Informally referred to acellular or plasmodial or

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informally referred to acellular or plasmodial or true slime molds, The Myxomycetes CLASS has over 900 documented species distributed into over 62 genera, Myxomycetes inhabits a wide range of decaying woods debris, twigs, leaf litters, dungs, moist soil, bark of living trees and all other forms of organic matter They are characterized by a naked, saprophytic somatic/trophic/assimilative/feeding phase of plasmodium which is a protoplasmic mass, holocarpic, active, free-living structure, and amoeboflagellate (swarming amoebae), The plasmodium may also form other fruit bodies like
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Continuation The plasmodium is product of syngamy, secretes slime, valuable to the taxonomy of myxomycetes and are of 3 different types that include protoplasmodium, Aphanoplasmodium and Phaneroplasmodium, At maturity, the plasmodium systematically organized to form a sporophore (peridium enveloped sporangium), stalk and basal disc (hypothallus) while it converts into an irregular hard sclerotium or macrocyst when stressed/strained by starvation, harmful chemical signals and drought Sexual reproduction is isogamous and involved haploid non-slime secreting swarm cells or myxoamoebae. They also reproduce asexually. While there are different classification model in mycological and protistological literatures, we follow this adapted model of classification that limits myxomycetes into 5 ORDERS (see table 4) and Ceratiomyxales based on fruit body morphology Ceratiomyxales (coral slime molds) appears in nature as white frost-like growth on moist woods or wood debris, only has 1 genus (Ceratiomyxa), produces sporophore that lack peridium exposing the spores (exospores) on Columna or carried on a slender stalk as a reduced-sporangium (monosporous).
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Table 4 : Adapted classification of myxomycetes and their basic difference in somatic and fruit body type Order of Myxomycetes Examples of Genera Nature of Plasmodium Type of Fruit Body Liceales Lycogala, Dictydium, Cribraria, Reticularia, Licea Protoplasmodium Aethelium, Capillitium, Sporangium Echinosteliales Echinostelium, Clastoderma, Barbeyella Trichiales Arcyria, Trichia, Hemitrachia, Metatrichia, Dianema, Perichaena Plasmodium with features of both Aphano- and Phaneroplasmodiu m Plasmodiocarp Stemonitales Comatrichia, Stemonitis, Macbrideola, Brefeldia, Lamproderma Aphanoplasmodium Capillitium, Sporangium Physarales Fuligo, Physaru, Willkommlangea, Leocarpus, Craterium Phaneroplasmodiu m Sporangium
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Life Cycle Pattern of the CLASS- Myxomycetes Unlike the Acrasiomycetes, the spores released from the sporangium germinates into either myxoamoebae or swarmers (amoeboflagellates – whiplike flagella) as dictated by microhabitat conditions. Either of the haploid germination products which are relatively ephemeral can: (i) undergo fusion to form a diploid zygote, (ii) switch from one form (myxoamoba) to another (amoeboflagellate) and vise-versa, (iii) progress to form microcyst when stressed, (iv) exist briefly as a trophic stage.
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  • Fall '19
  • Spore, Slime mold, multinucleate sporangia

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