<p><strong>An updated species inventory of<em> Callithamnion</em> <em>sensu lato</em> Rhodophyta, Callithamniaceae in South Africa with the description of <em>Callithamnion africanum sp</em>. <em>nov</em>.</strong></p>

Abstract

The species diversity of Callithamnion sensu lato in South Africa is re-visited using existing literature, morphology and DNA. The identity of a putative new species is confirmed as distinct using DNA and is described here as Callithamnion africanum sp. nov. Callithamnion africanum differs molecularly and morphologically from a similar species, C. cordatum with which it shares a similar habitat and distribution range in South Africa. Callithamnion africanum is resolved in the Callithamnion sensu stricto clade and is sister to the type species of the genus, Callithamnion corymbosum. Additionally, Callithamnion stuposum, a species described from South Africa and a common component of the seaweed flora, was recovered in the larger, unresolved Callithamnion sensu lato clade. An updated species inventory of Callithamnion sensu lato in South Africa is provided, and indicates a lack of sequence data for the large majority of species. Furthermore, a global rbcL phylogeny highlights a number of taxonomic concerns regarding the classification of taxa circumscribed to Callithamnion sensu lato and calls for a global revision using DNA, type specimens or material collected from near type localities.

A taxonomically informed DNA reference library to facilitate future biodiversity assessments and monitoring: a case study using seaweeds along a tropical-temperate transition zone in South Africa

“…Our results support the hypothesis that Port Alfred can act as a surrogate of the seaweed diversity for the AMP. Preliminary phylogenetic analyses and comparison with the literature suggest that our dataset contained two potentially new genera (1 previously identified-‘ Tenebris’ sensu Johnson 2017), 19 unidentified and potentially new species, one new species (Reddy et al . 2020b), one reinstated species (Reddy et al .…”

“…The long and often complicated process of alpha taxonomy and a lack of expertise on certain groups of marine organisms such as seaweeds (De Clerck et al 2013) 2006), it is certainly useful for understanding the overall biodiversity of a region and can be used to guide further research efforts (Reddy et al 2020b;Reddy et al 2023). The need for taxonomically guided DNA reference libraries however is much needed and is becoming more pertinent than ever, especially in an age of metabarcoding or eDNA (Cristescu and Hebert, 2018).…”

“…2021). While DNA barcoding is no substitute for alpha taxonomy (DeSalle 2006), it is certainly useful for understanding the overall biodiversity of a region and can be used to guide further research efforts (Reddy et al . 2020b; Reddy et al .…”

“…Callithamnion collabens was previously recorded along the BMP and AMP. However, specimens along the AMP were shown to be a new species (Reddy et al . 2020b), thereby restricting the distribution range of C. collabens to the BMP.…”