Invasive species display remarkable levels of
ecophysiological plasticity, which supports colonization,
population establishment and fitness across their introduction range. The red seaweed genus Asparagopsis
comprises genetically homogeneous invasive species (A.
armata) and cryptic species complexes (A. taxiformis
sensu lato) consisting of invasive mitochondrial lineages
introduced worldwide. The photosynthetic plasticity of
Australian, Mediterranean and Hawaiian Falkenbergia
stages (i.e. the tetrasporophytic stage) of A. taxiformis
lineages 2, 3 and 4 and Mediterranean isolates of A.
armata was assessed by challenging their photosynthetic
performance at five different temperatures (12–26 C).
Our aim is to portray the photosynthetic profiles in
relation to temperature for each of the aforementioned
Asparagopsis OTUs. We additionally test the physiological response of A. taxiformislineage 2 sampled within its
invasive (Mediterranean Sea) and native range (Australia) to identify physiological features associated with
invasive strains. Based on photosynthesis optima, Asparagopsis isolates were recovered into a tropical (NL2 and
L4) and a temperate (AA, Il2 and L3) group that
presented no differences in most photosynthetic parameters at the experimental temperatures, thus indicating a
greater physiological plasticity. On the other hand, low Ic
values together with an apparent lack of sensitivity in the
photosynthetic response to changing temperatures were
revealed for the Mediterranean lineage 2, indicative of
adaptive benefits that likely support its invasive success
compared to the rest of the genus. Our results represent a
valuable resource to predict distributional shifts in some
of the lineages and to anticipate control programs for
lineage 3, potentially invasive
