Dear Priit, every year in eastern Gulf of Finland, Koporskaya bay, i see Charophytes  which is covered by cladophora (it is fouled by epiphyts not so abundant, as other macrophytes, but it have).

Dear Priit,

Your foto looks interesting. Did Ceramium occur just on a few specimens or did it cover wide areas?

I do also not know if Chara was still healthy and in good physiological condition. Allelochemicals have also a limited area of  action, so mainly specimens tightly attached might be heavily influenced by the release of allelochemicals.

We are focusing on allelopathic effects of stoneworts on other algae (see also publications below) in mainly freshwater systems. We found some micro-epiphytes, but with significantly lower abundance compared to macrophytes with similar morphology. From our field work, filamentous algae are mostly lacking in Chara fields.

Good luck!

Michael

Dear Michael, thank you for papers. It us very interesting, because in our field work we met charophytes together with filamentous algae. But abundance of filamentous algae in this sites  were lower.

Dear Priit if have seen also several epiphytes on Chara sp., can you see if ceramiun is also going inside the Chara cells as an endophyte?

Yes, epiphytes also on brackish Chara hornemannii, lots of diatoms and Batophora oerstedii in South Florida, USA

Indeed, for example: Blindow I. 1987. THE COMPOSITION AND DENSITY OF EPIPHYTON ON SEVERAL SPECIES OF SUBMERGED MACROPHYTES. Aquatic Botany, 29 (1987) 157-168.

I have observed some Oedogonium sp. and other filamentous algae on Charales (as reported in the paper cited by Nicolás). On the other hand there is some Coleochaete (as C. nitellarum) that are able to grow endophytically through the cell wall of Nitella and other uncalcified members of the Charales. See http://onlinelibrary.wiley.com/doi/10.1046/j.1529-8817.2002.01174.x/pdf

Dear colleague: this paper describes epiphytes growing on Chara connivens: Blanco S, Novais MH, Hoffmann L, Ector L 2009. Eolimna becaresii sp. nov., a new diatom taxon from Spanish shallow lake. Diatom Res. 24: 487-494

Dear Michael, thank You for these papers. Ceramium was not so abundant on Chara, covered ca 10% C. aspera thalli in quantitative samples. In brackish waters I have seen several filamentous macroalgae in chara fileds, but most of them is not attached to chara but is entangeled into chara. I added a picture and it looks like Ceramium is not endophytic in our case.

Please find enclosed paper on the diatom composition on some Charophyceae taxa investigated in different freshwater ecosystems in Bosnia and Herzegovina, Croatia and Montenegro during 2007.

My best regards Nenad Jasprica

Although charophytes are claimed to be very effective in allelopathic interactions and the lack of epiphytic algae on the surface of their thalli is given as an evidence of this effectiveness, I frequently observe in the field charophytes abundantly covered by filamentous algae, particularly at shallow littoral sites, close to the lake shore. This seems to be a case for aquatic environments in which waters were fertilized but visibility, a basic factor of charophyte occurrence, still allows charophytes to grow. The density of filaments often makes the charophyte species identification problematic! Sometimes Rivularia forms characteristic spherical colonies on the charophyte stems or branchlets. During SEM study of the charophyte thalli surface we also observed  a diverse community of attached diatoms.

Best regards, Mariusz Pelechaty

Dear Priit,

As Mariusz, I frequently observed filamentous algae on stoneworts. Actually not only filamentous algae. Generally in Italian volcanic lakes I can found a film of diatoms on species that grow between the shoreline and 3 meter of depth (on Chara aspera, Chara vulgaris, Chara hispida and Nitella hyalina). At higher depths (between 10 and 20 meter of depth) I generally found cyanobacteria of Nostoc genus and freshwater sponges (on Nitella opaca and Chara globularis).

Probably there are few studies about epiphytes on stoneworts, but they are common. 

Moreover... are you sure that the Chara in the picture is Chara aspera? It is very similar to Chara vulgaris.

Best regards

Mattia

Although charophytes are known as inhibitors of filamentous algae, very often we see them covered by epiphytes. Such a phenomenon I have seen in species of 5 genera: Chara, Lychnothamnus, Nitella, Nitellopsis and Tolypella. This applies mainly shallow sites, where sometimes filamentous algae can displace charophytes (see attachemnt - Chara aspera stand covered by algae). At deeper sites (where is less light - which does not bother charophytes but limits the filamentous algae) charophytes are much less (or et all) covered by epiphytes.

Best regards,

Andrzej

Charophytes are oftten covered with green filamentous algae. This specimen is collected from brackish sea. We (as a colleague of Priit) have not noticed red algae as an epiphyte on charas before.

After a quick search I found mention to epibionts (chironomid larvae) in a recent paper:

"Spatial distribution of epiphytic chironomid larvae in a shallow macrophyte-dominated lake: effect of macrophyte species and food resources", by M. Tarkowska-Kukuryk, in LIMNOLOGY 15 (2):141-153, from APR 2014.

I do not like the term "epiphyte", since the "-phyte" may refer to the basibiont (in your case, Chara) or the epibiont, leading to some confusion.

Hi! Maybe a late answer. I have observed Ceramium tenuicorne on Chara baltica in the Baltic Sea on a number of occasions. Although not explicitly stated, some information can be found in Mar Biol (2010) 157:2143–215. Best regards!

Sometimes epiphytes could be luxuriant on Chara, especially in autumn at high concentrations of biogens. Please find in attachment photo of Chara aspera completely covered with diatoms in north Kazakhstan lake. 

The old specimen of Chara aspera with epiphytic brackish-water rhodophytes from Baltic Sea was reported in https://www.researchgate.net/publication/265173011_2303_Proposal_to_conserve_the_name_Chara_hispida_Characeae_with_a_conserved_type

Article (2303) Proposal to conserve the name Chara hispida (Characea...

Roman, thank you very much for the references and nice picture

Best regards

Priit