum ambiguum is a well-defined, easily recognizable morphospecies whose monophyly is also strongly supported by molecular sequences" (1).

"Differential diagnosis
1) Size in vivo 1-000-4000 x 48-100 um, mostly 1200-2000 um. Visible with the naked eye as a white thread. Very flexible and contractile, shortens to approximately 390-430 x200-220 um. Contracted cells cigar-shaped.
2) Shape slender to moderately broad worm-shaped, more or less parallel-sided, 10-17 times longer than wide. Front end rounded, rear end truncated. Slightly flattened laterally. Ventral side in area of ​​the mouth entrance slightly bulging.
3) Macronucleus moniliform or rosary-shaped, consists of 10-50, mostly 15-20 ellipsoids, about 18-53 x 12-24 um large nodes that form a long band that approaches the dorsal side. The number of nodes correlates positively with the age of the cell (REPAK & ISQUITH L974).
4) Contractile vacuole at the posterior end, with a long collecting duct extending forward along the dorsal side which sometimes shows ampullary extensions.
5) Close under the pellicle there are many spherical, spherical, yellowish granules arranged in elongated bands of 4-5 rows each which give the cell a yellowish to brownish color.
6) About 70-90 slightly spiraling rows of cilia, consisting of basal bodies arranged in pairs are constructed, but only the front one has a cilium.t
When the cells contract (startle reaction), the rows of eyelashes spiral around the body.
7) The adoral membrane zone extends from the anterior end to the posterior third (about 65-70 % of the body length) and turns to the right at the lower end. Parallel to the adoral membranelle zone a non-ciliated oral groove, which is bordered on the right by an undulating membrane.
8} Movement hatching, worm-like crawling and writhing. Fluidity with longitudinal rotation axis, with the front end describing a cone-shaped body of revolution. In the plankton falling floating with inclined longitudinal axis" (2).

"Spirostomum ambiguum is easy to recognize because of its size and shape, but the differentiation with S. minus causes considerable difficulties. There are many shape variations which occur, size and shape are not reliable distinguishing features. Usually S. minus is significantly slimmer and almost never reaches a length of 1 mm, while S. ambiguum is more compact, stockier and over 1 m long. Only the length of the adoral membrane zone in relation for body length (S. ambiguum: 65-70 %; S. minus: 35-50%) remains reasonably reliable distinguishing feature, but here too the differences do not seem to be too pronounced. Furthermore, the ciliates S. semivirescens have a similar size and shape (up to 2 mm, very slender, adoral membrane zone up to 50 % of body length, green through symbiontic algae) and Homalozoon vermiculare (up to 1.5 mm, 5-21 contractile vacuoles along the dorsal side, mouth small and only at the front end) as well as microturbellaria and nematodes. The characteristics 1,3 and 7 are particularly important for identification" (2).

1. Focusing on Genera to Improve Species Identification: Revised Systematics of the Ciliate Spirostomum Vittorio Boscaroa,1, Daniela Carducci, Giovanna Barbieri, Marcus V.X. Senra, Ilaria Andreoli, Fabrizio Erra, Giulio Petroni, Franco Verni, and Sergei I. Fokin. Protist, Vol. 165, 527–541, August 2014
2. FOISSNER W., BERGER H. & KOHMANN F. (1992): Taxonomische und ökologische Revision der Ciliaten des Saprobiensystems - Band II: Peritrichia, Heterotrichida, Odontostomatida. – Informationsberichte des Bayer. Landesamtes für Wasserwirtschaft, 5/92: pp 317-25.

mag. 400x

• A pond-side water/periphyton sample was taken 04/22/2024 using a small sample bottled attached to an extension pole. Air temp 61F.

Long, juggling club-shaped cells, with siliceous scales, on stalks directed toward the colony center. Two flagella per cell, one long one short. This taxon has been previously observed in this general location, https://www.inaturalist.org/observations?place_id=any&taxon_id=494360&user_id=mnold1&verifiable=any.

Video shows a slowly rotating colony, https://youtu.be/nJn1INXd_co.

Ref. https://www.keweenawalgae.mtu.edu/gallery_pages/synurophyceans.htm

Mag. 400x (1,4,6); 200x (2,3,5)

• A pond-side water/periphyton sample was taken 04/22/2024 using a small sample bottled attached to an extension pole. Air temp 61F.

Various forms of Hyalotheca dissiliens. The first 3 images show a mass of H. dissiliens zygospores. These masses are the largest I've encountered and were seen throughout the slide. The 4th image shows a segment of H. dissiliens with cells attached in filamentous form, surrounded by broad mucilaginous sheath. The last 2 images show H. dissiliens in single cell format. Both lateral views (barrel-shaped) and apical views (where the chloroplast has a stellate form) are visible.
Ref. https://www.outerhebridesalgae.uk/desmids/desmid-species.php?id=324

Paramecium nephridiatum V. Gelei, 1925 from the brackish estuarine pond Pussy's Pond, an offshoot of Acabonac Harbor. The population arose after feeding the culture with boiled wheat seeds. Imaged in Nomarski DIC on Olympus BH2S using SPlanapo 40 0.95 and SPlan 100 1.25 oil objectives plus variable phone camera cropping on Samsung Galaxy S9+.

The cells measure from 100-165 um in length. There is a large oval macronucleus usually situated slightly anterior to the cell equator and 3-4 small endosomal-type micronuclei can be observed with exact focus in the anterior end of the cell remote from the macronucleus- an important specific character of P. nephridiatum according to Fokin et al 1999 (1) The oral apparatus is situated posterior to the macronucleus with the cytostome roughly equatorial. There is an inconspicuous tuft of long caudal cilia. The two contractile vacuoles, one anterior and one posterior, have up to 15 short radiating canals and 2-3 excretory pores- another important specific characteristic of P. nephridiatum (1). There is a dense investment of subpellicuar extrusomes. The pellicle is divided into rectangular spaces on optical sectioning of the surface, a feature not mentioned by Fokin et al 1999. These features point strongly to P. nephridiatum. However, the more posterior location of the oral opening (as opposed to slightly anterior to the middle of the cell) and the peculiar pellicular division into rectangular spaces suggest that this might be a cryptic species of P. nephridiatum. Indeed, Przyboś et al 2019 describe 6 cryptic species within P. nephridiatum (2)

The cell shape with its rounded posterior end, and broad anterior part is of the "bursaria" type (Wichterman 1986) or "woodruffi" type according to Jankowski (1969). The oral opening is situated a little anterior to the middle of the cell. The cell surface is uniformly ciliated except for several long caudal cilia located close to the posterior end of the dorsal side, but not on the top. The abundant subpellicular trichocysts are distributed uniformly. Specimens were about 145 x 47 um long in vivo but shrank 10% after the silver nitrate impregnation. In silver-impregnated specimens, there were ~38 rows of ventral kineties and ~35 dorsal kineties. The preoral suture is distinct, but the postoral suture is very obscure. The cytoproct is situated in the posterior third. The vestibular zone is conspicuous and is terminated by the distinctive shape of the buccal opening. Two peniculi and open quadrulus are located on the dorsal and left wall of the buccal cavity. The endoral membrane is situated along the entire right edge of the buccal opening but its dikinetids are not recognizable in all specimens. It has 15 dikinetids on the average. The buccal cavity size various around 30 um. On the dorsal side of the body the contractile vacuole pores are very distinctive both on impregnated specimens as well as in living cells. Usually, both contractile vacuoles have more than one pore each, typically two or three. However, we have found two stocks (WCh-1 and WS-12) where one of the contractile vacuoles quite often (up to 50%) had only one pore. Both contractile vacuoles usually have 8-14 collecting canals, ten on average. Numerous crystals were very often found in the cytoplasm, but their quantity and location varied, probably depending on the culture conditions. The nuclear apparatus is located in the anterior part of the cell. One slightly ellipsoid or ovoid macronucleus, ~30x36 um in living cell and ~17x23 um in stained cells, on average, resides just anterior to the equator of the cell. In Feulgen-stained cells the macronucleus has a very intense colour. The three to four spherical micronuclei of the "endosomal" type (Fokin 1997), ~3 um in diam. (on average) are distributed irregularly along the anterior part of cell. Endocytobiotic bacteria are often found in the cytoplasm (Fokin 1989) and can also be found in the perinuclear space and in the macronucleus (Fokin 1989; Fokin and Sabaneyeva 1997)" (1).

"Swimming behavior - During swimming this species spirals on its long axis in both directions (Fokin 1987). We could not find any simple triggers (food, time) for changing this swimming direction. Typically, "left spiral swimmers" and "right spiral swimmers" were present at the same time in the culture. During the several years of investigation of this trait there was some preference of the cells from the same stocks to spiral in the left direction. Remarks- Gelei (1925) described a new species of Paramecium, Paramecium nephridiatum, based on the material which he had found in his laboratory aquarium. This population was in fact a mixture of the new species and Paramecium caudatum (Gelei 1938). This was the reason why some features of the new ciliate were similar to P. caudatum so that no one recognized this new species in nature, though reference to P. nephridiatum was made by Kahl (1931) and Kalmus (1931). Gelei (1938) redescribed the species from a native population (Tisza River, Szeged, Hungary) using a "clean culture". For unknown reasons, this new description did not attract the attention of protozoologists and in all subsequent reviews, P. nephridiatum was considered a nonvalid species (Vivier 1974; Wichterman 1953, 1986) even when the article of Gelei (1938) was listed in the references. Only once was P. nephridiatum mentioned in a short abstract as a species living in Florida, USA (Bovee 1983), although characters of the species were not listed in this publication. Since 1983, one of us (S. F) has repeatedly collected a species of Paramecium with multiple contactile vacuole pores, which is a distinctive trait of P. nephridiatum, although it was considered for a time as a feature of Paramecium woodruffi (Agamaliev 1983; Fokin 1986), Jankowski (pers. commun.)" (1).

"Occurrence and ecology- A number of stocks of P. nephridiatum were isolated from the sea shores of northern Europe: the North, Baltic, White, and Barents Sea coasts. It was detected during sampling in Woods Hole, MA, USA, Atlantic Ocean and on Sakhalin Island, Sea of Okhotsk. The salinity of these samples varied from 1.5-32 % The species was also found in a fresh-water body in Jerusalem Zoo, Israel. Samples were taken mainly during the summer, from mid-April (Wood Hole) to November (North Sea coast).

Sampling of the same wild population of P. nephridiatum (Sredny Island, White Sea, Russia) has been repeated every year since 1990 to observe long-time changes in the population, as well as the euryhaline ability of the species. This population was present at salinities from 4-35% and in the temperature range from 10-25” C. Very often the populations of P. nephridiatum occurred at the lower limit of oxygen concentrations. They were mainly feeding on bacteria. In the same samples these other ciliates were usually found: Prorodon sp., Frontonia marina, Metopus sp., P. calkinsi, P. woodruffi, and sometimes P. duboscqui" (1).

1. Sergei I. Fokin, Thorsten Stoeck, and Helmut J. Schmidt; Rediscovery of Paramecium nephridiatum Gelei, 1925 and its Characteristics. J.Eukaryot.Microbiol. 46(4):416-426, 1999
2. Evaluation of the molecular variability and characteristics of Paramecium polycaryum and Paramecium nephridiatum, within subgenus Cypriostomum (Ciliophora, Protista). Ewa Przyboś, Maria Rautian, Alexandra Beliavskaia, Sebastian Tarcz . Mol Phylogenet Evol . 2019 Mar:132:296-306