Ultrastructure and function of the mastax in Dicranophorus forcipatus (Rotifera: Monogononta)

Abstract

Rotifers are characterized by a complex set of cuticularized jaw elements in the pharynx. The fine structure of the jaw elements has been the subject of SEM studies for some time, but only very limited information exists on the ultrastructure of the jaw elements and their function beyond taxonomic considerations. Drawing on SEM and TEM techniques, the present study presents a detailed analysis of the mastax in Dicranophorus forcipatus, a carnivorous monogonont rotifer species from freshwater habitats characterized by an extrusible, grasping jaw apparatus. Based on ultrathin serial sections, the jaw elements are reconstructed and, in total, nine paired and two unpaired muscles identified. Possibly homologous muscles in other rotifer species are discussed and functional considerations of the forcipate mastax are suggested.

The ultrastructure of the mastax of Filinia longiseta (Flosculariaceae, Rotifera): Informational value of the trophi structure and mastax musculature

“…3C; white arrowhead) -we found cuticular tubes in the ultrastructure of the fulcrum (Pleurotrocha petromyzon and Proales tillyensis (see Wulfken et al, 2010), Bryceella stylata (see Wilts et al, 2010), Dicranophorus forcipatus (see Riemann and Ahlrichs, 2008), Paraseison annulatus, and S. nebaliae (see Ahlrichs, 1995b). In all of these species, except for F. longiseta, P. annulatus and S. nebaliae, the cuticular tubes are restricted to the fulcrum region.…”

“…: musculus hypopharyngeus, Ahlrichs, 1995b; musculus fulcro mucosus, Dehl, 1934;dépresseure de piston, De Beauchamp, 1909). While the mastax receptor retractor is usually located in the so-called 'piston' which frontally terminates in the mastax receptor (see Riemann and Ahlrichs, 2008;Wulfken et al, 2010), F. longiseta displays neither a piston nor a mastax receptor located between the rami (Fig. 3A-C).…”

“…7, box 7). In all of our formerly investigated ploimid species (D. forcipatus, Riemann and Ahlrichs, 2008;B. stylata, Wilts et al, 2010;P.…”

A review of potential methods for zooplankton control in wastewater treatment High Rate Algal Ponds and algal production raceways

“…can graze the individual cells of small-celled colonies (e.g., Dictyosphaerium spp.) [76][77][78]. The species composition of rotifers in natural systems is commonly associated with the concentration of nutrients (i.e., trophic state) [79,80].…”

Ontogeny of the jaws of monogonont rotifers: the malleate trophi of Rhinoglena and Proalides (Ploima, Epiphanidae)

“…); in Bryceella stylata (Wilts et al. ); in Dicranophorus forcipatus (also in the epipharynx) (Riemann & Ahlrichs ); in the ploimid monogononts, Encentrum mustela , Itura aurita , Lindia tecusa, and Asplanchna (Wulfken & Ahlrichs ); and in the flosculariacean monogonont Filinia longiseta (Wulfken & Ahlrichs ). This suggests that the distinctly rod‐shaped sclerites (without sulcus and carina) composing the fulcrum in Rhinoglena and Proalides , and likewise catenae in the latter, have a tubular structure with electron‐dense core as well.…”