Commelinidae

Commelinidae (in Spanish, "las commelínidas") is a taxon of plants located in the taxonomic category of subclass, used in systems of modern classifications such as the 2009 APG III classification system and by the APWeb (2001 onwards). In these classification systems, this taxon is located in the monocotyledonous clade (here located in the class category), and is circumscribed by the Arecales, Zingiberales, Commelinalales and Poales orders, and by the Dasypogonaceae family (which as of January 2011 still did not was assigned to no order).

The taxon as circumscribed here forms a monophyletic group well established both by morphological characters and by molecular DNA analyses, so its existence had long been suspected (but in other popular classification systems such as Cronquist's). of 1981, the constituency was different, approaching the one defined here Poales). One apparent chemical synapomorphy that unites the entire group is the presence of acids that fluoresce in ultraviolet light (including coumaric, ferulic, and diferulic acids). Commelinids include a number of economically important plants, including palms (family Arecaceae), ginger (family Zingiberaceae), banana (family Musaceae), and grasses and cereals (family Poaceae), among many others.

Description

Theoretical Introduction in Descriptive Terminology of Plants

Putative synapomorphies are anatomical, include Strelitzia type epicuticular waxes, starchy pollen, non-lignified cell walls, and impregnated with UV-fluorescent acidic compounds (ferulic, diferulic, and coumarics), and leaves with silica bodies (SiO₂ Dahlgren et al. 1985, Harley and Ferguson 1990, Barthlott and Fröhlich 1983, Harris and Hartley 1980, Zona 2001), also the para or tetracytic stomata, the bracteate inflorescence, the starchy pollen grains, and the short and wide embryo (APWeb).

Silica concentrations in this clade are generally high, though of course not in groups that do not have silica bodies, and even then they are not always high (Ma and Takahashi 2002).

In Poaceae and Arecaceae at least, lignins contain p-coumaryl alcohol ("p-coumaryl alcohol"), as well as coniferyl and sinapyl monomers (Siegler 1998).

While it is common to find vessels on the stem and leaves (Wagner 1977), it may be incorrect to treat them as a synapomorphy.

In the few commelinids in which floral development was studied in detail, the expression of the PISTILLATA orthologous function B gene seems to be restricted to the stamens and staminodes and to the petals (Adam et al. 2007), this may be related to the 2-whorl nature of the perianth found in many members of this clade. In some of the few other monocots studied, floral development may be somewhat different.

Starchy pollen is common, but it was not found in Hanguanaceae or Dasypogonaceae (only one species of the latter family was examined) or in some species of Haemodoraceae, Bromeliaceae, etc.

The broad embryos may be a synapomorphy of this clade.

Ecology

Nymphalidae-Morphinae and Satyrinae larvae have been found in this group (Ehrlich and Raven 1964), and also Chrysomelidae-Hispinae+Cassidinae (Jolivet 1988, Schmitt 1988, Vencl and Morton 1999, Chaboo 2007), but the latter have also been found in other monocots. Of the latter, 14/39 tribes were found for which there is at least one commelinid plant that is a host for their larvae, while 26/39 tribes were hosts for some other plant (Chaboo 2007; these larvae were also found in Boraginaceae, Solanaceae, Convolvulaceae and Asteraceae, in particular, in the nucleus of the eudicots —asterids seem to prevail—). It is not clear whether Criocerinae is in a clade immediately related to Hispinae and other related monocot-eating beetles (see Chaboo 2007; compare Wilf et al. 2000 and Gómez-Zurita et al. 2007).

Hemiptera-Lygaeidae-Blissinae larvae have been found to feed on the sap of (Zingiberales + Commelinales), although they are also found in other Poales, especially the Poaceae (Slater 1976).

Diversity

The taxonomic diversity of monocots is presented in detail by Kubitzki (1998, 2006).

A list of Commelinidae diversity is provided below. The descriptions are deliberately incomplete. For more information follow the links.

Habits of Kingia australis Dasipogonaceae Main article: Dasypogonaceae Dasipogonaceae are four genera of rhizomatous or arborescent plants (by primary thickening), with spiral leaves with well-developed vain and persistent bases, and dry perianto. They are distributed in Southwest Australia and Victoria.

Habitacion of a palm tree Arecáceas Main article: Arecaceae Arecáceas are easily recognizable, in general it corresponds to what people know as "palmeras". Almost all of them are arborescent (by primary thickening), with stem without branching, and have the pine or palm leaves arranged in a terminal rosette. Their flowers, with sepals and petals, are gathered in branched inflorescences protected by a woody spata. The palm trees are widely distributed but especially in warm regions. Arecaceae is one of the most economical plant families. Some examples are the coconut tree, the palm tree, the palm tree, the rattan, the palm tree from which the carnaúba wax, the rafia is extracted, and a large number of ornamental species. They also often have considerable ecological importance in the places where they settle.

Traveler tree habitat Zingiberales Main article: Zingiberales Zingiberales is a clay of eight families, among its members are the ginger, the butterfly flower, the wizard, the bird of paradise, the tree of the traveler and the banana. They are herbs (sometimes monster-sized, like Musa, Ravenala or Strelitzia), without aerial stems except the one that gives the flowers, with leaves clearly differentiated in petiole and foil, many times broken between the secondary veins, the bilateral flowers (but in more specialized nails without plane of symmetry), and the seeds with arilo. The families of this order are well known for the modifications of their androceum, so that what appears to be the perianto are often petaloid stamens, so flowers are usually difficult to interpret and the pieces are not always what they seem to be.

Bed room Commelinales Main article: Commelinales Commelinales is a line of five families, among its members are comelin, tradescantia, pontederia, and camalote. All families have an inflorescence that is a helicoid peak with many flowers. While Commelinales monophilia is well supported by molecular DNA analysis, its morphological synapomorphic synapomorphies are still discussed, being restricted to phytochemicals (such as the presence of phenylphenona) and some seed characters (such as the abundant helobial endosperma). Three of the five families of this clove are unique among the commelides for having tepaloid perianto, instead of sepals and petals.

Habits of Cyperus papyrus Poales Main article: Poales Poales is an important line of 18 families, among its members are the totora, the ananá, the key to the air, the papyrus, the cougars, the bamboo, the pastures and the cereals. The anemophilic pollination (by wind), with the loss of the septal necrotes, has often developed independently within the Poales.

Phylogeny

Theoretical Introduction in Philogenia

The group as circumscribed here is monophyletic on the basis of rbcL sequences (Chase et al. 1993, 1995b, Duvall et al. 1993), to rbcL and atpB sequences (Davis et al. 2004), to multi-region sequences of DNA (Chase et al. 2000, 2006, Graham et al. 2006, Soltis et al. 2000), and to the morphology (Dahlgren and Rasmussen 1983, Stevenson et al. 2000). See also Givnish et al. (1999).

Even before molecular DNA analyses, the existence of this clade was long suspected by some authors (Dahlgren et al. 1985) due to the number of characters that are present exclusively in these taxa, already stated in the characters section.

The cladogram updated to date, of the location of the clade within the monocots, and the relationships between its subclades, is as follows (updated according to APWeb as of January 2009):

The relationships between the main groups of commelinids are still unclear. Regarding which clade would be the basal one, DNA sequence analyzes (Chase et al. 1993, 1995b, 2000, Soltis et al. 2000) suggest that the palms are the sister group to the rest of the members of the clade: Poales, Commelinales, and Zingiberales. However, in other molecular analyzes (Chase et al. 2006, Graham et al. 2006) palms are nested within the commelinoid clade. Hilu et al. (2003), based on the matK sequence, suggested that Poales could be sister to the rest.

Dasypogonaceae was placed here on the basis of its characters matching those of the commelinid clade (Rudall and Chase 1996), although earlier authors associated them with other groups of xeromorphic monocots from Australia, such as Xanthorrhoeaceae (as in Dahlgren et al. 1985), due to their similarities in habit, or Laxmanniaceae (now Lomandroideae, formerly Lomandraceae) as in Takhtajan (1997). Neyland analyzing rDNA sequences (2002) found Dasypogonaceae strongly associated with Restionaceae and other Poales families, but this particular relationship is not suggested by other molecular data, nor does it appear in morphological analyses. However, recent work using gene pools does not associate it with Arecales either, and even when they do it is with low support (Givnish et al. 2006 and Chase et al. 2006 find it near Poales, Graham et al. 2006 find it near (Commelinales + Zingiberales)).

Arecales is sometimes listed as a brother to Poales (for example in Graham et al. 2006) but with very little support. Arecaceae have non-starchy endosperm, Dahlgren et al. (1985) suggest this may represent evolutionary loss. If palms are the basal clade of commelinids, the starchy endosperm may actually be a synapomorphy of the clade comprising the rest of the orders.

The possible morphological synapomorphies that would unite (Poales (Zingiberales + Commelinales)) would be the primary wall mainly with glucurono-arabinoxylans, the paracytic or tetracytic stomata, with neighboring cells with parallel cell divisions, and the endosperm with starch.

(Commelinales + Zingiberales) is a clade with strong support (100% support in the multigene analyzes of Chase et al. 2006 and Graham et al. 2006); although in previous studies this group had rather weak support (for example in Chase et al. 2000, in Davis et al. 2004, in Givnish et al. 2006 with a single gene). The morphological synapomorphies would be the indeterminate inflorescences, but with ramifications of helical cymes with many flowers and the invasive or plasmodial mat.

Cronquist (1981) found an important morphological similarity between Arecaceae and Pandanaceae/Cyclanthaceae (the latter two are now located in the Pandanales, outside the Commelinids). These three families, which Cronquist (1981) brought together with some others in the subclass Arecidae, share an arborescent or herbaceous vine-like habit, tetracytic stomata, indehiscent fleshy fruits, and similar embryo development. However, in Pandanaceae/Cyclanthaceae all other characters already mentioned as synapomorphies of the commelinoid clade are absent, so it is not surprising that they are not within it. This author associated Commelinidae with Zingiberidae, because they share their starchy endosperm, with compound starch grains, and their typically herbaceous perianth differentiated into sepals and petals, as opposed to the presence of tepals of their Liliidae circumscription. The other families that were indeed Commelinids but that Cronquist (1981) did not associate with Commelinidae/Zingiberidae were Dasypogonaceae, Hanguanaceae, Philydraceae, Pontederiaceae, and Haemodoraceae. The last three were considered members of the Liliidae because they have large tepals and look like lilies.

Taxonomy

Theoretical Introduction in Taxonomy

The subclass was recognized by the APG III (2009), the Linear APG III (2009) assigned it the family numbers 76 to 106. The orderThe subclass had already been recognized by the APG II (2003) which called it commelinids in English, without subclassing it.

The following orders are circumscribed in the clade, according to APG III and APWeb:

• Arecales
• Commelinales
• Poales
• Zingiberales

In addition, the family Dasypogonaceae is circumscribed within the clade, which at that date had not yet been identified as a member of any order.

Cronquist System

The older Cronquist system (1981) divided the subclass into seven orders:

Order Commelinales:

Xiridáceas, family Xyridaceae.

Commelinaceae, family Commelinaceae.

Order Hydatellales:

Hidateláceas, family Hydatellaceae.

Order Typhales:

Sparganiaceae.

Typhaceae.

Eriocaulales Order:

Eriocauláceas, family Eriocaulaceae.

Order Restionales:

Restionaceae, family Restionaceae.

Order Juncales:

Juncáceas, family Juncaceae.

Cyperal Order:

Cyperaceae, Cyperaceae family.

Gramíneas, family Poaceae.

The circumscription of Commelinidae according to Cronquist (1981) is close to the circumscription of Poales here, but without Bromeliaceae and with Commelinaceae (now in Commelinales) and Hydatellaceae (now in Nymphaeales). According to this author, Arecales was in the subclass Arecidae, which was not related to the Commelinidae/Zingiberidae.

Evolution

According to Janssen and Bremer (2004), the Commelinid stemgroup is dated to about 122 million years to the present, divergence within it would have started about 120 million years ago. According to Wikström et al. (2001), using a nonparametric rate smoothing approach from Sanderson (1997), the dates would be 107-98 million years. years for the stem group, and 99-91 million years for divergence if Arecaceae is sister to the rest, 94-86 million years if Dasypogonaceae is sister to the rest. According to Bremer (2000), the date of the stem group would be about 116 million years ago, Arecaceae and Dasypogonaceae diverging almost immediately after, and Poales and the clade (Commelinales + Zingiberales) would have diverged within 4 million years.

The rate of molecular evolution in this clade is generally high, about 0.003 substitutions/site/million years (Smith and Donoghue 2008). But for some genes, at least for ndhF, the rate of molecular evolution is similar to that found in Asparagales and other clades (Givnish et al. 2006). On the other hand, in Arecaceae the genes of the 3 genomic compartments evolve slowly (Wilson et al. 1990, Baker et al. 2000a, 2000b), but the The rate appears to be not much less than that found in some other monocots, especially when they are not commelinids (Graham et al. 2005). Stevens at APWeb wonders if there was an increase in the rate of molecular change within some Commelinids, some Poales being spectacular examples of this.

The stem group for the clade (Poales (Zingiberales + Commelinales)) would date to about 120 million years, and Poales would have diverged from the rest about 117 million years ago (Janssen and Bremer 2004).

The stem group of (Zingiberales + Commelinales) dates from about 116 million years to the present, the divergence of the two clades would have been about 114 million years ago (Janssen and Bremer 2004), but Wikström et al. (2001) indicate 87-83 and 81-73 million years respectively, and Kress and Specht (2006) indicate 124 and 110-80 million years respectively, and Bremer (2000), mainly with fossil calibrations, he dates them at 108 and 84 million years respectively.

Economic importance

The commelinids include a number of economically important families, including palms (Arecales), ginger and banana (Zingiberales), and grasses (Poaceae). In particular, the Poaceae family is perhaps the most important family of plants, since cereals are among them.