Umimayanthus jebarra, Montenegro & Fromont & Richards & Kise & Gomez & Hoeksema & Reimer, 2024

Umimayanthus jebarra sp. nov.

Montenegro, Kise & Reimer urn:lsid:zoobank.org:act:557A4CDC-8805-4626-854E-C591DB88598C

Etymology. The specific epithet “jebarra ” is derived from the phoneme used to refer to the emu in Wunambal language. This in reference to the elongated shape of the polyps in U. jebarra sp. nov., which resemble the neck of an emu. As well, the name can act as a memorial to all the emus killed during the Great Emu Wars of 1932 in Western Australia. “jebarra anya” n., A-class. emu. Dromaius novaehollandiae . Syn: garnanganyja; jeebarra. See Mangglamarra (1991) and Karadada et al. (2011).

Material examined. Type locality: Eclipse Is. [loc. 21], − 13.493782 °S, 125.851633 °E. Holotype: WAM Z88825 About WAM (− 13.493782 °S, 125.851633 °E, loc. 21, Eclipse Is., Western GoogleMaps

CONTRIBUTIONS TO ZOOLOGY 93 (2024) 466–522

Australia, 41 m depth, March 2, 2016 by O.A. Gomez & J.A. Ritchie). No other material was available.

Diagnosis. U. jebarra sp. nov. can be distinguished from other species in the genus Umimayanthus by having colonies with polyps connected to each other in a linear fashion, and establishing symbiotic associations with sponges in the genus Endectyon . Additionally, three unique substitutions in the ITS-rDNA region differentiate U. jebarra sp. nov. from all other species in the genus Umimayanthus , as follows: “G” in position 367 bp, “C” in position 417 bp and “A” in position 760 bp. Furthermore, a unique combination of nucleotides can be found between positions 417 bp to 425 bp in the ITS-rDNA region ( fig. 10).

Description. Size. Preserved polyps were on average 2.34 mm ± 0.02 mm (σ2 = 0, max. 2.36 mm, n = 3 polyps) in diameter, and 3.09 mm ± 0.63 mm (σ2 = 0.39, max. 3.77 mm, min. 2.53, n = 3 polyps) in height. All measurements were performed on ethanol- preserved specimens: zoantharian voucher WAM Z88825.

Morphology. The holotype specimen is associated with a sponge in the genus Endectyon . The colony is formed by a chain of polyps that branches and extends linearly over the surface of the sponge. The coenenchyma connecting the polyps is thin but clearly visible. All polyps were clearly spread over the sponge matrix and the coenenchyma tissue by 3.09 mm ± 0.63 mm on average. Capitulary ridges were visible, and approximately 16 in number. Polyps preserved in ethanol were orange in colour. No cnidae or internal morphological data are available for this species due to the poor condition of the preserved specimen.

Distribution. The specimen analysed was collected along the west coast of Australia. Eclipse Is. [loc. 21] ( fig. 1). The specimen was found at a depth of 41 m.

CONTRIBUTIONS TO ZOOLOGY 93 (2024) 466–522

CONTRIBUTIONS TO ZOOLOGY 93 (2024) 466–522

Associated host. Umimayanthus jebarra sp. nov. was found in association with a sponge in the genus Endectyon .

Remarks. U. mirnangga sp. nov., U. wunanggu sp. nov., and U. jebarra sp. nov. are closely related sibling species. Nonetheless, key diagnostic molecular and morphological characters, including the external morphology of the colonies and the height of the polyps, as well as the different host species, clearly separate these three species from each other.

The sponge specimen voucher WAM Z94791 could only be identified as Endectyon sp. The acanthostyles are “cladotylote- like”. For now, we have retained this specimen in Endectyon but this interest- ing specimen requires further study for a species- level identification.

While no other species in the genus Umimayanthus quite resemble U. jebarra sp. nov., the closest similarity is to one of the specimens WAM Z88817 of U. mirnangga sp. nov. associated with the sponge Endectyon (Endectyon) fruticosum (sponge voucher WAM Z87200). However, the polyps of U. mirnangga sp. nov. are solitary, while the polyps of U. jebarra sp. nov. are clearly connected to each other in a linear fashion by a coenenchyma, which is not as well developed as in U. cf. aruensis or in U. discolor sp. nov.