Abstract
Scutovertex arenocolus spec. nov. living in the sandy shore of the Baltic coast is described. Additionally, a closely related species, S. pilosetosus, occurring in marsh habitats of the North Sea coast, is redescribed in detail. Both species show a similar habitus. Scutovertex arenocolus differs from S. pilosetosus in the length of body, cusps and notogastral setae, in the ridge on mentum as well as in a different exochorion structure of the eggs. A morphometric analysis of 14 morphological characters confirmed distinctly shorter cusps and notogastral setae in S. arenocolus. Additionally, a principal component analysis performed with 17 morphological traits provided a clear separation of these two species and of S. minutus. The results of these analyses lead to the conclusion that earlier reports of S. minutus in the coastal zone of the Atlantic, the Baltic and the North Sea should be assigned to the one or the other of these two littoral species.
References
Dalenius, P. (1950) The Oribatid fauna of South Sweden with remarks concerning its ecology and zoogeography. Kungliga Fysiografiska Sällskapets I Lund Förhandlingar, 20, 1–19.
Gil, J. & Subias, L.S. (1990) Oribatidos del cabo de San Vicente (Portugal) (Acari, Oribatida). Boletin de la Asociacion espanola de Entomologia, 14, 137–151.
Gjelstrup, P. & Søchting, U. (1979) Cryptostigmatic mites (Acarina) associated with Ramalia siliquosa (Lichenes) on Bornholm in the Baltic. Pedobiologia, 19, 237–245.
Hammer, O., Harper, D.A.T. & Ryan, P.D. (2001) PAST: Palaeontological Statistics software package for education and data analysis. Palaeontologia Electronica, 4, 9pp.
Karppinen, E. (1971) Studies on the Oribatei (Acari) of Norway. Annales Entomologici Fennici Soumen, 37, 30–53.
Koch, C.L. (1836) Cepheus minutus. Deutschlands Crustaceen, Myriapoden und Arachniden, Heft 3, Tab. 12.
Krisper, G., Pfingstl, T. & Ebermann, E. (2008) SEM-Investigations on the exochorion of scutoverticid eggs. Soil Organisms, 80, 217–221.
Luxton, M. (1966) The Acarine fauna of Blakeney Point, Norfolk. Annals and Magazine of Natural History (Ser. 13), 9, 519–530.
Michael, A.D. (1879) A contribution to the knowledge of the British Oribatidae. Journal of the Royal Microscopic Society, London, 2, 225–251.
Minguez, M.E. & Subias, L.S. (1986) Nuevos Oribatidos (Acari, Oribatida) de las islas Columbretes (España). Cuadernos de Investigación Biológica (Bilbao), 9, 75–88.
Monson, F.D. (1998) Oribatid mites (Acari: Cryptostigmata) from Slapton Wood and the vicinity of Slapton Ley. Field Studies, 9, 325–336.
Niemi, R. (1995) Oribatid species (Acari, Oribatida) new to the fauna of Finland. Entomologica Fennica, 5, 213–217.
Pfingstl, T., Schäffer, S., Ebermann, E. & Krisper, G. (2008) Intraspecific morphological variation of Scutovertex sculptus Michael (Acari: Oribatida: Scutoverticidae) and description of its juvenile stages. Zootaxa, 1829, 31–51.
Polderman, P.J.G. (1977) Scutovertex pilosetosus nov. spec. from the Netherlands (Acari, Oribatida). Entomologische Berichten, Amsterdam, 37, 129–132.
Schäffer, S. & Krisper, G. (2007) Morphological analysis of the adult and juvenile instars of Scutovertex minutus (Acari, Oribatida, Scutoverticidae). Revue Suisse de Zoologie, 114, 663–683.
Schuster, R. (1966) Hornmilben (Oribatei) als Bewohner des marinen Litorals. Veröffentlichungen des Institutes für Meeresforschung Bremerhaven, SoBd. 2, 319–327.
Weigmann, G. (1973) Zur Ökologie der Collembolen und Oribatiden im Grenzbereich Land-Meer (Collembola, Insecta – Oribatei, Acari). Zeitschrift für wissenschaftliche Zoologie, 186, 295–391.
Weigmann, G. (2006) Hornmilben (Oribatida). Die Tierwelt Deutschlands, begründet 1925 von Friedrich Dahl. 76. Teil. Goecke & Evers, Keltern, 520 pp.
Weigmann, G. (2008) Oribatid mite communities in atlantic salt marshes: an ecological and biogeographical comparison between German and Portuguese sea shores. In: Bertrand, M., Kreiter, S., McCoy, K.D., Migeon, A., Navajas, M., Tixier, M.-S. & Vial, L. (Eds), Integrative Acarology, Proceedings of the sixth Congress of the European Association of Acarologists, Creative Commons-BY-NC-ND, Compact Disc ISBN 978-2-9532656-0-6, Montpellier 2008, pp. 275–283.
Weigmann, G. (2009) Oribatid mites (Acari: Oribatida) from the coastal region of Portugal. III. New species of Scutoverticidae and Scheloribatidae. Soil Organisms, 81, in press.