Scientists have described a new species of the Macrobiotus pseudohufelandi complex from sand dunes of inland Finland.
Macrobiotus naginae. Scale bar – 100 μm. Image credit: Daniel Stec.
“Animals that live in the soil have specific adaptations,” said Dr. Matteo Vecchi from the University of Jyvaskyla and colleagues.
“Animal species living underground in the soil show shortened, reduced, or absent limbs compared to closely related species living on the surface to allow a less restricted passage through cavities between soil particles.”
“This pattern of limb reduction has also been observed in tardigrades, where multiple lineages that have colonized the below-ground habitat show independent reduction and/or loss of legs and claws.”
“In the tardigrade superfamily Macrobiotoidea, leg and claw reductions are a common trait found in the Macrobiotus pseudohufelandi complex.”
The newly-discovered species lives in mosses and lichens growing on sandy soils in Rokua National Park in the North Ostrobothnia region of Finland.
Scientifically named Macrobiotus naginae, it has very reduced claws which are advantageous for crawling between sand grains.
“This contribution raises the number of formally described species attributed to the Macrobiotus pseudohufelandi complex to five,” the researchers said.
“The presentation of a dichotomous key to this complex will facilitate future studies on those taxa.”
“Furthermore, the presence of Macrobiotus naginae in association with inland sand dunes illustrates the importance of this ecosystem to peculiar meiofauna taxa that have clearly developed adaptations — such as reduced claws and legs — and highlights the importance of protecting these unique habitats.”
The authors also found the first direct evidence that moss-dwelling tardigrades are able to survive the passage through the gut of land snails.
“We were able to recover active tardigrades from the feces of 25% of wild caught Arianta arbustorum snails,” they said.
“One of the two species thus collected was able to persist in the laboratory.”
“It was found that 1/3 of all ingested tardigrades were defecated alive, with a peak at day 2 post ingestion. Furthermore, these recovered tardigrades reproduced in laboratory conditions.”
“This two-day delay could result in dispersal distances of about 10 m. This is a considerable distance for organism under 1 mm, for which just few millimeters of dry area would thwart its movement.”
“Moreover, snails and tardigrades share the same moss-rich and humid habitats; therefore, the destination of this snail-ride is likely suitable for the surviving tardigrades.”
The team’s paper is published in the journal Zoological Studies.
_____
M. Vecchi et al. 2022. Macrobiotus naginae sp. nov., a new xerophilous tardigrade species from Rokua sand dunes (Finland). Zool Stud 61: 22; doi: 10.6620/ZS.2022.61-22
Source link: https://www.sci.news/biology/macrobiotus-naginae-11380.html
