Feeding habits of Collembola and their ecological niche

Abstract

THIS WORK WAS CONDUCTED TO DETECT CHANGES IN FEEDING HABITS OF SPRINGTAILS, RELATED TO THEIR ECOLOGICAL NICHE IN THE ECOSYSTEM. WE PRESENT THE RESULTS AND COMPARE OUR OBSERVATIONS ON THE DIET OF COLLEMBOLA, IN THREE DIFFERENT ECOSYSTEMS: 1) ONE TROPICAL RAIN FOREST IN VERACRUZ, 2) TWO CULTIVATED FIELDS IN HIDALGO, AND 3) THE EPIPHYTIC PLANT TILLANDSIA VIOLACEA FROM A TEMPERATE FOREST, ALSO IN HIDALGO. THERE IS A CLOSE ASSOCIATION OF SOME SPECIES WITH SEVERAL MUSHROOMS IN THE TROPICAL RAIN FOREST. SPECIMENS FROM CULTIVATED FIELDS HAVE VEGETABLE MATTER AND FUNGAL CONIDIA IN THEIR GUT CONTENTS. THERE IS A DISTINCT TYPE OF FEEDING IN THE SPECIES ASSOCIATED TO EPIPHYTIC PLANTS. IN THE LATTER, THE DEBRIS OF ALGAE, DIATOMS AND BACTERIA WERE FOUND. DURING THE DRY SEASON, THERE WERE FRAGMENTS OF PROSTIGMATA AND ASTIGMATA (ACARIDAE) MITES IN THE GUT OF PTENOTHRIX MARMORATA. IN SEIRA PURPUREA (BOTH IN THE RAIN AND DRY SEASONS), THERE WERE FRAGMENTS OF EXUVIA OF SPRINGTAILS, AND ALSO SOME PARASITIC NEMATODES. THE PRESENCE OF MITES IN THE DIGESTIVE TRACT OF COLLEMBOLA FROM THE EPIPHYTIC BROMELIADS COULD PROBABLY BY EXPLAINED BY THE FACT THAT DURING THE DRY SEASON, THE POPULATIONS OF ASTIGMATA AND PROSTIGMATA ARE ENORMOUS (MORE THAN 5000 IND.M-2) AND PROBABLY CONSTITUTE PREY FOR THE SPRINGTAILS. IT IS ALSO PROBABLE THAT THEIR DIET WHEN THE CONDITIONS OF ECOLOGICAL NICHE CHANGE