Resumos Biblio Fitolitos

7/27/2019 Resumos Biblio Fitolitos

1/9

362 AMERICAN ANTIQUITY [Vol. 49, No. 2,1984]

A Comparison and Differentiation of Phytoliths from Maize and Wild

Grasses: Use of Morphological Criteria

Author(s): Dolores R. Piperno

Cross-shaped phytoliths, which occur only in the Panicoid sub-family of grasses and

bamboos, were intensively evaluated because work by Pearsall (1978, 1979) and myself (1979,

1980) had indicated that they were most useful for distinguishing maize. (p.362)

In a study of phytolith size in Ecuadorian grasses, Pearsall (1978, 1979) showed that

cross-shaped phytoliths from maize were significantly larger than those of the native Panicoid

grass cover. Cross-shaped phytoliths were defined as those with at least three indentations

which have a dimension that falls between N by N and N by (N plus 2), with each micrometerunit (N) representing 4.58 microns. The expression N by (N plus 2) signifies that phytoliths more

than 9.16 microns longer than wide are not classified as cross-shapes. This distinction is useful,

because it eliminates phytoliths that appear to be transitional between dumbbells and cross-

shapes, and thus tightly defines the cross-shaped type. (p.362)

The combination of cross-shaped phytolith size and cross-shaped phytolith three-

dimensional structure securely separated all wild grasses, including teosinte, from many of the

maize races that were studied. Short-cell three-dimensional structure is also a highly promising

area for the identification of some genera and species of wild Panicoid grasses and bamboos.(p.380)

Journal of Archaeological Science (1984) 11, 345-368

Prospects and Limits of a Phytolith Key for

Grasses in the Central United States

Dwight A. Brown

Ratios of certain trapezoid shapes to saddles or bilobates can provide information on

the relative dominance of grasses possessing C4 and C3 carbon pathways. Fluctuations in

these ratios found in stratified deposits may reflect shifts in midsummer temperature through

time, but there are several sources of error that must be examined separately. Phytoliths that fit

in the festucoid class of Twiss et al. (1969) (now Pooicoideae) have been seen in the tribes

Aristideae, Eragrosteae, and Andropogoneae. Saddle shapes of Eragrosteae and Chlorideae

are also common in Phragmites australis and bilobates (dumbbells) of the Panicoideae

subfamily occur in species of Danthonia. (p.345)

In summary, there are sufficient differences among the most important taxonomic

groups in the central North American grasslands to allow us to identify the time of taxa arrival


2/9

during the Holocene, if stratified and datable deposits are available. Thus, it is possible for

phytolith analysis to provide a better understanding of migration rates and sources of major

species. (p.345)

A summary of the general phytolith shape characteristics for subfamilies and tribes of

grasses is shown in Table 6. The lack of both bilobates and saddles in the subfamily Pooideaeis important. Paucity of these two phytolith shapes in earth materials, coupled with the

abundance of trapezoids, probably indicates a dominance of C3 grasses. ()Variations within

subfamilies and tribes in the degree of importance of these shapes may also be significant, but

differences are not easily analyzed at this taxonomic level. (p.366)

Quaternary International 193 (2009) 8089

Phytolith analysis of Chusquea ramosissima Lindm. (Poaceae: Bambusoideae)

and associated soils

La Montti, Mariana Fernandez Honaine, Margarita Osterrieth, Dalva Graciano Ribeiro.

Leaves- The panicoid dumb-bells(bilobate flat/concave ends shortcell phytoliths) were the

second most abundant morphotype(Table3). They represent thesilica cells located in the costal zone of the

epidermis. Chusquea bulliform phytoliths(cubic/parallepipedal sinuate bulliform cells) were abundant, both

isolated or in articulated form. In a smaller proportion, the phytolith assemblage was characterized by the

presence of saddles and tabular crenate phytoliths. These phytolith morphotypes correspond to the

vertical silica bodies and long rectangular epidermic cells of winding walls of the costal and intercostal

zone, respectively. Silicification of hairs was also observed. Within the articulated phytoliths, fragments

formed by several of the morphotypes previously mentioned, were observed. (p.83).

In leaves, the main phytolith morphotypes described (concave dumb-bells, panicoid dumb-bell

sand Chusquea bulliform) are the same as the ones observed by Piperno (1988) and Piperno and

Pearsall(1998) for other species of the same genus or for other tropical bamboos. These authors argue

that these phytolith can be diagnostic of Bambusoideae subfamily. (p.87)

Soi l phytol i th assemblage- The dominant phytolith morphotype sinall the samples were the

concave dumb-bell phytoliths, except in the second sample of the Iguazu National Park close canopy

(NPc2 sample),where the greater proportion of phytoliths were rectangular smooth(o30 m long),probably

broken phytoliths, and degraded irregular phytoliths, possibly originated in trees or other dicotyledons

species. The second dominant morphotype was the panicoid dumb-bells, while the Chusquea bulliform

phytoliths predominate in some samples of gaps. (p.85)


3/9

Pl Syst Evol 270: 123 (2008)

DOI 10.1007/s00606-007-0597-z

Printed in The Netherlands

Diversity of lobate phytoliths in grass leaves from the Sahel region,

West Tropical Africa: Tribe Paniceae

A. G. Fahmy

The subfamily Panicolideae is characterized by the presence of bilobate, polylobate and

quadra-lobate phytoliths and absence of saddle phytoliths. (p.18)

The subfamily Panicolideae is characterized by the presence of bilobate, polylobate and

quadra-lobate phytoliths and absence of saddle phytoliths. Festucoideae produces orbicular

and sinuous types while Chloridoideae yields saddles (Twiss et al. 1969, Mulholland 1989,

Fearn 1998, Lu and Liu 2003, Gallego and Distel 2004).

Bilobate and quadra-lobate shaped phytoliths signify subfamily Panicoideae, which

includes tribes: Andropogoneae, Paniceae, Maydeae, Isachneae and Oryzeae (Twiss et al.

1969, Pearsall 2000). Piperno and Pearsall (1998) concluded that the bilobate-shape silica-

bodies are recorded from certain genera in other subfamilies, such as Aristida (Arundinoideae),

Eragrostis (Chloridoideae) and Stipa (Pooideae). (p.18)

Modern Phytolith Assemblages from the North American Great Plains

Author(s): Glen G. Fredlund and Larry T. Tieszen

Source: Journal of Biogeography, Vol. 21, No. 3 (May, 1994), pp. 321-335

Published by: Blackwell Publishing

Stable URL: http://www.jstor.org/stable/2845533 .Accessed: 30/07/2011 09:47

characteristic of the Stipa-type is that the smaller 'top' (typically the adaxial) surface

is flat, lacking any ridges or other secondary facets (Mulholland, 1989:497). Panicoid grasses

do produce small numbers of the Stipa-type. Con- versely, Stipa grasses commonly produce

Lobate (or Dumb-bell) forms. While the distinction is not taxonomi- cally perfect, this use of the

Stipa-type in classification should provide a means for distinguishing assemblages for Stipa-

dominated grasslands from Panicoid-dominated com- munities. Four morphotypes typical of

Panicoideae grasses are recognized in this study: Simple Lobate, Panicoid-type, Cross and

Other Lobate form. (p.325 326)

Saddles are abundantly produced by most genera within the Chloridoid tribe, especially

Bouteloua and Bouchloe which dominate the short-grass prairies of the Great Plains (Metcalfe,1960; Twiss et al., 1969; Mulholland, 1989). (327)


4/9

Conicals are roughly circular or oval in abaxialladaxial outline and exhibit a distinctly

asymmetrical cross-section. Conicals include all conical and truncated conical short-cell forms,

except those defined as Keeled below. Conicals are essentially the same as the 'Rondel' type

(Mulholland, 1989:495). Conicals are commonly produced by Pooideae grasses including Poa,Festuca, Agropyron; all of which are common native C3 grasses (Twiss et al., 1969; Brown,

1984; Twiss, 1992). Although this form is produced pre- dominantly by the common C3 grasses,

essentially all grass subfamilies produce trace amounts of this general morphotype

(Mulholland, 1989). (p.324)

Diversity and Distributions (2003) 9, 7387

BlackwellScience, LdMorphological variations of lobate phytoliths from grasses in

China and the south-eastern United StatesHOUYUAN LU and KAM-BIU LIU

Early phytolith researchers noted that the different subfamilies of grasses produce

different phytolith shapes; for example, grasses of the subfamily Panicoideae produce dumbbell

and cross-shaped phytoliths, whereas Pooideae (Festucoideae) grasses produce rondels and

sinuous types, and Chloridoideae grasses produce saddleshaped phytoliths (Twiss et al., 1969).

All members of the grass subfamilies Panicoideae and Oryzoideae produce the bilobate

(dumbbell) type of phytoliths. However, bilobate (dumbbell) phytoliths, thought previously to be

the most diagnostic marker of the Panicoideae subfamily (Twiss et al., 1969), are also present

in the Chloridoideae and Arundinoideae subfamilies (Mulholland, 1989; Lu, 1998; Piperno &

Pearsall,

1998; Lu & Liu, in prep.). (p.74)

Lobate phytoliths are originated from the short cells of grasses with identifiable shape

characteristics. Metcalfe (1960) identified three types of dumbbell or bilobate phytoliths. The

Panicoid division in Twisss classification is composed of 11 types of dumbbells and crosses

(Twiss et al., 1969). Brown (1984) recognized bilobates, polylobates and crosses. Mulholland &

Rapp (1992) proposed the lobate class to denote phytoliths with definite lobes, including the

cross, sinuate and dumbbell types. Based on our observation and statistics of the lobate

phytoliths from 85 species of modern grass plants, we found that two important parameters can

be used to characterize the morphological variations in lobate phytoliths: (1) the shape of the

outer margins of the two lobes and (2) the length of the shank in the lobate structure. (p.78)

Panicoideae produces dumbbell and cross-shaped phytoliths; Festucoid forms rondels

and sinuous types, and Chloridoideae yields saddles (Brown, 1984; Mulholland, 1989; Fearn,1998). The shape of individual phytoliths


5/9

from grasses can be used as an indication of C3 or C4 photosynthetic pathways. (p.84)

Journal of Archaeological Science 1989,16,489-5 11

Phytolith Shape Frequencies in North Dakota

Grasses: A Comparison to General Patterns

Susan C. Mulholland

Dumb-bells and crosses were identified as characteristic of the Panicoideae; they are

described as halter-shaped. (p. 491)

Saddles were found in four species of the Chlorideae (Chloridoideae), but a bamboo

(Bambusoideae) also contained saddles. Dumb-bells and crosses were observed in all Panicoid

species examined but also occurred in Aristida, a non-Panicoid. Hilaria, which produced dumb-

bells, was then classified as a Panicoid and did fit the pattern; it has since been reclassified as a

Chloridoid (Pohl, 1978), becoming an anomaly. Although the correlation of the three subfamilies

to three phytolith shapes may hold in general, exceptions do occur. Twiss et al. (1969: 112)

concluded that phytolith morphology and grass taxa must be correlated cautiously. (p. 492)

Trapezoids occur in many Chloridoid species; dumb-bells were found in some species.

(p.492)

The three major classifications of grass silica-cells identify similar shape types. Twiss etal. (1969) proposed three major divisions: dumb-bell/cross (Panicoid), saddle (Chloridoid), and

rectangular/oblong/circular (Festucoid). Most of Metcalfes (1960) 20 shapes can fit with these

divisions. He recognizes dumb-bells, crosses, and saddles, as well as other shapes that appear

similar to Festucoid types. Brown (1984) also distinguishes crosses, dumb -bells (bilobates and

polylobates), saddles, and other forms (trapezoids). Based on illustrations and descriptions in

this literature, the following correlations can be made between classifications. (p. 495)

The Panicoideae are dominated by dumb-bells and crosses, whereas the Chloridoideae

have saddles and saddle-like dumb-bells and crosses. Most deviations from these patterns are

less than 5% of the assemblage. Saddles occur regularly as a minor component of Pooids.

Sinuates are not unique to the Pooideae; minor amounts are present in three species of other

subfamilies. (p. 497)

()rondels occur frequently in subfamilies other than the Pooideae. Rondels, sinuates,

and rectangles had been thought indicative of this subfamily. ()enough occur elsewhere so

that rondels in sediments cannot be automatically attributed to the Pooideae. However, sinuates

and rectangles are largely confined to the Pooideae. (p. 497-498)

Chloridoid inflorescences are dominated by saddles to an even greater extent than seen

in the leaf. ()Panicoid inflorescences generally continue a trend of dominant dumb -bells andcrosses; however, dumb-bells decrease with respect to other forms. (p. 498)


6/9

Most sinuates, rectangles, and rondels occur in the Pooideae; saddles dominate the

Chloridoideae; and the Panicoideae contain abundant dumb-bells and crosses. (p.499)

The Panicoideae have long been characterized by dumb-bells and crosses [Table 1

l(a)]. Twiss et al. (1969) indicated occurrence in all Panicoid species examined. Brown (1984)

found dumb-bells in all but one of his Panicoids (Panicum obtusum). Metcalfe (1960) recordeddumb-bells and crosses consistently in the Panicoideae, although Capillipedium (Andropogon

venustus) lacks any of these forms. Gould & Shaw (1983) also indicated that the Panicoideae

produce dumb-bells and crosses. (p.506)

However, dumb-bells are not restricted to the Panicoideae [Table 10(b)]. Twiss et al.

(1969) found them in a Chloridoid (Hilaria) and an Arundinoid (Aristida). Brown (1984) also

recorded them in Chloridoids (Eragrosteae) and Arundinoids (Danthonia and Aristida). Metcalfe

(1960) found dumb-bell and cross forms in the Arundinoids (Danthonia, Arundo, Aristida),

Chloridoids (Diarrhena, Uniola, Eragrostis, Muhlenbergia, Enneapogonf, and four Pooids

(Phalaris, Calamagrostis, and two Stipoids). Gould & Shaw (1983) recorded dumb-bells in four

tribes of the Gramineae (Stipeae, Brachyelytreae, Nardeae, and Monermeae) as well as

Arundinoids and Chloridoids. ()This study indicates that Chloridoid dumb-bells may possess a

distinctive three-dimensional morphology, resembling saddles. Stipoid dumb-bells may also be

distinguishable from typical Panicoid dumb-bells, although the morphology is not as distinct. In

addition, Aristida may contain dumb-bells with longer shafts than in Panicoids. (p. 506)

Annals of Botany 98: 11551165, 2006doi:10.1093/aob/mcl207, available online at www.aob.oxfordjournals.org

Phytolith Assemblages and Systematic Associations in Grassland

Species of the South-Eastern Pampean Plains, Argentina

MARIANA FERNNDEZ HONAINE,ALEJANDRO F. ZUCOL

and MARGARITA L. OSTERRIETH

The phytolith assemblages of the subfamily Panicoideae show two tendencies: the first

characterizes the panicoid species (Paspalum quadrifarium) and is dominated by the presence

of short-shank, convex-ended dumb-bells; the other is present in andropogonoid species

(Sorghastrum pellitum and Bothriochloa laguroides) and is characterized by short-shank,

concave/straight-ended dumb-bells. (p. 1160)

Short-shank, convex-ended dumb-bells not only characterize species of the

Panicoideae subfamilies, and therefore mostly of C4 species, but are also present in species of

the Pooideae (Melica brasiliana). (p. 1161)


7/9

Estuarine, Coastal and Shelf Science 58 (2003) 587600

Phytoliths of common grasses in the coastal environments of

southeastern USA

Houyuan Lu, Kam-biu Liu

The dumbbell (lobate) phytolith originates from the epidermal cells (shortcells) of

Panicoideae and Oryzoideae, some Arundinoideae, and Chloridoideae subfamilies. (p. 588)

The Chloridoid class (Twiss et al., 1969) consists of only two types of saddle-shaped

bodies; one is the Chloridoid type (which originates from epidermal cells (short cells) of

Chloridoideae, and some Bambusoideae and Arundinoideae subfamilies. (p. 588)

The Festucoid class (Twiss et al., 1969) contains several geometrical types that arecircular, rectangular, elliptical, or oblong. Kondo et al. (1994) and Pearsall (1989) used the

same term of Festucoid class to define the short-cell phytolith types as originating from the

epidermal cells of the Pooideae subfamily. (p. 588)

All specimens of plants from Panicoideae (Fig. 1 and Plate 1A, D) and Oryzoideae

(Plate 1B) grasses in this study have typical dumbbell type. The crosses are mostly associated

with the Panicoideae subfamily. Despite being the most characteristic markers of the

Panicoideae (Twiss et al., 1969), dumbbell and cross phytoliths are also found to be present in

the Chloridoideae (Aristida desmantha and Ctenium aromaticum). (p. 593)

The short saddle morpho-type is produced in a high proportion by the Chloridoideae.

The descriptive term, _battle-axes with double edges_ (Prat, 1936), refers to the outline of the

base when the body is oriented in top view. Saddle-shaped phytoliths are the dominant class of

the Chloridoideae subfamily. (p. 594)

A great quantity of _rondel/saddle ellipsoid_ morphotypes are isolated from Spartina

alterniflora (Chloridoideae), with both round and saddle tendencies. Spartina alterniflora

(cordgrass) is a tall, stiff-stemmed grass typically growing in salt marshes. (p.595)

Rondels (circular to oval phytoliths) and wavy trapezoids (Mulholland, 1989) are most

closely associated with Pooideae. Wavy trapezoid (Plate 3B), in particular, appears to be

unique to Pooideae. (p. 597)

Journal ofArchaeologicalScience37(2010)1953e1967

Poaceae phytolithsfromtheNiassaRift,Mozambique

Julio Mercader , FernandoAstudillo , Mary Barkworth , Tim Bennett , Chris Esselmont ,

Rahab Kinyanjui , Dyan Laskin Grossman , Steven Simpson , Dale Walde

We also document polylobates, which are frequent in the Panicoideae. (p. 1965)


8/9


9/9

of saddle-, bilobate-, and rondel-like siliceous bodies, with forms assuming traits

intermediate between these major classes also being common. Most regular saddles were tall. Leaf

epidermal silicifications that result in a dominance of planar, mirror-image saddles and bilobates

characteristic of mainstream genera in the Chloridoideae and Panicoideae appear to be later

developments. It also can be argued that chloridoid ancestors had leaf epidermes with bilobate silica

bodies and that panicoid ancestors had leaf epidennes with saddle-shaped silica bodies. (p.7)

Reprinted from the Soil Science Society of America Proceedings

Vol. 33, no. 1, January-February 1969

677 South Segoe Road, Madison, Wisconsin 53711 USA

Purchased by Agricultural Research Service, U. S. Department of Agriculture, for

official use.Morphological Classification of Grass Phytoliths

P. C. Twiss, ERWIN SUESS, AND R. M. SMITH

The Chloridoid class contains two types of saddle-shaped bodies. The Panicoid class

contains 11 types that are variations of crosses and dumbbells. (p.109)

The Chloridoid class (Class 2) consists of only two types of saddle-shaped bodies. Prat

(21) described them as "battle axes with double edges" and designated them as a type in the

subfamily Panicoideae. (p.111)

Resumos Biblio Fitolitos

Documents

Transcript of Resumos Biblio Fitolitos