[miremonster]

Hello,

some of the fern species which are the closest relatives of Microsorum pteropus could be interesting for submerged cultivation, judging from informations of their natural habitats in SE-Asia (growing on stones and boulders in and on streams, some are stated explicitly as rheophytes):

- Microsorum insigne (with M. dilatatum and M. hancockii)
- species, varieties and forms of Colysis (Leptochilus), e.g. L. macrophyllus var. fluviatilis, L. minor

I've got Colysis wrightii (= Leptochilus macrophyllus var. wrightii) from the Botanical Garden of Halle/S. (Germany) and as an experiment I've put it in a tank a few days ago .

Has anybody of You experiences with these ferns?

Greets
Heiko

 

[rs79]

So what happened with these?

 

[rs79]

FWIW it's worth, one of these is available here for $15.

http://www.blackjungle.com/Merchant...t_Code=F-MS1&Category_Code=FM&Store_Code=BJTS

Looks like java fern to me. My totally uninformed guess is java fern grows better subnersed.

 

[miremonster]

Hello rs79,

this looks like Microsorum linguiforme. Its venation is similar to that of M. pteropus, but M. linguiforme, an epiphyte or lithophyte, is not closer related to M. pteropus.

Colysis wrightii (= Leptochilus macrophyllus var. wrightii): It grew submersed for several months on a lava stone in my tank indeed, but I can't designate it as a good aquarium plant. While the grow rate was similar to M. pteropus, new submersed leaves were pale green and smaller than the emersed ones:

Some got brown and deformed:

The plant was prone to algae growth more than some forms of M. pteropus growing close to the C. wrightii.
Both terrestrial and submersed leaves of this fern are much stiffer than these of M. pteropus.
Now it grows as a terrestrial plant again in a mini-"greenhouse" on the windowsill.

According to H. P. Nooteboom (The Microsoroid Ferns, Blumea 42 (1997), 261-395), Colysis wrightii doesn't occur especially on or in waters. But there are interesting informations in this paper about the ecology of other Colysis (Leptochilus) taxa:
- Leptochilus macrophyllus var. fluviatilis (Colysis fluviatilis, Polypodium linealifolium), Borneo, Philippines, Sulu Archip., New Guinea: a rheophyte, "On rocks in and by streams, often submerged".
- L. macrophyllus var. pedunculatus (C. pedunculata, C. membranacea): "Epiphytic and epilithic, on boulders by streams".
- L. macrophyllus var. macrophyllus (C. macrophylla etc.): "Terrestrial and on rocks by streams..., usually in wet places."
- L. minor (Colysis minor, Gymnopteris metallica etc.), India, Sri Lanka, Vietnam, Thailand, Sumatra, Borneo, Sulawesi, Philippines : "Terrestrial, often on rocks in stream along water level", "Some forms possess a metallic blue tint when alive... . This metallic tint may be induced by the rheophytic habitat."
- L. hemionitideus (C. hemionitidea), S-China, NE-India, Nepal, Sikkim, Bhutan, Thailand: "Terrestrial on stones in stream, ..., on wet ground in streambed in dense forest, locally common."

Bye
Heiko

 

[miremonster]

I've found some pics of Leptochilus:

L. macrophyllus var. fluviatilis. According to habitat informations this fern seems to grow at similar sites like Microsorum pteropus. Leaves with sporangiums are narrower and have longer leaf stalks than sterile leaves.
http://picasaweb.google.com/barceljf/PhilippineFernsAndFernAllies/photo#5099259942803767826

Lower surface of a fertile leaf of L. macrophyllus var. fluviatilis:
http://picasaweb.google.com/barceljf/PhilippineFernsAndFernAllies/photo#5099264675857728034

L. macrophyllus var. macrophyllus:
http://picasaweb.google.com/barceljf/PhilippineFernsAndFernAllies/photo#5099264693037597234

Lower surface:
http://picasaweb.google.com/barceljf/PhilippineFernsAndFernAllies/photo#5099264710217466434

 

[miremonster]

Leptochilus hemionitideus (Colysis hemionitidea) is quite similar to Microsorum pteropus:
http://tpbg.tfri.gov.tw/Default.aspx?tabid=1007
http://www.thaifern.com/Polypodiaceae/colysis/hemionitidea.htm

These photos don't show Leptochilus minor but Microsorum pteropus:
http://www.thaifern.com/Polypodiaceae/Leptochilus/leptochirus-minor.htm

That's not Colysis simplicifrons but M. pteropus, too:
http://www.thaifern.com/Polypodiaceae/colysis/simplicifrons.htm

But this, labelled as M. pteropus, is apparently another fern species:
http://www.thaifern.com/Polypodiaceae/Microsorium/pteropus.htm

 

[miremonster]

One may wonder if this thread deals with Microsorum forms with very narrow strap-like leaves like Microsorum "Needle leaf", and if these belong to other species than M. pteropus. But there is evidence that they all are forms of M. pteropus (in the broader sense) indeed.
All Microsorum species but M. pteropus are not aquatic. But some Leptochilus/Colysis (and M. insigne?) are at least rheophytes (see above).

Bosman (1991) and Nooteboom (1997) synonymized several species names with M. (Bosman: Colysis) pteropus, e.g. M. brassii, M. zosteriforme, Drynaria dubia, D. tridactyla, M. udum, Polypodium aquaticum, P. micropteris, M. pteropus var. minor, etc.
These names partly refer to vouchers of plants that are smaller or narrower-leaved than typical M. pteropus.

Some characteristics of M. pteropus:
(microsoroid ferns = species that belong to microsorum and related genera)

- rhizome scales relatively narrow, slightly spreading (similar to the scales of Leptochilus/Colysis)

- scales on the midvein of leaves (lower surface) more or less persistent, often densely set, often with brown rhizoid-like hairs (most other microsoroid ferns: scales on midvein early shed when the leaf becomes mature)

- midvein not prominent on the upper but on the lower surface of the leaf

- lateral veins of the leaves forking near the leaf margin and connected by a distinct bow-shaped vein

- development of plantlets on the leaves (not reported from any other microsoroid fern species)

- thin-herbaceous texture of leaves (not thick or leathery).