Lateothela, Moore & Alderslade & Miller, 2017

Moore, Kirrily M., Alderslade, Philip & Miller, Karen J., 2017, A taxonomic revision of Anthothela (Octocorallia: Scleraxonia: Anthothelidae) and related genera, with the addition of new taxa, using morphological and molecular data, Zootaxa 4304 (1), pp. 1-212 : 94-95

Lateothela gen. nov. Moore, Alderslade & Miller

http://zoobank.org/45E8D773-D627-45BC-A604-F6FCD829309B

Diagnosis: Monomorphic scleraxonians which form bulky, complex colonies; often with an extensive membranous or encrusting growth, from which multiple, upright, robust branches may emanate; some secondary branching can occur along with anastomoses; medulla without well-defined coelenteric canals; ring of boundary canals encircling medulla, clearly defining the cortex; distinct, robust calyces with a smooth mat-like surface; sclerites include tuberculate sticks and spindles, rodlets and spiky clubs; preponderance of short, stout warty rodlets in calyces and surface; longitudinally arranged tuberculate sticks and spindles and spiky clubs in the tentacle rachis; thorny josephinae clubs crowded and longitudinally arranged in the pinnules.

Type species: Parerythropodium grandiflorum Tixier-Durivault & d'Hondt, 1974 by designation and monotypy.

= Lateothela grandiflora new combination

Remarks: Morphologically comparable genera include Anthothela , Victorgorgia and Briareopsis Bayer, 1993 . Specimens of Lateothela n. gen. have been mistakenly identified as Anthothela grandiflora for over 150 years. Superficially the colonies are similar with a complex construction of both encrusting and branched forms, similar colour and habitat and comparable appearance of calyces and polyps.

The main features of Lateothela n. gen. which differ from those of Anthothela are: preponderance of short, stout, warty rodlets in the cortex and calyx ( Anthothela specimens chiefly have tuberculate sticks and spindles); many thorny josephinae clubs in pinnules and tentacle rachis, few or no flat spatulate clubs ( Anthothela specimens have many spatulate clubs and few or no josephinae clubs); crowded mixed sclerite forms on the polyp neck and tentacle rachis that include spiky clubs ( Anthothela specimens have only sparse tuberculate sticks and spindles on the polyp neck and tentacle rachis).; colony robust, with a tendency for multiple branches to grow roughly perpendicular from a membrane with only minor secondary branching or anastomosing ( Anthothela specimens have many narrow, tangled, commonly anastomosing branches growing without any discernable organisation). The main features of Lateothela n. gen. which differ from those of Victorgorgia are: thorny josephinae clubs in the tentacles ( Victorgorgia has josephinae clubs which lack thorns and have only small, rounded tubercles); no central coelenteric canals in the medulla ( Victorgorgia has clearly defined central coelenteric canals in the medulla); growth form not aborescent ( Victorgorgia has arborescent colonies); sclerites present in the pharynx ( Victorgorgia species lack pharynx sclerites). Lateothela n. gen. could be compared to Briareopsis due to a similarity of sclerites but Briareopsis has a distinct single main stem which then branches dichotomously, the cortex is divided into two layers (the inner layer is very spongy), the medulla and cortex are only poorly differentiated by boundary canals and the calyces are very low ( Bayer 1993).

Lateothela n. gen. actually appears to be relatively common in the northern eastern Atlantic , especially around Norway and in the north western Atlantic along the North American continental shelf (Scott France, pers. comm.), and can form large and extensive colonies, however its true identity has remained overlooked due to the erroneous assumption it was Anthothela grandiflora . The type species of Lateothela n. gen., Parerythropodium grandiflorum Tixier-Durivault & d'Hondt, 1974 (currently known as Alcyonium grandiflorum ) was described as a membranous colony, and more recently other membranous colonies were identified by Stokvis & Ofwegen (2006) as Alcyonium grandiflorum . There is a possibility that many specimens from Lateothela n. gen. have been collected as membranous colonies only, presumably prior to the formation of branches with a medulla, and thus not associated with the scleraxonia . In fact, Stokvis & van Ofwegen (2006) describe a number of Alcyonium species which are all membranous and have similar sclerites to Lateothela n. gen.. In particular, some of the specimens have thorny josephinae clubs in the pinnules and tentacles as well as the short, stout, tuberculate rods and short clubs in the calyx and cortex. Both morphological and molecular characters of Lateothela n. gen. appear to be very similar to that of some nominal Alcyonium species, and these intricately entwined relationships are worthy of further investigation.

The genus is placed tentatively in the family Anthothelidae with the knowledge that the family as currently recognised ( Williams & Cairns 2015) is polyphyletic ( Cairns & Wirshing 2015), and the phylogenetic position of Lateothela n. gen. is entwined with some nominal Alcyonium (Alcyoniidae) species. It is possible that Lateothela n. gen. and some of these nominal Alcyonium species form a family separate from Anthothelidae and Alcyoniidae but this decision requires a revision of both families. Given that L. grandiflora n. comb. differs significantly, morphologically and genetically, from the type species of Alcyonium ( A. digitatum Linnaeus ) it was thought that it is unlikely to be considered a true Alcyoniidae and for the species to be placed in Alcyoniidae would require a significant broadening of the diagnosis of the family. The gross morphological characterisitics, chiefly the scleraxonian axis and colony formation place the genus within the current definition of Anthothelidae .

Etymology: The new generic name is derived from the Latin, lateo (to lurk, lie hidden or escape notice) and thela in recognition that the genus has long been mistaken for specimens of Anthothela .