Talk:Tepal

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Why did you delete the section on merosity? The article is (without it) only a definition and should be ported over to Wikipedia, but serves the purpose here of having an article on the perianth parts - Marshman 00:54, 4 February 2006 (UTC)

This article seems to be misleading. It starts by suggesting that tepals are peculiar to the Magnoliaceae, which is incorrect. I will make changes now so that it is roughly in line with what other sources agree a tepal to be, but please could someone who knows more about the subject sort it out? Thanks. Owl 14:39, 16 December 2006 (UTC)

OK, further to my last post, I've had a look at the history, and I propose reverting the article to its version on the 1st of December (http://en.wikipedia.org/w/index.php?title=Tepal&oldid=91340499). I will post on Hardyplants' talk page to ask him about his sources. If no-one disagrees, I shall make the revert in a couple of days. Owl 14:50, 16 December 2006 (UTC)

"In a general sense, a tepal is an element of the perianth of a flower, such as a petal or sepal. The perianth comprises the outer, sterile whorls of a flower. The term tepal is usually used when all segments of a perianth are of similar shape and color (that is, undifferentiated). This happens in the family Magnoliaceae and a number of other primitive flowering plants such as the Amborellaceae and Calycanthaceae."

Tepals are petals and sepals, there are other organs in the perianth that can be modified to look like petals, like stamens Note modern rose hybrids and Peonies). tepal is used for more than primitive plants, Hosta and many other genera have tepals, which are the result of the modification of the sepals. (Previous two paragraphs added: 19:14, 16 December 2006 Hardyplants)

Thanks, Hardyplants, for having another go at editing it. I still don't think it is clear, however. I will try editing it myself, and see what people think. Owl 14:54, 17 December 2006 (UTC)

Removed list of pubescence types[edit]

I've removed a section that listed "properties" of tepals, those having to do with short, downy, hairs. If we include that sort of material here, the list would need to include all the shape, size, colour, texture, terms from Glossary of botanical terms (even those for smell), which would be a very long list: villous, villose, glandulate, equal, subequal, verrucose, glabrous, subglabrous, narrow, broad, oblong, spathulate, lanceolate, linear, obovate, ovate, triangular, deltoid, attenuate, mucronate, aristate, pungent … Sminthopsis84 (talk) 19:31, 21 January 2014 (UTC)

Well maybe we should - at least those terms used to describe tepals on other pages pages. It is a lot easier for me to describe those on this page for once as terms appear and link tepal in descriptions to here, than have to explain them on every page. So consider for instance for comparison Leaf. So to be consistent I am putting them back, as a start for a tepal glossary. --Michael Goodyear (talk) 04:07, 22 January 2014 (UTC)
I have to say that I agree with Sminthopsis84. There might be some point in having here terms only used with tepals (if there are any) but general terms for shape, size, texture, etc. which are used for other parts of plants don't belong here. If in an article a tepal is described as "villose" or "mucronate", then link to the general definition if you feel it's needed. Peter coxhead (talk) 14:55, 23 January 2014 (UTC)
Since this is a generic issue, I have raised it on the WikiProject Plants talk page. --Michael Goodyear (talk) 14:28, 25 February 2014 (UTC)
I agree that the material in the properties section should be removed, as it's not specific to tepals. Lavateraguy (talk) 15:40, 25 February 2014 (UTC)
Did any resolution come from the discussions elsewhere? I haven't seen one. Sminthopsis84 (talk) 12:03, 23 March 2014 (UTC)

Opening paragraph of article[edit]

Quoting: "A tepal is a part of the outer part of a flower (the perianth) in which the petals and sepals are of similar shape and color, or undifferentiated, and therefore cannot be easily distinguished from one another. When different types of organs can be distinguished, they are referred to as sepals and petals. "

Question - when petals and sepals CAN be distinguished from one another, are they still collectively correctly called tepals? (I note at the end of the lead that "Usage of the term 'tepal' is inconsistent". Is there a "correct" version of the terminology?)

Other question - were the terms petal, sepal, and tepal deliberately chosen to be as confusing as possible?

Thanks, C7nel (talk) 16:15, 30 July 2014 (UTC)

When they can be distinguished, petals and sepals will usually be referred to separately, but can also optionally be referred to as tepals if there is doubt, or if no distinction is being made. See the definitions in Glossary of botanical terms. And no, the terms were not chosen to confuse but because of a need to to elucidate, or at least to avoid error. The natural world is sometimes more complicated than can be described in simple terms. Plantsurfer (talk) 18:58, 30 July 2014 (UTC)
But it has to be said that botanists, who used their form of Latin long after other scientists had abandoned the language, do seem to like complex terminology. To be a professional, for example, never write "bell-shaped" or "spear-shaped" – use "campanulate" and "hastate" respectively. Even "tepal" sounds a bit simple, so use "perianth segment" instead. :-) Peter coxhead (talk) 19:54, 30 July 2014 (UTC)
More seriously, this sentence A tepal is a part of the outer part of a flower (the perianth) in which the petals and sepals are of similar shape and color, or undifferentiated, and therefore cannot be easily distinguished from one another doesn't seem quite right to me. Magnolia flowers don't have distinct "sepals" and "petals". Also part of the outer part is ugly. Perhaps:
Tepal is the term used to describe one of the outer parts of a flower (the perianth) when these parts cannot be easily divided into two kinds, sepals and petals. This may be because the parts of the perianth are undifferentiated (as in Magnolia) or because although it is possible to distinguish an outer whorl of sepals from an inner whorl of petals, the sepals and petals are similar to one another (as in Tulipa).
Comments? Improvements? Peter coxhead (talk) 20:08, 30 July 2014 (UTC)
certainly an improvement. Plantsurfer (talk) 20:39, 30 July 2014 (UTC)
In the suggested rewording, perhaps "to identify" would be better than "to describe".
Thank you both. (When I suggested that petal, sepal, and tepal were perhaps deliberately chosen to be confusing, it was not to question the need for three different words to identify these plant parts. Rather that the three words seem to me to be confusingly similar. I.e., if another part of the perianth was now discovered and needed a name, would it be the pesal, the setal, or the tesal?) C7nel (talk) 21:41, 30 July 2014 (UTC)
The word was coined almost 200 years ago in 1827 by the Swiss botanist/taxonomist Augustin Pyramus de Candolle (1778–1841), almost certainly as a deliberate conflation of the words petal and sepal. Plantsurfer (talk) 23:01, 30 July 2014 (UTC)
Where perianth is differentiated into two distinct whorls, the outer whorl is of sepals and the inner of petals. Where the perianth is undifferentiated it may be known as the perigone and its parts as tepals. In angiosperms with more than two whorls the transition between sepaloid and petaloid leaves may be gradual, with indistinct boundaries, and the boundaries between petaloid tepals and stamens may also be indistinct. Plantsurfer (talk) 23:12, 30 July 2014 (UTC)

Petalness and Sepalness[edit]

I notice the Magnolia article says: "Magnolia shares the tepal characteristic with several other flowering plants near the base of the flowering plant lineage such as Amborella and Nymphaea (as well as with many more recently derived plants such as Lilium)."

Our article says: "In some plants the flowers have no petals, and all the tepals are sepals modified to look like petals." (The example is Hellebore).

So in the case of Hellebore, even though the parts look like petals, we know that they are not petals. And we know this how? (I'm not trying to be argumentative, just to comprehend.)

Is the case of the Magnolia fundamentally different that that of the Hellebore? Thanks, C7nel (talk) 14:34, 31 July 2014 (UTC)

I don't think the interpretations are correct; and what is "the tepal characteristic"? The various taxa listed have very different flower structures. This is how Ronse de Craene describes flowers of Magnoliaceae: "The perianth is usually trimerous and differentiated in an outer whorl of three tepals (sepals) and an inner part of two trimerous (petal) whorls...." In Nymphaea "The perianth is weakly differentiated into sepals and petals, although the distinction is unclear. The outer petals alternate with sepals in all genera . . .". In Hellebores, the petaloid tepals are not in clear whorls - Ranunculaceae have whorled and spiral flowers and transitional forms. In most Liliaceae there is no differentiation between the outer and inner whorl of tepals. They are both petaloid. Points of thhis are 1) it is wrong to lump them all together - there are very distinct differences in flower structure between species where the use of the word tepal is apporpriate. 2) use of the word tepal and petal can be interchangeable and optional, perhaps influenced by context, as in Ronse de Craene's description of Magnoliaceae, 3) the two whorls of tepals can be identified as sepals or petals from their position, if not always from their colour or form if presented out of context. 4) in plants with spirally-arranged flower parts, the tepals may look petaloid but there are not distinct whorls of petals and sepals. Plantsurfer (talk) 18:52, 31 July 2014 (UTC)
I think the most common use of "tepal" is in relation to the petaloid monocots, where it's straightforward to distinguish the three outer sepals from the three inner petals, but they look very similar. I don't think it's true that "[i]n most Liliaceae there is no [my emphasis] differentiation between the outer and inner whorl of tepals". The three sepals form the external surface of the bud; the three petals are completely enclosed inside them at this stage (at least in all the Liliaceae I know). However when the flower is fully developed, the sepals are "petaloid", i.e. similar in size, colour and function to the petals. There's quite good agreement between sources that I've looked at in these cases.
Magnoliaceae and the like are described much less consistently by different sources. Dandy in Heywood Flowering Plants of the World says of Magnoliaceae: "The perianth is composed of two or more (usually three) whorls of free tepals which are petaloid; the outer tepals are sometimes reduced and sepal-like." Thus he never calls the perianth segments either "sepals" or "petals", only noting that some tepals are petaloid and some sepal-like. In the same volume, Bramwell in describing the Monimiaceae (which is where Amborella was then placed) never uses the word "tepal", instead referring to the perianth "segments" being either "sepal-like" or "petal-like". Thorne says of the Winteraceae that "the sepals and petals are mildly differentiated", never using the word "tepal". I could go on with such examples! Basically the accounts of the "primitive" families in Heywood written by different botanists use different terminology. Peter coxhead (talk) 22:11, 31 July 2014 (UTC)