Tectocepheus velatus is one of the most common oribatid species, both in Norway and world-wide. It is a pioneer species, colonizing new areas for example after receding glaciers. It is abundant in different nature types, and most often in soil. Tectocepheus velatus has wide feeding preferences, and eats bacteria, fungi, dead organic matter and living green plants. It reproduces parthenogenetically, females are produced from unfertilized eggs.

Description

Fig. 1. Dorsal view of Tectocepheus velatus, adult.

Adult: The length of the body is 280–371 µm, and the width is 156–263 µm. The color can vary from yellowish brown to dark-brown. The cuticle has characteristic coarse-grained surface (Fig. 1). The prodorsum has a pair of lamellae, which are connected by a thin translamella (looking as a line). Each of the lamellae has a long cusp that is rounded in the front. Bothridial seta has a long stem (about as long as a head) and a club-shaped barbed head. Interlamellar seta is small. In the front of notogaster, between the pteromorphs, there is a distinct pair of dents. Notogaster has 10 pairs of small setae (Weigmann 2006).

Juvenile stages: Larva: body length 164 µm, width 88 µm. Protonymph: body length 210 µm, width 109 µm. Deutonymph: body length 231 µm, width 113 µm. Tritonymph – body length 281 µm, width 147 µm. The color is whitish-light brown. The stem of bothridial setae is relatively shorter than in adults (Fig. 2), and the head of bothridial setae is clavate, bearing small seate. Notogaster has wrinkled cuticle and small setae (Pfingstl and Krisper 2011).

Fig. 2 (left). Dorsal view of Tectocepheus velatus, juvenile.

Fig. 3 (right). Lateral view of the notogaster of Tectocepheus. Notogaster with one pair of dents in Tectocepheus velatus (a), and notogaster with three pairs of dents in Tectocepheus sarekensis (b).

Look-alikes

Fig. 4. Prodorsum and part of notogaster of Tectocepheus velatus.

Tectocepheus velatus is similar to Tectocepheus sarekensis Trägårdh, 1910, but the species differ by the number of dents in the front of notogaster; Tectocepheus velatus has one pair of such dents (marked by arrowhead in Fig. 3), while Tectocepheus sarekensis has three pairs (marked by arrowheads in Fig. 3). Tectocepheus velatus also lacks longitudinal stripes on the prodorsum in the region between the lamellae (Fig. 4), which are present in Tectocepheus sarekensis (Fig. 5) (Weigmann 2006).

Biology

Reproduction is parthenogenetic, only females are present and they are produced from unfertilized eggs. Development time from egg to adult lasts 85 days in 16–20 °C (Chistyakov 1972). Tectocepheus velatus is opportunistic herbo-fungivore, which means that it is able to digest cellulose in litter and cell-walls of living green plants and trehalose in fungi.

Ecology

Distribution

Tectocepheus velatus is cosmopolitan (Subías 2004), it is found world-wide.

Habitat

The species is extremely eurytopic. It occures in many different habitat types and is often numerous. It is found mainly in soils, and is more abundant in upper soil layers (0-3 cm). Tectocepheus velatus can also be found on trees and other plants, on stones, walls, and roofs of buildings.

Findings in Norway

Tectocepheus velatus is very common in Norway and has been found in nearly all our studies, for example in forests, bogs, also in arctic tundra in Svalbard (Solhøy 1979, Hågvar and Abrahamsen 1980, Hågvar and Kjøndal 1981, Thunes et al. 2004). It is a pioneer species and was the first colonizer in the foreland of the receding glacier Hardangerjøkulen in central south Norway (Hågvar et al. 2009). Tectocepheus velatus was also the most abundant oribatid mite in the mosses growing on roofs of buildings in Sogn og Fjordane, with a density of about 400 individuals per 500 cm3 of moss (Graczyk and Seniczak 2013).

References

Chistyakov MP (1972). Postembryonic development of Tectocepheus velatus (Oribatei). Zoologicheskii Zhurnal 51, 604–607.

Graczyk R and Seniczak S (2013). Oribatid mites (Acari: Oribatida) from roofs of houses in Sogn og Fjordane (Norway) Biological Letters, 50(2), 77–85. doi.org/10.2478/biolet-2013-0012

Hågvar S and Abrahamsen G (1980). Colonisation by Enchytraeidae, Collembola and Acari in sterile soil samples with adjusted pH levels. Oikos 34, 245–258.

Hågvar S and Kjøndal BR (1981). Effects of artificial acid rain on the microarthropod fauna in decomposing birch leaves. Pedobiologia 22, 409–422.

Hågvar S, Solhøy T and Mong CE (2009). Primary succession of soil mites (Acari) in a Norwegian glacier foreland, with emphasis on oribatid species. Arctic,. Antarctis and Alpine Research, 41, 219–227. doi.org/10.1657/1938-4246-41.2.219

Pfingstl T and Krisper G (2011). No difference in the juveniles of two Tectocepheus species (Acari: Oribatida, Tectocepheidae). Acarologia 51(2), 199–218. doi.org/10.1051/acarologia/20112005ff. ffhal-01600010f

Solhøy T (1979). Oribatids (Acari) from an oligotrophic mire in western Norway. Fauna Norvegica Ser B 26, 91–94.

Subías LS (2004). Listado sistemático, sinonímico y biogeográfico de los ácaros oribátidos (Acariformes, Oribatida) del mundo (excepto fósiles). Graellsia 60 (número extraordinario), 3–305.

Thunes KH, Skartveit J, Gjerde I, Starý J, Solhøy T, Fjellberg A, Kobro S, Nakahara S, zur Strassen R, Vierbergen G, Szadziewski R, Hagan DV, Grogan Jr WL, Jonassen T, Aakra K, Anonby J, Greve L, Aukema B, Heller K, Michelsen V.,Haenni J-P, Emeljanov AF, Douwes P, Berggren K, Franzen J, Disney RHL, Prescher S, Johanson KA, Mamaev B, Podenas S, Andersen S, Gaimari SD, Nartshuk E, Søli GEE, Papp L, Midtgaard F, Andersen A, von Tschirnhaus M, Bächli G, Olsen KM, Olsvik H, Földvári M, Raastad JE, Hansen LO and Djursvoll P (2004). The arthropod community of Scots pine (Pinus sylvestris L.) canopies in Norway. Entomologica Fennica 15, 65–90.

Weigmann G (2006). Hornmilben (Oribatida). Die Tierwelt Deutschlands. 520 pp. Vol. 76, Goecke and Evers, Keltern.

Siden siteres som:

Seniczak A. Tectocepheus velatus (Michael, 1880). www.artsdatabanken.no/Pages/286332. Nedlastet <dag.måned.år>.