Vertebrata fruticulosa Kuntze 1891
Creators: name: Piñeiro-Corbeira, Cristina
name: Maggs, Christine A.
name: Rindi, Fabio
name: Bunker, Francis
name: Baldock, Lin
name: Díaz-Tapia, Pilar
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Plantae
Rhodophyta
Florideophyceae
Ceramiales
Rhodomelaceae
Vertebrata
Vertebrata fruticulosa

description: Vertebrata fruticulosa (Wulfen) Kuntze
MOLECULAR IDENTIFICATION
In total 18 rbc L sequences, 16 newly determined, are available for specimens morphologically identified as Vertebrata fruticulosa from the United Kingdom, the Atlantic Iberian Peninsula and the Mediterranean. They were resolved in the rbc L phylogeny (Fig. 2) in a fully supported clade that also included sequences of V.thuyoides (Harvey) Kuntze, V. tripinnata (Harvey) Kuntze, V. subulifera (C.Agardh) Kuntze and V. furcellata (C.Agardh) Kuntze.Within this clade, specimens assigned to V. fruticulosa formed two clades that diverged by 3-3.3% (21-24 bp) and that are labelled in Figure 2 as V. fruticulosa and V. martensiana. Two haplotypes of V. fruticulosa were 0.6% (4 bp) divergent. Specimens of the V. fruticulosa clade were only found in the Mediterranean, including the Adriatic Sea, its type locality. Vertebrata martensiana has a wider distribution including the Adriatic Sea, the Atlantic Iberian Peninsula and the United Kingdom. Two haplotypes were found in the Atlantic and a third one in the Mediterranean and they diverged by 0.3-0.4% (4-6 bp).
MORPHOLOGICAL OBSERVATIONS
Specimens that were initially identified as Vertebrata fruticulosa (Fig. 4) were predominantly erect, attached to the substratum by short prostrate axes that bear rhizoids cut off from the pericentral cells. Thalli were composed of several main axes that bear branches pseudodichotomously at wide angles (>30°) (Fig. 4A, E, I). They were 250-900 in diameter in mid-parts of the thallus. Trichoblasts were absent or scarcely developed. Axes had 8-12 pericentral cells and were corticate (Fig. 4D, H, L). Specimens of the V. fruticulosa and V. martensiana clades can be distinguished by the morphological characters indicated below.
Specimens placed in the V. fruticulosa clade had main axes of indeterminate growth that were alternately branched at regular intervals and bore alternate branches of determinate growth (Fig. 4A, B). Determinate branches, in turn, bore 2-3 orders of branches mostly every 3 segments (Fig. 4C) and were 7-9 mm in length. Axes had 11-12 pericentral cells (Fig. 4D).
The specimens in the V. martensiana clade had main axes branched at irregular intervals and bore branches of determinate growth (Fig. 4E, F, I, J). Mediterranean specimens had simple or once-branched determinate branches that were 1.5 mm in length (Fig. 4G). Axes had 8-10 pericentral cells (Fig. 4H). Atlantic specimens had determinate branches 3-5 mm in length that were simple or bore up to 2 branching orders (Fig. 4K) and axes with 8-12 pericentral cells (Fig. 4L).
description: Published as part of Piñeiro-Corbeira, Cristina, Maggs, Christine A., Rindi, Fabio, Bunker, Francis, Baldock, Lin & Díaz-Tapia, Pilar, 2020, Molecular assessment of the tribes Streblocladieae and Polysiphonieae (Rhodomelaceae, Rhodophyta) in the British Isles reveals new records and species that require taxonomic revision, pp. 55-72 in Cryptogamie, Algologie 20 (8) on page 60, DOI: 10.5252/cryptogamiealgologie2020v41a8, http://zenodo.org/record/7827761