Acropora kenti (Brook, 1892)

Bridge, Tom C. L., Cowman, Peter F., Quaưrini, Andrea M., Bonito, Victor E., Frederic, Harii, Head, Catherine E. I., Hung, Julia Y., Halafihi, Tuikolongahau, Rongo, Teina & Baird, Andrew H., 2024, A tenuis relationship: traditional taxonomy obscures systematics and biogeography of the ‘ Acropora tenuis’ (ºcleractinia: Acroporidae) species complex, Zoological Journal of the Linnean Society 202 (1), pp. 1-24 : 19

Acropora kenti (Brook, 1892) status revised

Madrepora kenti Brook 1892: 458 ; Brook 1893: 110, plate 11, fig.B.

Acropora kenti (Brook) ; Wells 1954: 493.

Here removed from synonymy with Acropora tenuis (Dana, 1846) contra Veron and Wallace 1984; 279. See also Cooke et al. 2020; Mattias et al. 2022.

Specimens examined: Madrepora kenti lectotype: NHM 1892.6.8.202 , Thursday Island , Torres Strait, Australia ; syntype: NHM: 1892.6.8.203 , Low Woody Island , GBR, Australia; MTQ: G27054, G27078, G27236, G27245, G27280, G27281, G27282, G27284, G27285, G27286, G27287, G27288, G27289, G27292, G27298, G27711, G28444, G29061, G29064, G29899, G29903, G29905, G31175, G32447, G32448, G32455, G32456, G34149, G35014, G35015, G35138, G35139, G35140, G35141, G35142, G35638, G35879, G40909, G41100, G41101, G41102, G41103, G48325, G49331, G58409, G78648, G78750, G78778, G80247, G80266*, G80256, G80256, G78750, G335181, G335182 GBR; G35638, G35897, G53273, G53275, G53281, G53284, G53288, G78014; G78046, G78064, G80270 , Papua New Guinea; G27291 , G28448 , G35879 , G60564 , G63895 , G80258 Coral Sea ; G60131 , G80251 , G80250 Lord Howe Island .

Description: Corallum horizontal or corymbose, main branches 2.0– 2.5 cm thick. Corallites large, round, appressed tubular. Radial corallites appressed tubular, crowded and prominent, with the outer part of the wall forming a rounded lip with no inner wall. Septa moderately developed, with two directive septa prominent.

Remarks: The lectotype of A. kenti (Supporting Information, Fig. S3) differs from the holotype of A. tenuis in having thicker branches that lack tertiary branching and incipient axials, and in possessing cochleariform radial corallites arranged in neat rows. Of the specimens sequenced in this study, G80266 from Great Detached Reef and G80247 from Myrmidon Reef most closely resemble the lectotype, NHM 1892.6.8.202, designated by Wallace (1999) from Thursday Island, Torres Strait. Brook’s syntype, NHM 1892.6.8.203, from Low Woody Island near Cooktown in the northern GBR is morphologically similar to the lectotype and is almost certainly the same species. Like A. tenuis , the specimens of A. kenti in our phylogeny show considerable variation in gross morphology, in terms of both branch thickness and the neatness of the radial corallites. Two colonies collected adjacent to each other at Myrmidon Reef, GBR, and sequenced in the present series, G80247 and G78778, demonstrate the range of variation in the length and neatness of the radial corallites. Specimens also show variation in branch thickness within and between colonies, some of which might be attributable to environmental factors, such as wave exposure. Despite morphological variability within the species, molecular data clearly demonstrate that A. kenti (Brook, 1892) is distinct from A. tenuis (Dana, 1846); therefore, we formally resurrect the former species. Consequently, the species commonly referred to as A. tenuis on the GBR and elsewhere in eastern Australia (sensu Veron and Wallace 1984), including the genome published as A. tenuis from the GBR ( Cooke et al. 2020) is A. kenti . Unlike many published genomes, images were taken of the live colonies from Orpheus Island, GBR, that provided the material for the A. kenti genome. Voucher specimens from these colonies were also deposited in the collection of the Queensland Museum (G335181 and G335182), and the morphology of the specimens closely matches the A. kenti lectotype. Based on the specimens examined here, the geographical range of A. kenti extends from Lord Howe Island north along the GBR to the Bismarck Sea and east to the Coral Sea (Supporting Information, Fig. S6).