Bringing three new Silurian bryozoan species into the world

February 10th, 2019

I love being part of the scientific process of naming new organisms and placing them into the grand narrative that is the history of life. It is a kind of rescue — retrieving species from oblivion by giving them identities. Carolus Linnaeus, the father of taxonomy, said it well:

The first step in wisdom is to know the things themselves; this notion consists in having a true idea of the objects; objects are distinguished and known by classifying them methodically and giving them appropriate names. Therefore, classification and name-giving will be the foundation of our science.

The bryozoans described in this post are from a project led by my very accomplished bryozoologist friend Andrej Ernst at the University of Hamburg, Germany (above). In the summer of 2015, Andrej and I met up with our colleague Carl Brett (University of Cincinnati) to collect bryozoans from the Lower Silurian (Aeronian) of western New York. My fieldwork was supported by a grant from the Luce Fund at The College of Wooster. We had a very productive time and saw much geology and paleontology, as you can see from these August 2015 blog posts. That fieldwork was followed by Andrej’s prodigious lab work with the bryozoans. The results have now appeared in the Journal of Paleontology.

The abstract: Thirteen bryozoan species are described from the Brewer Dock (Hickory Corners) Member of the Reynales Formation (lower Silurian, Aeronian) at the locality Hickory Corners in western New York, USA. Three species are new: trepostomes Homotrypa niagarensis n. sp. and Leioclema adsuetum n. sp. and the rhabdomesine cryptostome Moyerella parva n. sp. Only one species, Hennigopora apta Perry and Hattin, 1960, developed obligatory encrusting colonies whereas the others produced erect ramose colonies of various thicknesses and shapes: cylindrical, branched, and lenticular. Bryozoans display high abundance and richness within the rock. This fauna is characteristic of a moderately agitated environment with a stable substrate. The identified species reveal paleobiogeographic connections to other Silurian localities of New York as well as Ohio and Indiana (USA) and Anticosti (Canada).

The top photo in this post is one of the new bryozoans, the trepostome Homotrypa niagarensis. The images are from Figure 8, with the caption: (2) branch oblique section, holotype SMF 23.470; (3) rock thin section with transverse and oblique sections of branches, holotype SMF 23.472; scale bars are 3 mm and 5 mm respectively.

Above is the new trepostome Leioclema adsuetum. The image is from Figure 10, with the caption: (1) longitudinal section of exozone showing autozooecia, mesozooecia, and acanthostyles, paratype SMF 23.553; scale bar is 0.5 mm.

This is the third new species, the cryptostome Moyerella parva. The images are from Figure 11, with the caption: (3) longitudinal section of a colony segment with a pointed base and widened proximal part showing medial axis and autozooecia, holotype SMF 23.559; (4) tangential section showing autozooecial apertures, tubules, and tectitozooecia, holotype SMF 23.559; scale bars are 0.5 mm and 0.2 mm respectively.

The paper is about more than these new species, of course. There are other bryozoans assessed, and Carl Brett’s stratigraphy section is magnificent and a new resource for the area. The new taxa, though, are worth celebrating by themselves.

Thank you to Andrej and Carl for being such good colleagues. I hope we return to the Silurian of western New York for more work.

Reference:

Ernst, A., Brett, C.E. and Wilson, M.A., 2019. Bryozoan fauna from the Reynales Formation (lower Silurian, Aeronian) of New York, USA. Journal of Paleontology, doi.org/10.1017/jpa.2018.101.

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