Big trees of small baskets: phylogeny of the Australian genus Spyridium (Rhamnaceae: Pomaderreae), focusing on biogeographic patterns and species circumscriptions
Author
Clowes, Catherine
Author
Fowler, Rachael M.
Author
Fahey, Patrick S.
Author
Kellermann, Jürgen
Author
Brown, Gillian K.
Author
Bayly, Michael J.
text
Australian Systematic Botany
2022
2022-05-18
35
2
95
119
http://dx.doi.org/10.1071/sb21034
journal article
293192
10.1071/SB21034
3342e1b6-1f21-44a4-a117-a2b6d07545f1
1446-5701
10949882
Spyridium phylicoides
,
S
.
sp. Dwarf (
J
.Kellermann 579) and
S
.
sp. Red Dots (
J
.Kellermann 689)
Spyridium phylicoides
is polyphyletic and requires taxonomic revision. In both phylogenies, samples of
S. phylicoides
were found in two clades (Clades
I
and
J
2,
Fig. 2
; Clades
M
1,
M
3 and
Q
1,
Fig. 5
). There is no biogeographic pattern to these (
Fig. 4
) and perhaps further unidentified forms exist within
S. phylicoides
, in addition to the two forms already given phrase names, namely,
S
. sp. Dwarf (
J
.Kellermann 579) Kellermann and
S
.
sp. Red Dots (
J
.Kellermann 689) Kellermann (
Table 2
).
Spyridium
sp.
Dwarf (
J
.Kellermann 579) is distinguished from
S. phylicoides
by generally smaller leaves and low-growing, almost prostrate habit (
J
. Kellermann, unpubl. data). However, the distribution of samples of
S
.
sp. Dwarf (
J
.Kellermann 579;
Fig. 5
) overlaps with that of many species found in
SA
(
Fig. 3
f
,
g
,
i
,
j
); therefore, it is possible that the incongruent result for this taxon (unresolved in the nrDNA phylogeny and polyphyletic in the cpDNA tree;
Fig. 2
,
5
) may be attributed to chloroplast capture or ILS. Only one accession of
S
.
sp. Red Dots (
J
.Kellermann 689) was included in this study and support for this taxon as distinct from
S. phylicoides
in either phylogeny is limited (Clade
J
2,
Fig. 2
; Clade
M
3,
Fig. 5
). We recommend further investigation into both phrase-name taxa, particularly
S
.
sp. Dwarf (
J
.Kellermann 579), and a more detailed investigation into the circumscription of
S. phylicoides
.