Laimella Cobb 1920

Genus Laimella Cobb, 1920 Emended diagnosis. Sabatieriinae with striate cuticle; fine punctations may be also observed. Anterior and posterior cephalic sensilla closely spaced, posterior setae usually longer than anterior. Buccal cavity small, three small teeth may appear as weak cuticularisation at...

Full description

Bibliographic Details
Main Authors: Barnes, Natalie, Kim, Hyeong Geun, Lee, Wonchoel
Format: Text
Language:unknown
Published: Zenodo 2012
Subjects:
Online Access:https://dx.doi.org/10.5281/zenodo.5254029
https://zenodo.org/record/5254029
Description
Summary:Genus Laimella Cobb, 1920 Emended diagnosis. Sabatieriinae with striate cuticle; fine punctations may be also observed. Anterior and posterior cephalic sensilla closely spaced, posterior setae usually longer than anterior. Buccal cavity small, three small teeth may appear as weak cuticularisation at base of anterior buccal cavity. Spicule simple arcuate, gubernaculum with posteriorly directed paired apophyses. Supplements minute or absent. Tail elongate, posterior section filiform. Remarks. Presently, there are 7 species of Laimella recognised as valid species; L. filipjevi Jensen 1979, L. minuta Vitiello 1970, L. longicauda Cobb 1920 and L. vera Vitiello 1970 (following the revision by Jensen (1979)), and L. annae Chen & Vincx, 2000, L. sandrae Chen & Vincx, 2000 and L. subterminata Chen & Vincx, 2000, described by Chen & Vincx (2000). Two species formerly described as belonging to Laimella have been reclassified as Paracomesoma ( P. quadrisetosum and P. hexasetosum , both B. Chitwood (1937)), and a third species reclassified as Paramesonchium ( P. serialis Wieser 1954) all by Jensen (1979). However, Jensen (1979) also undertook a number of synonimisations, specifically: 1. Laimella filipjevi nom. nov., pro Laimella longicaudata , syn. Sabatieria longicaudata Filipjev 1922. 2. L. longicauda Cobb 1920, syn. L. filicaudata Ward 1974. Laimella filipjevi has been recently re-examined by Tchesunov (2000) who additionally recorded the species in the White Sea. However, the current authors believe that the reasons given to refer L. filicaudata to the status of junior synonym of L. longicauda are not valid: The description of L. filicaudata and the differences listed therein between this species and L. longicaudata are well defined (Ward 1974). Namely, relative tail length (11.2 vs 17.7 abd, L. filicauda and L. longicauda respectively), proportion of tail cylindrical (81 % vs 66 %) and relative lengths of the cephalic setae (R2:R3 = 1:3 vs 1:4). Laimella filicaudata Ward, 1974 is therefore reinstated here. Published descriptions of these now eight known species of Laimella differ in the morphological characters considered of note, but reviewing these species the relative body proportions, including the de Man’s ratios, are particularly important. Therefore Table 1 presents a comprehensive comparison of the morphometric measurements of these species and Table 2 provides the calculated body proportions, such as de Man's ratios. Where measurements were not presented in the original publications they are supplemented by measurements made by the authors from the original published figures where possible. : Published as part of Barnes, Natalie, Kim, Hyeong Geun & Lee, Wonchoel, 2012, New species of free-living marine Sabatieriinae (Nematoda: Monhysterida: Comesomatidae) from around South Korea *, pp. 263-290 in Zootaxa 3368 (1) on pages 265-268, DOI: 10.11646/zootaxa.3368.1.14, http://zenodo.org/record/5252511 : {"references": ["Cobb, N. (1920) One hundred new nemas. Contribution To A Science of Nematology (Baltimore) 9, 217 - 343.", "Jensen, P. (1979) Revision of Comesomatidae (Nematoda). Zoologica Scripta, 8 (2), 81 - 105.", "Vitiello, P. (1970) Nematodes libres marins des vases profondes du golfe du lion 2 Chromadorida. Tethys, 2 (2), 449 - 500.", "Chen, G. & Vincx, M. (2000) Nematodes from the Strait of Magellan and the Beagle Channel (Chile): the genera Cervonema and Laimella (Comesomatidae: Nematoda). Hydrobiologia, 427, 27 - 49.", "Chitwood, B. (1937) A new genus and ten new species of marine nematodes from North Carolina. Proceedings of the Helminthological Society of Washington, 4 (2), 54 - 59.", "Wieser, W. (1954) Free-living marine nematodes 2. Chromadoroidea. Reports of the Lund University Chile Expedition 1948 - 49, 17, Lund University, Lund 148 pp.", "Filipjev, I. (1922) Encore sur les Nematodes libre de la Mer Noire. Acta Instituti Agronomici Stauropolitani, 1 (16), 83 - 184.", "Ward, A. R. (1974) Three new species of free-living marine nematodes from sublittoral sediments in Liverpool Bay. Marine Biology, 24, 93 - 96.", "Tchesunov, A. (2000) Several new and known species from the families Coninckiidae and Comesomatidae (Nematoda) in the White Sea. Hydrobiologia, 435 (1 - 3), 43 - 59."]}