A New Species and Genus of Kraussinidae (Brachiopoda) With a Note on Feeding

Abstract

SUMMARY A new species and genus, Pumilus antiquatus, of kraussinid brachiopod from shallow water, Lyttelton, New Zealand, is described and figured. It is characterized by the possession of a schizolophous lophophore in the adult, supported by both divergent lamellae and spicules: the shell is smooth, less than 5 mm. long and strongly sulcate. The gonad is hermaphrodite. Notes are given on the ciliary feeding mechanism. The affinities of P. antiquatus are briefly discussed: it is placed in the Kraussinidae.

Tentacle muscles in brachiopods: Ultrastructure and relation to peculiarities of life style

“…According to our data, peritoneal and myoepithelial cells form apical cytoplasmic processes that overlap the apical surfaces of neighboring cells and contribute to the transfer of nutrients from peritoneal cells to myoepithelial cells. We also suspect that the tentacle blood vessel, which in all brachiopods extends along the frontal side of the tentacle coelomic canal (Atkins, 1958;Reed & Cloney, 1977;Storch & Welsch, 1976;present data) According to our data for linguliform brachiopods (i.e., for L. anatina and P. atlanticus), the entire blood vessel wall is formed by flattened myoepithelial cells, which is consistent with previously published data on the blood vessel wall in the tentacles of L. anatina (Temereva, 2017); phoronid blood vessels also have a similar structure (Temereva & Malakhov, 2003). In the craniiform brachiopod N.…”

“…They green-cubic myoepithelial cells. ac, amoebocyte; am, abfrontal muscle; ap, apical process; az, abfrontal zone; bv, blood vessel; cc, coelomic canal; cfm, central part of frontal muscle; cr, centriole; dp, digital process; ecm, extacellular matrix; fg, frontal groove; fm, frontal muscle; fr, frontal ridge; gc, Golgi complex; in, inclusion; lat, lateral coelothelium; lfm, lateral part of frontal muscle; lr, lateral ridge; mf, myofilaments; mt, mitochondria; na, nucleus of cell of abfrontal muscle; nb, nucleus of cell of blood vessel wall; nf, nucleus of cells of frontal muscle; pn, peritoneal neurite; TEM, transmission electron microscopy The organization of the tentacle muscles has been previously studied by light microscopy in rhynchonelliform brachiopods, that is, in the terebratulids Macandrevia cranium (Atkins, 1959a), Platidia anomioides (Atkins, 1959b), Terebratalia transversa (Atkins, 1959с), Pumilus antiquatus (Atkins, 1958), and Megerlia truncata (Atkins, 1961), and in the rhynchonellid Notosaria nigricans (Atlins, 1963;Hoverd, 1985); in the craniiform N. anomala (Blochmann, 1892;Atkins & Rudwick, 1962); and in the linguliform L. anatina (Chuang, 1956). Histological studies were subsequently improved with ultrastructural investigations (TEM) of the structure of the tentacles of L. anatina (Storch & Welsch, 1976;Temereva, 2017), T. transversa (Reed & Cloney, 1977), and Hemithiris psittacea .…”

“…The functional morphology of the tentacles with the muscular system of the first type has been described by Atkins (1958) and Reed and Cloney (1977) for terebratulids. In terebratulids, which have the plectolophous and schizolophous lophophores, the tentacles are extended during filtration (Atkins, 1958;Rudwick, 1970). nective tissue that surrounds the coelomic canal, enables the organism to extend the tentacles for a long time during filtration.…”

Observations on the ciliary feeding mechanism of the brachiopod Crania anomala

“…During late schizolophous and early spirolophous stages two inhalant streams enter the anterolateral regions of the gape: each flows towards the bottom of each bell-shaped brachium and filters past the cirri to escape as exhalant current laterally and anteriorly as in Pumilus (Atkins, 1958).…”

Lenticellaria and Hillerella, new kraussinoid genera (Kraussinoidea, Brachiopoda) from Indo-Pacific and Red Sea waters: evolution in the subfamily Megerliinae

“…Their respective contributions have been summarized by Hiller et al (2008) who published an exhaustive synthesis of the most current knowledge in the field of the Kraussinoidea. The superfamily is represented by one family, the Kraussinidae Dall, 1870 which comprises four genera: Kraussina Davidson in Suess, 1859, Megerlia King, 1850, Megerlina Eudes-Deslongchamps, 1884 and Pumilus Atkins, 1958. The diagnoses of these genera are described in and important characters are emphasised in Hiller et al (2008).…”