Abstract
In the context of the project “The Nature Protection Trust of Seychelles”, three species new to science are described: Calcarobiotus (Calcarobiotus) parvicalcar sp. n., Macrobiotus modestus sp. n., and Itaquascon pisoniae sp. n. Calcarobiotus (Calcarobiotus) parvicalcar sp. n. differs from the other species of the genus in having very small basal spurs of the claws; from some of them also in lacking eyes or in metric characters of placoids or claws. Macrobiotus modestus sp. n. has a very simple buccal armature (only three thin transverse ventral ridges are present and the three dorsal ridges are joined together forming a single transverse dorsal arc), and a long and narrow buccal tube with stylet supports inserted at 67–70 % of its length. It differs from the most similar species, Macrobiotus humilis and Macrobiotus madegassus, in some characteristics of bucco-pharyngeal apparatus and eggs. Itaquascon pisoniae sp. n. has the buccal tube slightly longer than the pharyngeal tube (pbf index = 54–55), pharyngeal apophyses and placoids are absent, a very faint cuticular bar near the internal claws of the first three pairs of claws, and no cuticular thickenings on the hind legs. It differs from the most similar species of the genus, Itaquascon placophorum, in having a smooth cuticle, shorter claws, in lacking placoid and the cuticular bar between the claws of the hind legs. Including this study, 30 species are recorded in the Seychelles, 15 of which are currently considered endemic for that archipelago.References
Abe, W. & Ito, M. (1994) Itaquascon globuliferum, a new species of Tardigrada (Eutardigrada: Hypsibiidae) from Japan. Proceedings of the Japanese Society of Systematic Zoology, 51, 8–11.
Abe, W. & Takeda, M. (2000) A new Calcarobiotus (Tardigrada: Macrobiotidae) from the imperial palace of Japan. Zoological Science, 17, 2, 259–263.
Barros, R. de (1939) Itaquascon umbellinae gen. nov. spec. nov. (Tardigrada, Macrobiotidae). Zoologischer Anzeiger, 128, 106–109.
Bertolani, R., Guidi, A. & Rebecchi, L. (1996) Tardigradi della Sardegna e di alcune piccole isole circum-sarde. Biogeographia, 18, 229–247.
Binda, M.G. & Pilato, G. (1984) Macrobiotus sapiens, nuova specie di eutardigrado di Sicilia. Animalia, 11, 85–90.
Binda, M.G. & Pilato, G. (1995) Remarks on tardigrades from the Seychelles, with a description of two new species. Tropical Zoology, 8, 1–6.
Binda, M.G. & Pilato, G. (2001) Macrobiotus savai and Macrobiotus humilis, two new species of tardigrades from Sri Lanka. Bollettino delle sedute dell’Accadenia Gioenia di Scienze Naturali Catania, 34, 360, 101–111.
Biserov, V. (1990) On the revision of the genus Macrobiotus. The subgenus Macrobiotus s. str: a new. systematic status of the group hufelandi (Tardigrada, Macrobiotidae). Communication I. Zooogichesky Zhurnal, 69, 5–17. [in Russian]
Biserov, V. (1994) Some tardigrades from the Seychelles with descriptions of three new species. Tropical Zoology, 7, 181–189.
Dastych, H. (1993) A new genus and four new species of semiterrestrial water-bears from South Africa (Tardigrada). Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 90, 175–186.
Fontoura, P., Pilato, G., Lisi, O. & Morais. P. (2009) Tardigrades from Portugal: four new records and description of two new species. Zootaxa (in press).
Kaczmarek, Ł.& Michalczyk, Ł. & Węglarska, B. (2002) Itaquascon mongolicus, a new species of Eutardigrada from Mongolia (Eutardigrada: Hypsibiidae). Genus, 13, 1, 1–3.
Maucci, W. (1972) Tardigradi muscicoli della Turchia. Memorie del Museo Civico di Storia Naturale, Verona, 20, 169–221.
Maucci, W. (1993) Prime notizie su tardigradi “terrestri” del Madagascar con descrizione di tre specie nuove. Bollettino del Museo Civico di Storia Naturale, Verona, 17, 381–392.
Maucci, W. & Durante Pasa, M.V. (1980) Tardigradi muscicoli delle Isole Andamane. Bollettino del Museo Civico di Storia Naturale, Verona, 7, 281–291.
Pilato, G. (1981) Analisi di nuovi caratteri nello studio degli Eutardigradi. Animalia, 8, 51–57.
Pilato, G., Binda, M.G. & Catanzaro, R. (1991) Remarks on some tardigrades of the African fauna with the description of three new species of Macrobiotus Schultze 1834 . Tropical Zoology, 4, 167–178.
Pilato, G., Binda, M.G. & Claxton, S. (2002) Itaquascon unguiculum and Itaquascon cambewarrense: two new species of eutardigrades from Australia. New Zealand Journal of Zoology, 29, 87–93.
Pilato, G., Binda, M.G. & Lisi, O. (2002) Notes on tardigrades of the Seychelles with the description of two new species. Bollettino delle sedute dell’Accademia Gioenia di Scienze Naturali, Catania, 35, 361, 503–517.
Pilato, G., Binda, M.G. & Lisi, O. (2004) Notes on tardigrades of the Seychelles with the description of three new species. Italian Journal of Zoology, 71, 171–178.
Pilato, G., Binda, M.G. & Lisi, O. (2006) Eutardigrada from New Zealand, with descriptions of two new species. New Zealand Journal of Zoology, 33, 49–63.
Pilato, G., Binda, M.G. & Moncada, E. (1999) Itaquascon biserovi, new species of eutardigrade from central Africa. Bollettino delle sedute dell’Accademia Gioenia di Scienze Naturali, Catania, 32, 356, 171–176.
Richters, F. (1904) Arktische Tardigraden. Fauna arctica, 3, 493–508.
Węglarska, B. (1973) Tardigrada in High Tatra localities bare snow with a description of Itaquascon pawlowski sp. n. Vĕstník Československé Společnosti Zoologické, 37, 2, 150–155.