Stenostomum grande Child 1902

• Main Authors: Noreña, Carolina, Damborenea, Cristina, Brusa, Francisco
• Format: Text
• Language: unknown
• Published: Zenodo 2005
• Subjects: Biodiversity; Taxonomy; Animalia; Platyhelminthes; Catenulida; Gentianales; Stenostomidae; Stenostomum; Stenostomum grande; Kola Peninsula; Argentina; Hess; Brusa; kola peninsula
• Online Access: https://dx.doi.org/10.5281/zenodo.5113607; https://zenodo.org/record/5113607

Stenostomum grande Child, 1902 (Fig. 2B) Stenostomum oesophagium Kepner & Carter, 1931 Description : Single specimens 1–2 mm long, two- to six-zooid chains up to 6 mm long. Body cylindrical, anteriorly rounded. Dorso-lateral ciliated pits longitudinally elongated. Constriction at the level of the oral pore. Posterior end with an intestine-lacking region. Heterogeneous ciliated epithelium, with scarce semirigid sensory cilia. Dorsal epidermis with rhabdites arranged perpendicularly in rosettes. The rhabdites are parallel to the surface in the ventral epidermis, where three longitudinal lines without rhabdites can be seen. Colour in life whitish. From the apical end to the brain, the epidermis bears compact rhabdites giving it a darker colour. Anterior brain lobes deeply dentate. A pair of lightrefracting bodies type 1 associated with the posterior lobes. Dilatable, semicircular oral pore. Pharynx occupying 1/5–1/6 of body length. Pharyngeal glands (type a) in the anterior half. Transition between pharynx and intestine with a narrow sphincter. Excretophores irregularly distributed along the intestine. Nephridiopore proximal to the terminal end. Distribution : Chicago (Child, 1902), Illinois and New York (Graff, 1913), Pennsylvania (Kepner & Carter, 1931), and Virginia (Nuttycombe & Waters, 1938; Kolasa, 1991), USA; southern Finland (Nassonov, 1924); Kola Peninsula (Nassonov, 1925); St Petersburg (Leningrad) (Nassonov, 1926); São Paulo and Paraná State, Brazil (Marcus, 1945b); near Onverwacht, Surinam (Van der Land, 1970); Konin Lakes, Poland (Kolasa, 1977). Los Talas, Berisso, Buenos Aires, Argentina, October 1998 to April 1999 and March 2000. This species has not been previously recorded in Argentina. Stored material : Ten sagittally sectioned specimens in the CHMLP. No. 5304. Discussion : Marcus (1945a) indicates two forms: ‘typica’ which corresponds to Child’s (1902) description and ‘megista’ for the specimens coming from Tieté River, São Paulo, Brazil. The difference between these forms is based on body size, brain development, arrangement of the rhabdites and colouring of the pharynx. The specimens from Berisso, Buenos Aires, correspond to the form ‘typica’. Mature forms of this species have been recognized. Nuttycombe & Waters (1938) and Marcus (1945b) observed specimens with an unpaired testis at the level of the pharynx and Kepner et al . (1933) found mature female gonads. : Published as part of Noreña, Carolina, Damborenea, Cristina & Brusa, Francisco, 2005, A taxonomic revision of South American species of the genus Stenostomum O. Schmidt (Platyhelminthes: Catenulida) based on morphological characters, pp. 37-58 in Zoological Journal of the Linnean Society 144 (1) on pages 44-46, DOI: 10.1111/j.1096-3642.2005.00157.x, http://zenodo.org/record/4634680 : {"references": ["Child CM. 1902. Studies on regulation. Archiv fur Entwicklungsmechanik der Organismen 15: 187 - 234, 355 - 422.", "Kepner WA, Carter J. 1931. Ten well-defined new species of Stenostomum. Zoologischer Anzeiger 93: 108 - 123.", "Graff L. 1913. Turbellaria. II. Rhabdocoela. Das Tierreich. Konigliche Preussische Akademie der Wissenschaften zu Berlin 20: 1 - 147.", "Nuttycombe J, Waters A. 1938. The American species of the genus Stenostomum. American Philosophical Society 79: 213 - 301.", "Kolasa J. 1991. Flatworms: Turbellaria. In: Thorp JM, Covich AP, eds. Ecology and classification of North American freshwater invertebrates. New York: Academic Press, 145 - 171.", "Nassonov N. 1924. Les trats generaux de la distribution geographique des Turbellaria rhabdocoelida dans la Russie, etc. Bulletin de l'Academie des Sciences de Russie 1924: 327 - 352.", "Nassonov N. 1925. La faune des Turbellaria de la peninsule de Kola. Bulletin de l'Academie des Sciences de l'Union ses Republiques Sovietiques Socialistes 1925: 53 - 74.", "Nassonov N. 1926. Die Turbellarienfaunades Leningrader Gouvernements I. Bulletin de l'Academie des Sciences de l'Union des Republiques Sovietiques Socialistes 1926: 817 - 836.", "Marcus E. 1945 b. Sobre Microturbelarios do Brasil. Comunicaciones Zoologicas del Museo de Historia Natural de Montevideo 1 (25): 1 - 74. Est I - XI.", "Van der Land J. 1970. Kleine Dieren Uit Het Zoete Water Van Suriname Verslag Van Een Onderzoek In 1967. Zoologische Bijdragen 12: 1 - 46.", "Kolasa J. 1977. Turbellaria and Nemertini. Bottom fauna of the heated Konin lakes. Monografie Fauny Polski 7: 27 - 46.", "Marcus E. 1945 a. Sobre Catenulida brasileiros. Boletins da Facultade de Filosofia, Ciencias e Letras Zoologia 10: 3 - 133.", "Kepner WA, Carter J, Hess M. 1933. Observation upon Stenostomum oesophagium. Biological Bulletin 64: 405 - 417."]}