Topic
Macrostomida
About: Macrostomida is a research topic. Over the lifetime, 55 publications have been published within this topic receiving 957 citations.
Papers published on a yearly basis
Papers
1 Apr 1976
TL;DR: Ultrastructural characters of the adhesive organs show that the Macrostomida and Haplopharyngida are related, and that the Polycladida, Rhabdocoela, Proseriata, and Tricladida arerelated, andthat these two groups of orders share a common ancestor.
Abstract: Glandular adhesive organs and other structures by which turbellarians attach themselves temporarily to surfaces have been studied by electron microscopy. Adhesive organs in representatives of the turbellarian orders Haplopharyngida, Macrostomida, Polycladida, Rhabdocoela, Proseriata, and Tricladida are composed of three cell types: two gland cell types and a modified epidermal cell type through which the necks of the glands project. One of the gland types is characterized by its dense membrane-bound, 0.2–0.7Μm diameter, secretion granules and is called here theviscid gland on the basis of evidence that it secretes the adhesive substance by which the organs attach to surfaces. The other gland type is characterized by smaller (0.1Μm), less-dense, membrane-bound secretion granules and is called thereleasing gland on the basis of evidence that it secretes a substance by which adhering organs are released from surfaces. The modified epidermal cell is called theanchor cell; it has a well-developed cell web and bears microvilli with fibrous cores surrounding the tips of the gland necks in a collar-like fashion. Adhesive organs that have the two gland types, viscid and releasing glands, are referred to here asduo-gland adhesive organs. Other turbellarians, including orders Nemertodermatida, Acoela, and Lecithoepitheliata, have adhesive glands or other adhesive structures with a morphology unlike that of duo-gland adhesive organs. Ultrastructural characters of the adhesive organs show that the Macrostomida and Haplopharyngida are related, and that the Polycladida, Rhabdocoela, Proseriata, and Tricladida are related, and that these two groups of orders share a common ancestor. The Nemertodermatida, Acoela, and Lecithoepitheliata, with morphologically different adhesive systems, are apparently derived separately from these orders.
143 citations
TL;DR: Two new species of brackish-water Macrostomum (M. zhujiangensis n. sp. and M. baoanensis N. sp.) were described based on samples collected from the littoral zone of the Zhujiang Estuary as discussed by the authors.
Abstract: Two new species of brackish-water Macrostomum ( M. zhujiangensis n. sp. and M. baoanensis n. sp.) were described based on samples collected from the littoral zone of the Zhujiang Estuary. These are the first records of brackish-water Macrostomum from southern China. Macrostomum zhujiangensis n. sp. and M. baoanensis n. sp. differ from other similar species in the length and morphology of the penis stylet. The penis stylet of M. zhujiangensis n. sp. is C-shaped and its distal opening has a beveled edge. The penis stylet of M. baoanensis n. sp. is J-shaped and the distal region is thicker than other parts of the penis stylet. Molecular phylogenetic analysis supports the establishment of the new species.
125 citations
TL;DR: The paper reviews the following systems: body wall, nervous system, protonephridia, parenchyma, digestive system, reproductive system, and includes a summary of the literature, suggesting the existence of three main evolutionary lines within the Turbellaria.
Abstract: The paper reviews the following systems: body wall, nervous system, protonephridia, parenchyma, digestive system, reproductive system, and includes a summary of the literature. New information is presented for the catenulid and neoophoran body wall-construction, the kalyptorhynch proboscis, the catenulid and haplopharyngid protonephridial construction, and the prolecithophoran spermatozoon and female germ cell. Examples of new features, as well as examples of how electron microscopy has clarified the relative position of structures and their substructures are given from the subcellular level to the organization of whole organs. Fine structural features linking different turbellarian orders are summarized. They apparently support Karling’s (1974) latest assessment of the affinities between the turbellarian orders which is based primarily on light histological data, they add the recognition of a special link between the Macrostomida and Haplopharyngida and they suggest the existence of three main evolutionary lines within the Turbellaria.
102 citations
TL;DR: Two new species of marine Platyhelminthes are described from the west coast of Sweden and the first records of fully mature specimens of Microstomum rubromaculatum von Graff, 1882 from Fiskebackskil and a phylogenetic analysis based on the mitochondrial cytochrome oxidase I (COI) gene are presented.
Abstract: Two new species of marine Platyhelminthes, Microstomum laurae sp. nov. and Microstomum edmondi sp. nov. (Macrostomida: Microstomidae) are described from the west coast of Sweden. Microstomum laurae sp. nov. is distinguished by the following combination of characters: rounded anterior and posterior ends; presence of approximately 20 adhesive papillae on the posterior rim; paired lateral red eyespots located level with the brain; preoral gut extending anterior to brain and very small sensory pits. Microstomum edmondi sp. nov. is a protandrous hermaphrodite with a single ovary, single testis and male copulatory organ with stylet. It is characterized by a conical pointed anterior end, a blunt posterior end with numerous adhesive papillae along the rim, and large ciliary pits. The stylet is shaped as a narrow funnel with a short, arched tip. In addition, the first records of fully mature specimens of Microstomum rubromaculatum von Graff, 1882 from Fiskebackskil and a phylogenetic analysis of Microstomum Schmidt, 1848 based on the mitochondrial cytochrome oxidase I (COI) gene are presented.
98 citations
TL;DR: Two new brackish-water species of Macrostomum, collected from the artificial lake in Overseas Chinese Town mangrove wetland, are described based on the morphology of the penis stylet and on a molecular phylogenetic analysis.
Abstract: In this paper, two new brackish-water species of Macrostomum (M. shenzhenensis n. sp. and M qiaochengensis n. sp.) collected from the artificial lake in Overseas Chinese Town mangrove wetland, are described based on the morphology of the penis stylet and on a molecular phylogenetic analysis. M. shenzhenensis n. sp. has an elongate, narrow stylet with torus-shaped distal wall thickening, while M. qiaochengensis n. sp. has a hook-like stylet with a pointed end. Both the 18S and 28S rDNA phylogenetic analyses of M shenzhenensis n. sp. and M qiaochengensis n. sp. support the establishments of these two new species. Finally, categorization of these two new species based on the morphology of sperm and penis stylet, as well as other morphological features of the reproductive system is briefly discussed.
73 citations
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| Year | Papers |
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| 2018 | 1 |
| 2017 | 1 |
| 2016 | 2 |
| 2015 | 3 |
| 2013 | 1 |
| 2012 | 1 |