Nebela gimlii, David Singer, Anush Kosakyan, Amandine Pillonel, Edward A. D. Mitchell & Enrique Lara, 2015

David Singer, Anush Kosakyan, Amandine Pillonel, Edward A. D. Mitchell & Enrique Lara, 2015, Eight species in the Nebela collaris complex: Nebela gimlii (Arcellinida, Hyalospheniidae), a new species described from a Swiss raised bog, European Journal of Protistology 51 (51), pp. 79-85 : 80-83

Nebela gimlii n.sp. Singer and Lara.

The test is wide pyriform or drop-shaped, laterally compressed, with a protruding narrow neck. Two lateral pores are present ca. 1 / 4 from the distance from the pseudostome to the fundus of the test ( Fig. 1 A and B). A variable number of small pores can be seen on SEM images in apparently random positions from near the aperture to the fundus of the test ( Fig. 2 A, B, E and F). The test is colourless or slightly brownish, composed of small particles (likely obtained from preys, e.g. euglyphid testate amoebae), which are covered by a thin layer of organic cement. The aperture is oval in frontal view, slightly curved in lateral view, surrounded by a thin organic collar characteristic of family Hyalospheniidae (Kosakyan et al., 2012) . Dimensions based on 14 individuals: length: 67.7–77.6 μm (mean = 72.8 μm), breadth: 49.7–61.64 μm (mean = 53.9 μm), width of aperture: 17.5–21 μm (mean = 19 μm).

Illustrations and morphological data of the new species are given in Figs. 1 and 2 and Tables 1 and 2.

Ecology

Nebela gimlii was found exclusively in the relatively dry Sphagnum mosses in the forested part of a peat bog (influenced by lateral drainage) and the drained peatland margin a few meters from the base of old peat extraction walls. These habitats are characterised by low pH, moderate moisture and low nutrient content.

Hapantotype

The tests were collected from a Sphagnum sample in a peatland in Le Cachot, Jura Mountains , Switzerland (47 º00' 15.23 ''N, 6 º 39 ' 52.83 ''E). One SEM stub with several specimens is deposited at the Natural History Museum of Neuchâtel (Ref. Nr.: UniNe-EM- 5). COI gene sequences of Nebela gimlii el 3 1 (499 bp) and Nebela gimlii el 3 4 (499 bp) were deposited in GenBank ( Nebela gimlii el 3 1 KP083297 and, respectively, Nebela gimlii el 3 4 KP083298) .

Etymology

The name of this species refers to the name of Gimli, one of the dwarfs in J.R.R. Tolkien’s masterpiece “The Lord of the Rings”, because of its small size (the smallest known member of the Nebela collaris complex) and stout shape. In addition, it has been found abundantly in a forest, and Gimli was unique among his kind to have been travelling in the woods.

gimlii and N. guttata . Min – minimum, Max – maximum, n – number

of individuals examined (measurements in μm).

* Data from Kosakyan et al. (2013).

Note

Nebela gimlii can be confused with Nebela guttata , but clearly differs in the wider shape of the shell and the smaller dimensions of the test ( Table 2). Both species are closely related and differ by 3.7 % on the considered COI fragment. The two sequences of N. gimlii obtained from two different cells share 99.8 % of similarity.

Tables

Table 1. Biometrical characteristics of Nebela gimlii: M – median, SD – standard deviation, SE – standard error of the mean, CV – coefficient of variation, Min – minimum, Max – maximum, n – number of individuals examined (measurements in μm).

Characters	Mean	M	SD	SE	CV	Min	Max	n
Length	72.8	73.23	2.92	0.78	4	67.71	77.61	14
Breadth	53.9	53.12	3.67	0.98	6.81	49.68	61.64	14
Depth	31.4	30.7	1.4	0.37	4.45	30.5	35	14
Aperture width	19	18.71	1.03	0.28	5.45	17.5	21.06	14
Ratio (L/B) Biovolume (104 μm3)	1.4 8.25	1.35 7.82	0.07 1.08	0.02 0.28	5.45 13.12	1.22 6.94	1.5 10.47	14 14

Table 2. Comparison of morphological characters between Nebela

Characters	Nebela gimlii	Nebela guttata *
	(Min/Max) (n = 14)	(Min/Max) (n = 4)
Length	68/78	80/89
Breadth	50/62	53/63
Aperture width	17.5/21	20/21
Ratio (L/B)	1.2/1.4	1.4/1.5