Rewriting the evolutionary history of the lichen genus Sticta ( Ascomycota : Peltigeraceae subfam. Lobarioideae ) in the Hawaiian islands
Hawaiian lichen species have been thought to be widespread, with low endemism. Nine species of the genus Sticta ( Peltigeraceae subfamily Lobarioideae ) have previously been reported for Hawaii, all supposedly cosmopolitan or Pantropical or widespread in the Paleotropics except for the putative...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
W. Szafer Institute of Botany, Polish Academy of Sciences
2020-06-01
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| Series: | Plant and Fungal Systematics |
| Subjects: | |
| Online Access: | https://pfsyst.botany.pl/Rewriting-the-evolutionary-history-of-the-lichen-genus-Sticta-Ascomycota-Peltigeraceae,120423,0,2.html |
| Summary: | Hawaiian lichen species have been thought to be widespread, with low endemism.
Nine species of the genus Sticta ( Peltigeraceae subfamily Lobarioideae ) have previously
been reported for Hawaii, all supposedly cosmopolitan or Pantropical or widespread in
the Paleotropics except for the putative endemic S. plumbicolor . This study is the first one
employing a molecular phylogenetic approach to Hawaiian Sticta , elucidating the relationships
of these conspicuous and ecologically important macrolichens. We sequenced the ITS
fungal barcoding locus and used a maximum likelihood approach to reconstruct phylogenetic
relationships of Hawaiian Sticta from a large dataset of more than 200 species. Thirteen
species were identified among Hawaiian Sticta , four more than previously recorded. Of
these, seven are new to science and putatively endemic to Hawaii. Only four previously
reported species were confirmed: S. fuliginosa , S. limbata , S. plumbicolor and S. tomentosa .
Together with S. plumbicolor and S. scabrosa subsp. hawaiiensis (described elsewhere),
putative endemism in Hawaiian Sticta is estimated at 69%. The 13 species correspond
to nine or ten colonization events, predominantly from the Australasian realm. Thus, the
evolutionary history of Sticta lichens in the Hawaiian archipelago is very different from
what has been assumed, and matches that of other organisms in many aspects. The seven
new species, all with cyanobacterial photobionts, are Sticta acyphellata , a small, stipitate
Sticta with isidia and lacking cyphellae; S. antoniana , a mid-sized Sticta with abundant
marginal lobules, apothecia, and a thick, grey-brown lower tomentum ending abruptly to
leave a bare marginal zone; S. emmanueliana , a small, shortly stipitate Sticta forming small
lobes with marginal isidia and black cilia; S. flynnii , a small, shortly stipitate Sticta with
largely unbranched thallus with marginal isidia and a veined underside producing large,
irregular cyphellae; S. hawaiiensis , a small Sticta with a suborbicular thallus with laminal
isidia, conspicuous white cilia, and papillae on the membrane of the cyphellae; S. smithii ,
a small, stipitate Sticta with marginal, flattened isidia and small cyphellae; and S. waikamoi ,
a small to mid-sized Sticta with a much-branched thallus with slightly canaliculate
lobes and marginal, dark isidia, and a thick, dark brown lower tomentum with strongly
contrasting whitish cyphellae. |
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| ISSN: | 2544-7459 2657-5000 |