Cultroribula bicultrata is found in the Holarctic. In Norway it was first found in 2019, in a wet broadleaf forest. It is characteristic of organic layers of acidic forest soils. It reproduces parthenogenetically, only females are present and they are produced from unfertilized eggs.


Adult: The body length is 225–250 µm, and width is 135 µm. The color is light to dark brown. It has legs with one claw. Rostrum is prolonged (stretched forward) and has three long teeth (Fig 1). The lamellar cusps are long, slender, rounded. Interlamellar setae is very short and fine. Bothridial seta has a long stalk and a spindle-like head. Notogaster bears 10 pairs of very short to vestigial setae (Bernini 1969, Weigmann 2006). 

Juvenile stages: unknown.

Fig. 1. Dorsal view of Cultroribula bicultrata, adult.

Fig. 2. Dorsal view of Cultroribula juncta, adult.


It is similar to Cultroribula juncta (Michael, 1885), but has three long teeth on the rostrum (Fig. 1), while Cultroribula juncta (Fig. 2) has three short teeth. It has legs with one claw, while Cultroribula juncta has three claws (two side claws are thinner than the middle claw). Bothridial seta of Cultroribula bicultrata has a long stalk and a spindle-like head, and this of Cultroribula juncta has a short stalk and a thick spindle-like head (Weigmann 2006).


The reproduction is parthenogenetic (Maraun et al. 2019), only females are present and they are produced from unfertilized eggs. Its development and feeding preferences have not yet been studied.



The distribution of Cultroribula bicultrata is holarctic, it is frequent in the Palearctic, and it is also known from the Indonesian island Java (Subías 2004).


It is a characteristic species of organic layers of acidic forest soils (Weigmann 2006).

Findings in Norway

The species was first found in Norway in 2019. It was found in dead wood in a wet forest in Western Norway. The forest was a mixture of low-herb forest and riparian forest adjacent to a fast-flowing stream. Among ca. 6000 oribatid mite specimens examined from this forest only one adult specimen of Cultroribula bicultrata was found (Seniczak 2019).


Bernini F (1969). Notulae Oribatologicae I. Contributo alla conoscenza degli Oribatei (Acarida) della Pineta dei S. Vitale (Ravenna). Redia, 51, 329–375.

Maraun M, Caruso T, Hense J, Lehmitz L, Mumladze L, Murvanidze M, Nae I, Schulz J, Seniczak A and Scheu S (2019). Parthenogenetic vs. sexual reproduction in oribatid mite communities. Ecology and Evolution 9(12), 7324–7332.

Seniczak A, Bolger T, Roth S, Seniczak S, Djursvoll P and Jordal BH (2019). Diverse mite communities (Acari: Oribatida, Mesostigmata) from a broadleaf forest in western Norway. Annales Zoologici Fennici 56(1), 121-136.

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

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

Siden siteres som:

Seniczak A. Cultroribula bicultrata (Berlese, 1905). Nedlastet <dag.måned.år>.