Krmpotic, C.M., Scarano, A.C., Andrés Laube, P.F., Ciancio, M.R., Loza, C.M., Acuña, F., Castro, N.N. and Barbeito, C.G. (2024). The double pores and skin of the pink fairy armadillo, the peculiar integumentary system of Chlamyphorus truncatus Cingulata (Mammalia, Xenarthra). Journal of Zoology, vol. 322, pp. 203-220. https://doi.org/10.1111/jzo.13136
The “pichiciego menor” or pink fairy armadillo (Chlamyphorus truncatus) is likely one of the world’s most peculiar mammals, drawing the eye of early naturalists who noticed it. This small armadillo spends nearly all of its time burrowed underground, resulting in restricted information about its biology. Its scientific identify refers to its distinctive armor; ‘Chlamyphorus‘ means “carries a blanket”, alluding to the pink-colored dorsal armor that covers its gentle, white fur like a cloak. This represents a duplication of the dorsal integument, a singular characteristic amongst mammals, and even amongst armadillos. Moreover, the advantageous fur beneath the dorsal armor is extra much like the fur of different subterranean mammals than the pores and skin fur of different armadillos.
Persevering with with the that means of the scientific identify of the fairy armadillo, ‘truncatus‘ refers back to the perpendicular place that the pelvic defend takes with respect to the armor, used for closing the exit of the burrows throughout excavation, stopping the entry by predators and rainwater. All these integumentary traits that may give this peculiar armadillo a starring position within the film ‘Unbelievable Beasts’ naturally piqued our curiosity and led to a collection of questions, reminiscent of: What kind of keratinization do its scales exhibit? What’s the configuration of its skinny osteoderms, and to which tissues are they related? What’s the nature of the pores and skin beneath the armor? Do they possess mechanoreceptors like vibrissae, even when indistinguishable from the remainder of the fur? In an try to handle these questions, we carried out an in-depth examine of the integumentary system of C. truncatus, together with the identification and outline of vibrissae via histomorphology and the usage of MicroCT on the osteoderms of each the dorsal armor and the pelvic defend. We then sought to grasp the connection between their morphology and predominantly subterranean habits and in contrast these with different fossorial armadillos.
All through our analysis, we confronted varied challenges, such because the complicated histological means of osteoderms, and particularly, the decalcification processes of osteoderms in several areas of the armor for subsequent histological processing. Publish-processing of MicroCT knowledge (segmentation and technology of 3D fashions) was difficult because of the intricate inner microstructure of the osteoderms. This course of consumed a major period of time however finally allowed us to understand the complicated relationship between the totally different buildings composing the armor.
Via these research, we discovered that the dorsal armor of C. truncatus considerably deviates from the everyday armadillo sample. That is primarily because of the general flexibility of virtually the whole armor, attributed to the thinning and bony conformation of its osteoderms, in addition to variations in keratinization of its scales. Moreover, the association and presence of hairs within the final cellular bands and the primary bands of the pelvic defend look like associated to biomechanical variations that present advantages when burrowing and shifting via tunnels in sandy soils.
Concerning the pores and skin with out osteoderms, it reveals convergent traits with different subterranean mammals (rodents and marsupials), such because the plentiful and extremely versatile hairs solely related to sebaceous glands. This attribute permits for higher motion via the tunnels the place this small armadillo navigates. Then again, the vibrissae preserve a morphological construction much like different armadillos however with thinning and shortening of their hairs. These options are possible linked to passive monitoring of tunnels, a typical statement in different subterranean mammals. The globally convergent mosaic evolution of subterranean mammals, pushed by comparable environmental constraints and pressures, serves as a wonderful instance of evolution via pure choice.
Cecilia Krmpotic