Bibliographic Detail
Muangmai, N., Yamagishi, Y. Zuccarello, G.C., Chirapart, A. & Lewmanomont, A., 2014
Reference:
Muangmai, N., Yamagishi, Y. Zuccarello, G.C., Chirapart, A. & Lewmanomont, A. (2014). Transferring Gracilaria irregularis (Gracilariaceae, Rhodophyta) from Thailand to Gracilariopsis based on morphological and molecular analyses. Phycological Research 62: 29-35.
Abstract:
Gracilaria irregularis, endemic to Thailand, was originally
described from Ao Len, Trat peninsula, Thailand,
and was characterized by a short, succulent thallus
with irregular branching, verrucosa-type spermatangia
(a taxonomic criterion for Gracilaria) and the absence
of nutritive filaments (a taxonomic criterion for
Gracilariopsis). Due to the combination of characters
diagnostic of both the genera Gracilaria and Gracilariopsis,
the taxonomic status of this species is
unclear. This present study reassesses the identity of
G. irregularis based on morphological features and
the large subunit of ribulose-bisphosphate carboxylase/
oxygenase gene sequences. Newly collected samples
from the type locality and KU collection were investigated.
Our morphological re-examinations were relatively
similar to the original type description, except
that the male plants showed superficial chorda-type
spermatangia, an important characteristic recognized in
Gracilariopsis. Molecular analysis placed G. irregularis
in the Gracilariopsis clade, forming a well-supported
clade with Gracilariopsis bailiniae. Detailed morphology
and molecular phylogenetic analyses clearly showed that
G. irregularis is congruous with the generic concept of
Gracilariopsis, and consequently the new combination of
Gracilariopsis irregularis is proposed. We believe that in
the original description a heterogeneous holotype was
used. Our data also shows the problems that can occur
when collections are made of multiple plants, of similar
external morphology, to describe new species.
