LATITUDINAL DISTRIBUTION OF ONYGENALES AND RELATED HYPHOMYCETES IN SOILS OF NORTHERN CHILE BE1WEEN 18-34° SOUTH LATIWDE

In the course of 1985 up to 1989, 332 soil samples were studied by using the keratinic bait technique. Qualitative and quantitative variations of the Onygeoales population and associated Hypho· mycetes ( 47 species) between urban-pcripheric and wild habitats of coastal and inland areas, in a latitudinal gradient ( 18-34!15) of the Chilean territory were explored. Highest iso/ates were found in urban-peripheric areas, being Chrysosporium, Aphanoascus, Mal· branchea, Trichophytoo and Gymooascus the dominan! genera. Ho/omorph taxa such as Aphanoascus fulvescens, A. keratioophilum, A. verrocosus, Arthroderma quadrifidum and Gymnoascus reesii were considered as euridominant because of their maintaining dominance and constancy in a/1 latitudes studied. At the same time, reproductive-multiplicative strategies of the community, their pattems of latitudinal distribution and the biogeography, associations of species, certain ecological parameters (Shannon-Weaver diversity and Pearson afftnity) were analyzed to finislt with the taxonomic comment and the present unstable nomenclature.


INTRODUCTION
The flora aod fauna exhibit distinct latitudinal gradients of distribulion which in ·the microscopic mycota of soils have been discussed in more detail since the second half of our century by using reasonable sampling methods (1,2, 3, 4, 5, 6, 7, 10. 26,44).
Upon analyzing the literature on taxon an orientation based mainly on a controversia! and confused taxonomic race that it reconfrrms only the known and old concept of heterogeneity of Onygenales and that of the taxonomists' opinion who study them is quite evident. (11, 12. 13. 14. 15, 16, l7. 18, 19, 20, 21, 22).
The vegetationaJ parameter is considered in the studies of the parasitic or symbiotic macrofungi as the substratum most frequently used by these organisms, with some exceptions. For this reason the autotrophic community reprcsents a more efficient and immcdiate source of environmental information than the study of soil, climate, geography or orography of the sampling zones. In the c.ase of saprotroph microfungi of tbe soil, somettmes the vegetational parameter, in spite of its imp?rtance, affords a restricted piece of infor-matlOn because of the presence in this habitat of different usable substrata. This is why the fauna (mesofauna included, 92) and the human population ~ensity allow also very useful information, due to 1ts close relationship with the scattering of viable propagules for new habitats. In these cases, the attempts to elucidate fungal functions by means of studies on pure cultures of the degrading abilitv of individual taxon are recommended to get som~ ecological conclusions (46,65).
The greal spatial varicly connected with the microfungi distribution is due to the fact tbat soil represents a mosaic of microhabitats for the developmém of microorganisms, which requires strict quantitative studies with the applications of statistical analyses to cxplain fungal distribution by means of biotic and abiotic variables and through direct or indirect sampling methods. However, it is not always easy to recognize the nature or the number of individuals in a particular place.
We do not know much yet about the function of their populations in the microbiota of tbe different telluric habitats and the composition of the structure of their communities, except that by mcans of sampling techniques with keratinic baits (hair and feathers), it is possible to detect their presence in many soils of tbe world, ranging from the richesr in organic nutrients to the poorest and most deserted ones. at different latitudes and heights. This asseverates the wide cosmopolitan distribution of their teleomorphs and anamorphs m~inly in soils containing a high humus contcnt, or ammal excrements (11. 23, 24, 25, 27, 28, 29, 30), but also on the hair and feathers of the former under every climate of the world (31,32,33,34).
Controversies seem to go on ·when we intend to apply to these fungi those theories or hypotheses aiming to explain· the variety of species in the community (time, competence, space heterogencity, climatic stability, etc.) where clear overlappings can be• seen; therefore, the abundance or rareness of species can be related to multiple edaphic factors (physical-chemical) or to another biotic or abiotic features difficult io be quantified (35,36,37,38,39). Furthermore all of this seem~ not to be sufficient if we do not relate their presence in situ with the keratinic substrata in the 80 soils provided by the fauna, including roan, thus the keratine becomes a potential reservoir for their saprotroph or potentially biotroph communities.
Considering the above, our frrst part in this research intends to analyze: 1) The distribution of these fungi in a latitudinal gradient of the Chilean big and small no rth (2000 km approximately), with the purpose of providing more ecological infor-mati<?n to the _little one altt<ady gathered in the ment10ned terntory (25, 4U, 9r). Z) IñeJT presence in extreme environments which represents about 2/3 of analyzed territory MATERIALS AND METHODS a) Geogrctphicallocation of the sampling areas 332 soil samples taken from coast and inland zones belonging to the first 5 regions of the Chilean territory (North and a part of central Z one) werc analyzed. Regional boundaries were not considered and this part of the co untry was subdivided into 4 groups of latitudes, ea eh with a 4!1 S-difference ( 450 kms. approximately). The former, starting fro m the northern frontier with Perú, include the following latitudes: 18º-22º S, 22 2 -26º S, 26º·3()2 S, 3QQ-342 S. In figure l , the 4 latitudinal zones with the sampling places selectcd in different transects between the coast and inland, are given in detail. A coast zone is considered to be that one encompassing from the sea as far as 10 km-maximum towards inland, while the inward zone is the one which is more than 10 km away from the coast and which reaches as far as pre-mountain chain zones. Coast and inland habitats in turn were divided into two new habitats: l. The urban-peripheric one, meaning peripheric boundary as the area stretching from the perimeter of tne city or village as far a1. sorne 3 to 5 kms. of <Ustance. 2 The wild one that includes the environment far from the urban centers, ar a distcmce greater than 5 km of the city periphery and with low human activity signs.

b) Sampling
Samples were taken among years 1985-1989 always in tbe same season of the year, from May to June (Autumn), and it consisted in the removal of 50 to 100 g. of surface of the soil (1 to 5 cm deep) by means of a sterilized trowel. Each representative sampling unit either of the urban-peripheric or wild habitat, consisted in a pool of 5 sub-units taken at r random from an approximate 50 m2 area. In each geographical sampling spot, a mínimum average of 5 samples in wild areas and one generally greater than 10 in an urban-peripheric area wen: got thc soil samplcs obtained werc deposited in ste rik plastic bag and sealed to prevent the lost of humidity. All the samples were frecz ed ( -201l C) for 1 week lo inhibit the mitcs. · e) Seeds and Cultures Aftcr freczing soil samples were processed according to the modified Orr's technique (26). Soits were arranged cvenly on 12 cm diameter sterile plates untíl covering half their height, sterile prepubescent human hair being added on the surface. The soil with its keratinic bait on the  surface was moistened with sterile distilled water added with chloramphenicol (0,10 g/1) and cyclohexamide (0,4 g/1). Plates were incubated at room temperature of the laboratory (16 to 200 C) for a 4month maximum period. In order to avoid dehydratation, they were occasionally added sterile distilled water. The observation of the fungal growth began as for the fifteenth day and later on at 15-20 day intervals. The control of the fungal growth on the keratinic bait was carried o ut with a stereomicroscope and isolates took place either by a direct observation or cultures with a ftne needle.
The frequency of occurrence of colonies of sorne Onygenal species or related fungus was counted only once for each petri dislv ..,, overlooking the number of times it could get repeated onit.
Relevant fungal species werc isolated directly from the platcs under the sleromicroscope by using 3 kinds o f agar: Corn Mea! (CMA), P otato carrot with yeast cxtract (1/1000) (PCA) and Patato dextrose (PDA). Cultures werc incubated at 25-27º C. The identification of isolates was based on mo nographícs and kcys mentioned m the references.

d) Statistical processing
To estímate the stability of the mycocenosis in a place, the Shannon-Weaver d iversity fo r species isolated in that "place" (habitat or latitude) was calculated. To stablish which latitudes and habitats were forming a similar conglomerate acording to the presence of species, cluster analysis, completelinkage, dustering computed on the basics of the Pearson's correlation matriz was used, and principal component analysis was performed on the covariance matri1e sample .
A BIOGEOGRAPHICAL OUTLINE OF THE STUDIED AREA.." Due to ecological conditions, mainly influenced by t he climate, the orography and the anthropic action, the distributio n and composition of the biomassof Chile is not simple. The marked latitudinallargeness and the o rography are used as useful elements to distinguish certain types of ecosystems (56,57,58), which in our collection areas we call Xeromorphic, Mesomorphic and Andino, according to Pisano's classification (55), which have different characteristics of flora and fauna.
Xeromorpbic ecosystem lt includes the first three regions of the country (Tarapacá, Antofagasta and Calama) among 18-300 south latitudes approximately and the characteristics of which are very similar in soil, climate and relief. It is char acterized by a scarce vegetal coberture that is ncver continuous and by t he sing ular adaptation of the species to the unsatisfactory conditions of humidity. It has huge areas fo r mining cxploitatio n yet their population density is very low (about 3 inhabitants/ km2 gathered mostly in urban zones).

Clima te
In the narrow coast strip (5 to 10 Km), a littoral desert~like climate with mínimum precipitations that increase slightly towards the south (0,7 mm in Arica; 7,7 mm in Antofagasta) can be seen. Low and homogeneous (15~1811 C) mean temperatures, constant fog.
In lhe inland zone, among 18-29Q south latitudes, approximately, there is a normal desertlike climate with clear skies, a greal atmospheric dryness and severe temperature fluctuations ( sometimes greater than 40Q e between da y and night). Absolute absence of precipitations all the year through.

Flora
The littoral desert-like zone exhibits a scarce vegetation mostly cacti and coast desert-type bushes. Herbaceous species are scarce.
In the inland zone (without considering the preandina or andina zone), flora is purely desertlike, with no vegetation or very little. Presence of Bromeliaceae (Tillansia lanbeki), Adesmis sp. and Atripex sp. Absence of woody zones, except for the existence of only one type of tree, the tamarugo (Prosopis tamarugo ), scattered in sorne areas. In sorne small "ayllus" (oasis) and valleys, tbere is a reduced agriculture, with the presence of herbs, bushes and sorne trees.

Fauna
In the coast zone, the presence of marines birds is remarkable, scarce turtles, rodents, depredators and cattle: limited mesofauna.
In the inland zone, in stony environments, sorne lizards and birds (mainly Tordus chiguanco). In the oasis zones there is a wide variety of birds, rodents, insects and mesofauna.
In general, live beings of the desert-like ecoregions keep a constant fight against their hostile environment, where plants and animals survive only in small communities.

Mesomorphic·temperate ecosystem
It can be subdivided into 2 classes: 1)The one located among 30-32 11 south latitude induding the 4th Region of the country, Coquimbo (Regional Capital, La Serena). lt is considered as a transitional zone, xeromorphic of the Chilean North and the higromorphic of Southern Chile. It has a complicated orograpby due to the transverse mountain chains which determine the existence of closed deep valleys. It is a purely semi~dry zone, with a > 50 inh/km2 population density in the urban-rural zone.
Soil. Their surfaces correspond to sorne 4.000.000 hectares approximately, 60% of which are adapted to the wild life. They are soils influenced by the climatic dryness, aridisol and afisol type, ( without considering the andino ones), light colored, rich in salts and carbonates, generally free of clays, Shortness of organic matter in zones far from hydric zones.
Climate. In coast zone, stepperic climate with plentiful clouds, precipitation increase (133 mm yearly in La Serena city). Low and homogeneous mean temperatures (14,7 2 C).
In the inland zone, the same climate yet with a great atmospheric dryness, moderare precipitations (100-150 mm yearly). Transverse mountain chains produce wide zones of air dryness with high mean temperatures in summer (28 11 C). The dryness period lasts about 8 months, having rains only in winter.
Coast and inland zones show sorne deep erosion causcd bv the destruction of the forest and the overpasturi~g of goats, one of the most important agents in the environment degradation, with a tendency to the coming back of desert-like habitats. The dryness period lasts about 8 months, with rainy periods mainly in winter.
Flora. In coast zone, clear sub-desert like bush and spiny bush (Cacti). Scarce woody communities and sorne areas for agriculture-cattle breeding exploitation, favored by the existing rivers.
The inland zone is rnainly shrubby, prevailing an extremely xeromorphic (Cacti) clear and low bush, with plants adapted to the dry and sunny environment (Puya cbilensis). There is plenty thorn (Acacia caven), sorne gramineous plants and forage herbs, especially Atripex species, which play an important role for the cattle.
Agricultura! exploitation areas related with the basins of the rivers.
Fauna. Mainly poor, in the coast there is predorninance of marine birds while land birds are observed in connection with valleys provided with irrigation. Few mamrnals, sorne rodents and their natural depredators, cattle is chiefly made up of goats.
2) The one lying among 32 to 34 11 south latitude which corresponds to the 5th region of the country (regional capital, Valparaíso). Beginning of the mesomorphic ecosystem, where a progressive aridity decrease and a precipitation increase are observed. The height of the coast mountain chain protects inland zones from the marine action. These latitudes are the most anthropized of the country, with a regional population density greater than 250 inhabitants/km2, distributed mainly in urban areas.

Soils
Their surface corresponds to 1.640.000 hectares, 50% of which are fit for forestal activity, a 30% for wild life and the rest for cultivation. Alfisol-type or prairie-type soils in coast zones. In inland zones they are of the entisoil type, belonging to the drab not calcareous group (in zones of moderate precipitations) and lo the alluvial and hurnic group (in humid zones).

Clima te
Chiefly ternperate, of the Mediterranean type either in the coast as well as inland. However, in the coast mean temperatures are more moderate because of the óceanic influence (14,8Q e in Valparaíso), with constant morning foggy days and a mean 360 mm rainfall very variable according lo the years ( reference Val paraíso city).
In the inland zone there are continental tendency areas with severe thermic fluctuations and dry air, having mean temperatures greater than 27º C in summer, due to the action of the coast moun-84 tain chain. There is a good agricultura! activity in irrigated soils because they are rich in organic matter.

Flora
In the coast zone, abundant herbs and gramineous plants, with a coast mesomorphic shrubby steppe, cultivation areas, forestal plantations (Pinus spp. Eucaliptos spp., Populus spp, etc.) and a sclerophilic native forest (very degraded) are observed. In more humid zones, the Chilean palm (Jubea cbilensis). In the inland zone, abundant herbs and gramineous plants are seen, a clear schlerophilic bush, a schlerophilic forest and steppe-like communities of thorn (Acacia caven). Areas with good agricultura! exploitation. The native vegetation loses importance before the introduction of foreign species.

Fauna
These latitudes exhibit the greatest variety of fauna in the country either of marine birds as well as Jand ones and small-size mammals. Different kinds of cattle and abundant mesofauna.

RESULTS AND DISCUSSION
In the present paper that includes around 1/3 of the national territory, of the 332 petri dishes under examination, 904 keratinophilic-lytic fungal isolates which belong to 45 species (17 genera) were isolated, and are described in detail in Table l.
In 74 (22.8%) of the soil samples collected from all latitudes examined, there was absence of growth of Gymnoascales and related fungi. The highest negativity was observed in wild places either coastal (33,33%) as well as inland (30, 76%) Table 3.
The greatest number of fungi isolates per plate in every latitude was detected in the U rbanper. habitat, mainly inland and within 26 to 34 11 S latitude. (Tables 2 and 3).
Peculiar geographical conditions of continental Chile makes it possible advantages in the utilization of sorne parameters such as: latitude, habital and population density (men and animals in relation to Urban-peripheric and Wild Zones). (AMA e).
86 The relationship between the human-animal presence in the environment and the distribution of keratinophilic fungi in soils has been demonstrated by many papers (11, 23, 25, 26, 27, 28, 29, 30, 36, 39 52) in different latitudes (mostly in the norther~ hemisphere), generally in direct relation to the quantity and quality of the prevailing organic matter (46), mainly supplied by the vegetable cover, the humus content, the presence of fatty acids ( 45) as well as the keratinic material ( 43) or other cm;npon~nt?. ~owever ~ue to the wide geographical dtstnbutlon of tbetr numerous taxa and tbeir ability to metabolize as saprotrophic a great variety of substrata existing in the soils, they are able to coloni~e feather, fur, nail, hoof, horn, bone, dung, dropptng, paper, decaying vegetable matter and other substrata (47). This variability in the pro· duction of enzymes induces to think of the fact that these fungi like other fungal groups are able to make use of different metabolic strategies unde r the nutritional stress and tbe habitat conditions ( 48) rendering difficult their position in strict degrading categories which are still under examination at present (52,54,17).
The_ varied keratinolytic, keratinophilic, cellulolytJc or other properties common to the taxon ( Onygenales) are not reasons enough to consider the ir particular e nzymatic potentialities as an usual standard of the species in the habitat, but rather as a selective strategy of the dominan! ecological situation for a particular substratum. This seems lo be true in sorne of our isolates where the habitat and possibles varied substrata lodge the same species in the latitudinal gradient (Tables 2  and 3).

a) lsolated genera
The most dominant and represcntative genera according to their habitar in every latitude were in decreasing arder: Chrysosporium Corda, Aphanoascus Zukal, Malbranchea Saccardo, Trichophyton Malmste n and Gyrnnoascus Baran. (Figures 2 and  3). Chrysosporiuni was the most abundant ( density) genus in every latitude and habitat, reaching together with its teleomorph Aphanoascus, about 33-40% of the total isolates. Next in relevance is Mal~ranchea with a,9, 4% (Figures 2 and 3). In spi· · te of thc extended literature about the presence of the genus Chrysosporium and Aphanoascus there is not a uniformity of criteria that makes it p~ssible lo relate their presence in different habitats and soils with regard to the biogeography and climate. Our greatest isolates in the coast (Urban-pcr.) ( Figure 3) would confirm the abundancc; of certain 88 species in a linoral mediterranean climate (36,49), a situation that can be easilv seen to sorne extent in Aphanoascus verrucosus, · Chrysosporium tropi· cum and Chr. pannicola. While species of the genus Malbranchea, seem to prefer the hottest and driest climates of the inland (Urban-per.) ( Figure  3) lt is evident that Apbanoascus or its anamorph (Chrysosporium) are able to adapt themselves to different edaphic, climatic and nutritional situations keeping a constancy or dominance · all over the latitudinal gradient, this is why they must be considered among the Onygenales with the highest competitive capacity.

b) lsolated species b-1) Dominance and constancy in babitats and latitudes
The highest number of species was found in the genus Chrysosporium with 9, Gymnascella with 6, Malbranchea with 5 and Aphanoascus with 4 (Table 1, 2, 3).
Of the total of species isolated, we considered 8 teleomorphs together with their corresponding anamorphs (holomorphs) by this reason we will analyze results by basing in a pool of 37 taxa (Table  2 and 3). The most important holomorphs were: Aphanoascus fulvescens and its anamorph Chrysosporium sp., A. keratinophilus · Chrysosporium keratinophilus, A. verrucosum • Chr. tropicum, Arthroderma quadrifidum • Tricbopbyton terres· tre complex and Gymnoascus reesi; al! of them appcar as euridominanl according to the latitudinal gradient of the habitar (with over 5% of isolates in the 75% or more of the parameters considered) and as constant (with presence in every parameter) .
A second group of important species is made up of stenodominant (appearing in over 5% of the isolates in 25 or 50% of the parameters, being also constant in almost every latitude and habitat (Tables 2-3). Considering both groups latitudinally, we can see that 28,6o/c tends to bring out in the tropical latitudes (18 to 262 S), such as A. verru· cosus -C. tropicum, Gymnascella dankallensis, Uncinocarpus reesii • Malbranchea anarnorphs and Gymnascella aurantiaca. While in southernmost latitudes (26 to 34Q S), a 35,7% is represented by: A. keratinophilus -C. keratinophilus, Arth.    Table 2).
Taking into account the habitats, 64,3% is more remarkable in a coastal environm.ent rather than inland, showing similar preferences for a wild environment rather than for an Urban-per. one. they are: A. verrucosum and its anamorph, A. fulvescens and its anamorpb, Arth. quadrifidum and its anamorph, Gymnascella dankaliensis, C. pannicola, Geomyces pannorum var. pannorum, Auxartbron umbrinum, Arth. uncinatum and its anamorph and Amauroascus aureus (Table 3).
In every latitude, the holomorphs of: A. fulvescens, A. verTUcosus and A. keratinophllum revealed the highest frequency and occurrence, only excelled by Gymnascella dankaliensis in 18-222 S latitude and Tricbopbyton terrestre complex in 30-3411 S latitude (Table 2).
In the 4 habitats, the 3 holomorphs of Aphanoascus appeared again, however A. verru· cosus is not dominant in the wild inland ( Table  3).
The frrst 21 taxa of the Table 3 (56,8%) were classified as constant because they appeared in 3 or more of the 4 latitudinal zones sampled or in 3 or more of the 4 habitats. Notwith standing Chrysosporium merdarium, MaJbrancbea deodritka, Microsporum cookei, Amauroascus echinulatus, Oncocladium flavum and Gymnascella aurantiaca were never dominant (only constant) . These taxa could be considered as replacement species (by the dominance) when mycocenosis changes its presence due to abiotic factors as well as to interspecific competence among Onygenales and the abundant primary colonizers of the keratine not belonging to this taxon.
In spite of the fact that a good deal of the examined soils are extremely poor in organic matter, especially within, 18-30 2 S latitudes (55,56,57,58), even 30% of them come from extreme (desert) environments for the fungal growth or the development of other microorganisms (See Biogeographical outline ), the number of On~enal~s species and related laxa that was obtamed 1s considerable.
Since the abundance of species was higher in Urban-peripheric zones it is possible to consider these habitats as beterogeneous, disturbe'd, and with an extensive differentiation of microhabitat (10,59,60). Domestic animals directly or indirectly related to the economy of the man, by promoting the dispersion of minor species, because. of l.he continuous expansion and division of their iíi:éhes (10) malee up at the same time a potential reservoir of saprotrophic or potentially biotrophic species whicb fall upon in the epidemiology of sorne mycoses (61,62). The habitat considered as wild bears to tbe contrary more homogeneity due to the structure of the soils and the little human activity within 18-260 S latitudes, whicb reverts slowly towards major latitudes. Yet in spite of tbe climatic rigours of the fust latitudes and the incre(!.se of tbe population density in the second ones, it can be considered as undisturbed (4). lts minor fungal community of Onygenales can be somewhat related to not only the prevailing abiotic factors ~ut also to a majar interspec·. ific competence resultmg from the lower amount of microhabitats ( 63, 64, 65).

b-2) Reproductive strategies
In the analysis of the reproductive (teleomorphs) or multiplicative strategies (anamorphs) observed on the petri dishes in the 8 taxa that were submitted as holomorphic (Apbanoas<:us fulves· ceos, A. verrucosus, A. keratinophilum, Arth. uncinatum, Artb. quadrifidum, Arth. gypseum, Ctenomyces serratus, Uncinocarpus reesii), the multiplicative strategy exceeds (68% ) the reproductive one in the latter. When the sampling uníverse got subdivided into only 2 groups for a wide latitudinal gradient (18 to 26 11 S and 26-34 2 S), the first one exhibited a higher rate of multiplication than the second one (with a increase in the reproductive strategy), the coastal and inland habitat (Urban-per.) being, in general terms, the most representative of these 2 strategies (Table 3). A. fulvescens, as the only exception, showed mostly its cleistothecia in evcry latitude ( 68% ), exhibiting its anamorph under a reduced conidiogenesis, sometímes almost absent (a situation not similar in cultures). Conversely, Uncinocarpus reesii was most recorded in 18-2211 S latitudes and its anamorph in those located southernmost (  ( 42) can be related to: the desert characteristics of the most tropical latitudes, a decrease of niches (little vegetable cover) or to the temperature that can allow genetic adaptations for extended periods of time both in the species and in the conspecific populations by a natural selection (50). Based on the above, A. fulvescens especially, Chrysosporium keratinophilum and C. tropicum, can be considered as euritherms.

b-3) Latitudinal distribution patterns and biogeography
In the quantitative analysis of the Onygenales and related hyphomycetes community isolated in all the habitats (  Table 2); however Arth. gypseum, Arth. uncinatum, G. pannorum var. pannorum and Chr. pannicola became affected to sorne extent by the latitude. AH of these species have a wide distributian in many places of the world (17, 23,25,31,33,43,49,68) and can be classified as "damesticated" because of their clase relationship with urban-peripheric habitats and the man's activities. The preference far ane ar several kinds of habitats can reflect degrees of metabolic adaptation to the diversification of the existing substrata and where the keratine can be one of the main energetic sources and the reservoir for these fungi (31).
Basing ourselves in this majar ar minar nutritional selectivity, it can be seen that the 12 species considered as damesticated, G. pannorum var. pannorum and Gym. reesii prefer mostly the wild habitat, while Ct. serratus and Arth. gypseum prefer the urban-peripheric ane (Table 3), as to the remaining 8 taxa show signs of preference for these twa habitats which are hard to evaluate, or else they get distributed in similar percentages in both of them (Table 3). We can classify the latter as enzymatically self-sufficient and competitively very active taxa ( considering their dominance) in environments disturbed by man and animals.
G. pannorum var. pannorum and Gym. reessii are not considered as keratinolytic (67,68), 92 however the former has been isolated from different types of soil and vegetable detritus as well as from man's skin (67) and animals (41).
As to the second one, it is considered as coprophilous in the excrement of different wild animals (17) and common in desert soils and poor in organic matter (68). lts presence in keratinic baits proves its adaptation to this substratum.
Quantitative and qualitative variations found in the mycocenosis can be analyzed related _t~ the ecosystem yet as the structure of the fungal community has nat been sequentially considered in the time, it is nat passible to assert the value of the distribution patterns in an age other than the studied one. W e will only affrrm that the diversity of species in the latitudinal gradient is best appraised in the mesomorphic ecosystem and it can be related to 1) A better climatic stability inducing to a fme specialization and adaptation of communities higher than in areas exhibiting erratic climatic regimes (70). 2) A better stability in organic matter (greater vegetable cover) which pramates an increase in the differentiation of niches (93,94,95).
3) And the increase in the population density, the highest in the country within 32-34 2 S latitudes.

b-4) Associations among Onygenales.
The distribution on plates of the most frequenlly associated Onygenales allowed to note two distinct situations between habitat and latitude, where the wild environment in every latitude showed the lowest number and frequency of this associations, withom a clear pattern of common species competing for the substratum; while in the urbanperipheric habitat within 18-26 2 S latitudes, 60% of the plates examined generally 4 taxa got associated to sorne extent such as: U. reesii, Ct. serratus, A. fulvescens and A. keratinophilus and its related anamorphs. In the same habitat in 26-34 2 S latitudes, the highest number af assaciations was obtained, being Arth. quadrifidum, Ct. serratus and A. keratinophilus and their anamorphs together with Chr. pannicola the most remarkable.
lt is difficult to find an explanation for the associations among Onygenales in relation to its biotope (31) even more when seasonal variations can affect the course of the succession, distribution and survival of populat~ons.
Our analysis did not take into account the great number of primary colonizers of the keratine that we have isolated (68 taxa) yet not included in this paper. Many of them have a marked keratinolytic activity, especially Paecilomyces lilacinus, the most frequently recorded in every habitat and latitude. Situations mentioned above added to the interspecific competence do not allow us to make a further discussion.

e) Ecological parameters
Considering Pearson's affinities among latitudes, (Table 4), 2 groups can be easily distinguished: the first one includes 18 to 26 2 S latitudes where r = 0,74 is very significant (p < 0,001) and the second one from 26 to 342 S latitudes, where r = 0,77 is also very significant (p < 0,001). This observation is complemented by the fact that similitudes between these 2 groups of latitudes preve to be quite minor and little or not significant at all. This is also confirmed by the clustering among latitudes shown in Figure 5, where it is also observed that the mentioned differentiation takes place inland yet not in the coasl. By observing dominances and constancies of species (Table 2), we can see that differences between both groups of latitudes become enlarged by: 1) Arth. uncinatum and its anamorph, Arth. quadritidum and its anamorph, Chr. pannicola and Ct. serratus and its anamorph within 26 to 34º S latitudes and by: 2) ,Apb. verrucosus and its anamorpb, U. reesii and its anamorph, Gymnascella aurantiaca, G. dankaliensis, Cbry. merdarium and G. pannorum var. pannorum, within 18 and 26 2 S latitudes. The greater abundance of species isolated within 26 to 34° S latitudes which did not appear northernmost also contributes to these differences.
Out of the pool of 37 taxa isolated, only 35% appear in the soils of south latitude (26 to 342 S), among more tropical latitudes (18 to 26° S), to tbe contrary, only 2 (5,4%) do not appear southernmost (Arachnomyces sulpbureus and Myxotricbum deflexum, Table 2, below) . This greater abundance within 26 and 342 S latitudes does not correspond with the greatest diversities which are observed in intermediare latitudes, especially between 22 and 26° S latitudes, where the observed diversity reaches a 93,8% the maximum one (Table 5).
The smaller diversities in the extreme latitudes are mainly due to the strong dominance of Arth. quadritidum and its anamorph in tbe southernmost one and Gymnascella dankaliensis, A. verrucosum and U. reesii in the most tropical latitudes.
The reason for this minor diversity of fungal species is not clear, it can be related to the inability of these soil fungi to adapt themselves to high and low temperatures (46). This would make it possible to assume that the more stable mycocenosis in the sampling period was the one observed within 22 and 2611 S latitudes. Considering affinities between habitats we can observe that the similitude is significant (p < 0,001) among Urban-per. ones and similar to that which is observed among wild habitats (Table 6). Conversely, the affinity between Urban-per. and wild is low in the coast yet surprisingly tbe highest, is found inland. This is also strenghtened by the clustering among habitats shown in Fíg. 6 ( Table 6).
These observations would denote that: 1) In longitudinal direction (habitat), differences bétween similitudes would be fewer than in latitudinal direction and 2) Among widely anthrophized (Urban-per.) and wild soils there would be a high inland similitude yet a low one in the coast. Table 6 PEARSON'S AFFINITIES AMONG HABITATS In dominances according to habitat (Table 3), we can see that 9 taxa produce the greatest differences between Urban-per and wild habitats in the coast either because they are absent in some of the 2 habitats or else because they domínate only in one ofthem.
On the contrary only 5 inland taxa produce this type of differences.
The presence of rare species ( distribution of rarity) can be observed in the bottom of Table 3, where the Urban-per. ioland habitat is the most represented followed by the Urban-per. of the coast.
The 2 Urban-per. habitats exhibited the lowest diversities in relation to their maximum diversities ( Table 7) in correspondence with the remarkable dominances of the holomorphs: A. fulvescens, Arth. quadriftdum and Ct. serratus, the 2 first ones in the coast and the latter inland This makes it possible to think that the mycocenosis of wi1d habitats in the period studied are the most stable ones.
In simultaneous diversities in each habitat and latitudinal zones, wild habitats always show tbe highest relative diversities (90% or over) without relevant differences in the latitudinal gradient.
However inland, relative diversities tend to bécome equal between Urban-per. and Wild habitats ( Table 8)    lt is not possible to discuss the results of thís investigation witbout a partial consideration of the wide literature available in the taxonomic suprageneric and generic ranges of tbe Ascomycota classified either as Eurotiales, Onygenales or Gymnoascales. The acceptance or not of the nomenclature in force is not the goal of our researcb work and the sympathy for sorne scbeme reflects rather a practical and objective situation. References included represent only a part in the present state of this fungal systematics. The identification of them is extremely difficult because names have been used inconsistently, and one reason for confusion among them is that the species have been wrongly named or no longer considered valid by one or other specialist.
In tbe biology of Onygenales, the enthusíasm of the taxonomists seems to have not stopped, creating nomenclature problems arnog the mycologists ( Ex. 12, 13, 14, 15, 16, 17, 19,). This positíon produces an alteration in the necessary taxonomic stability which only has to be accepted when changes arise from a more thorough understanding of evolutionary relationship (71,73).

d-1 Onygenales-Eurotiales Relationships
The Ascomycetes considered as Onygenales have tbeir origins since the typification of Onygena (Onygenaceae) done by Fries 1884. Ranges of Family and Order have been widely and disagreeingly used without satisfying most of the taxonomists. The new concepts of arder and its 4 families proposed by Currah (17) seems to have the highest consensus at present, although previously Malloch (21,22,72) (75) only one).
The main taxonomic parameters of thiS arrangement are: the shape, size and symmetry of the ascospores, the structure of the asci and the morphology of the ascomata initials, considering that phylogenetically there must not be a separation between the Eurotiales and Onygenales because of its relationship to Endomycetales and Erysiphales .. This is an advanded scheme which we must appraise cautiously especially in the Onygenaceae wherein genera are still considered under the terms of "blastic and thallic".
Erikson & Hawswortb (77), in their outline of arder and families and genera of the ascomycetes, do not agree with this scheme. In spite of the fact that the arrangement of the generic characteristics seems to be significant in the Eurotiales, this situation does not seem to become reflected yet at the suprageneric levels.

d-2) Aphanoascus Zukal
The synonymia of Aphanoascus Zukal with Anixiopsis Hansen, imposed by Apinis (78)  ( with the recent species A. australis, and A. punsolae (84). As descriptions of the ascospores were carried out under a Scanning electron micrascope (SEM), the observation of sorne features of the epispore under the optical microscope are not easy to view, as well as the close margins of their measurements among sorne especies ( width and length) especially when small morphological differences observed in sorne of its anamorpbs in Cbrysosporium and Malbranchea are evident.
Cano (49) includes Chrysosporium tropicum as anamorph of Aphanoascus verrucosus Cano and Punsola. Later on, Cano and Guarro (69) mention Chrysosporium sp. as the anamorph of this species, arguing that its conidia are similar to C. tropicum. With this, tbe position of C. tropicum seems doubtful and looks like what happened with sorne strains equal to C. keratinopbilum, that are members of an anamorph pool being morphological very similar ( complex?). · Aphanoascus, Chrysosporium and Malbrancbea, seem to bave a considerable amount of genetic variations, this could differ in the way that this is distributed among the existing population, making the taxonomic arrangement at species level difficult.
Consequently, if the teleomorpb-anamorph relationship ( with sorne exceptions) lacks a taxonomic usefulness, which turns out to be undesirable, thus Chrysosporium looks morphologically more complex and heterogenous, a point of view which is agreed by many advanced mycologists. It is necessary a better delimitation witb genetic studies which may bring many surprises that we are not able to appraise yet in the whole.
After the revision of Aphanoascus by Cano & Guarro (69) we have restudied the majority of the isolated strains, their d~scriptions -and slides of A. fulvescells and C. keratinopbilum kept during this work. Many of these strains were reclassified as A. fulvescens and A. keratinophilus. We have the impression that our percentages of A. fulvescens may be slightly higher than the ones here included, confirming its euridominant category.

d-3) Gymnascella Peck. and Gymnoascus Baranetzky
The genus Gymnascella Peck., was described for the single species Gymnascella aurantiaca Peck 1885, placed in the N.Y. State Museum with an inadequate description for recognizing the fungus.
Saccardo (85) reclassifies it into Gymnoascus, what was confirmed later on by von Arx (13), who considers it as Gymnoascus reessll. Orr et al. (19) reintroduced the genus Gymnascella with the type species Aracbniotus verruculosus Orr and Kuehn ( = A. aurantiacus) be cause of its priority over the genus Aracbniotus Schroeter. Currah (17) reexamines an isotype of Gymnascella aurantiaca located at TRTC and fmds that it represents the same taxon as Arachniotus aurantiacus Kamysc, therefore he confirms tbe priority of Gymnascella over Arachniotus. He places all oblate ascospore species in the frrst and those with double equatorial band in the second.
Gymnascella is a polyphiletic and beterogeneous genus which comprises at present most of the species previously included in Arachniotus The inclusion of Narasimhella is not agreed by von Arx & Samson (86) because this taxon is not closely related due to its bivalvate ascospore, even though these authors accept that the 12 species described by Currah (17) in Gymnascella are valid and well delimited. The constant efforts to avoid proliferation of genera in the Gym.noascaceae and Onygenaceae made by von Arx (12 -13 -14) continue with the enlargement of the generic concept of Gymnoascus done by this investigator (15) who encompasses within the latter every Gymnoascaceae with lenticular or discoidal (not bivalvate), circinate, arqued or comb-like appendix ascospares. Therefore he considers Gymnascella and all the genera befare mentioned to be synonyms of Gymnoascus.
lf the possible simplification of the ascospores forms from the complex ones like the Gym.noascus ruber ( = Arachniotus ruber), with equatorial groove bordered by distinct ridges and pote thickened, to Gymnoascus desertorum ( = Gymnascella connueos = Arachniotus desertorum) with a broad shallow equatorial depression, to Gymnoascus reessii, with smootb and oblate ascospore, can represent an evolutionary route, it is not less valid that many mycologists may think that the identity crisis has not finished in the Gymnoascaceae and Onygenaaae. Nevertheless the idea must not be discarded as ao alternative of classification also applied without much success in the past by Apinis (11), where he includes within Gymooascus the genera Pseudogymnoascus and Auxarthroo.
Tbe taxonomic determination of Gymnascella littoralis (?) ( = Plunkettomyces littoralis) in keratinic substrata, was based on the ascoma, peridial hyphae, and ascospore. The latter are smaller than those described in literature (Phot. 24,25). The inland (Urban per.) non marine habitat make us doubt if this species is really a smaller variant or belong to another neighborn specie. Nevertheless the ascospore never show ed polar thickenning and were always smooth.
In our investigation the ddimitation of genus Gymnoascus is based in Orr (19) aod Currah (17) criteria.
Gymnoascus reessii was the most common species of tbe genus and the morphological variations of its appendages in the reticuloperidium were better appreciated directly in petri dishes over the keratinic bait (Phot. 1 -2 -3).

CONCLUSION
According to the set of ecological and biogeographical conditions analyzed, we can conclude that: 1) The diversity, density anlfd richness of species was: a) Higher among 26 to 34 11 S latitudes, with a superposition of characteristics from xero and mesomorph~ ecosystems which among 18 to 2611S latitudes sbow distinct desert-like features.
b) Higher in most anthropophized (urbanperipberal) and inland habitats, with a greater diversity of niches and organic supply than wild atid coasta) hábitats. e) Higher in the species of the ' genera Aphanoascus and Chrysosporium, probably due to tbeir greater adaptive and competitive capacity in the latitudinal gradient.
2) The richness of species was observed mainly in relation to th:e rarest .taxa which may seemingly exhibit nutritional, edaphic. or climatic limitations in a particular habitat.
3) A similar pattern of latitudinal distribution for 12 cosmopolitan taxa in the seasonal period studied could be seen, what made to consider them as euridominant or as stenodominant because of the efficient production, dispersion and survival of their propagules in the different habitats. Species with a higb population density in the different geohabitats of tbe latitudinal gradient kept a close equilibrium among themselves and the remaining inycota of the community. The composition of the various macro and microhabitats can be conclusive in the structure of the community present in them, giving rise to a model of population organization able lo exploit the diversity of ex:isting substrata with similar efficiency.