Dancing with dorids: Phylogenetic systematics of discodorid nudibranchs in the genus Rostanga
Janne Torres Jarin Terrence M. Gosliner Nudibranchs
2 Discodorid biology
- Gill plume around anus - A pair of finger-like oral tentacles
Within this is the genus Rostanga
Oral tentacles
3 Rostanga Bergh 1879
- Red-orange to orange coloration - Feed on sponges - Possess caryophyllidia
4 Research Questions
1) How are species within the genus Rostanga related? 2) How do morphological characteristics vary based on evolutionary relationships? 3) How effective are these characteristics at predicting the placement of taxa in the phylogeny?
5 Methods
Morphology - Scanning Electron Microscope - Radula - Caryophyllidia - Dissecting Microscope - Reproductive system
6 Radula under SEM
7 Rostanga sp. 1 Rostanga sp. 2 Rostanga sp. 3
8 Radulae under SEM Rostanga lutenscens Rostanga sp.
9 Radulae under SEM Rostanga lutenscens Thordisa sp.
10 Radulae under SEM Rostanga lutenscens Rostanga sp.
11 Radulae under SEM Rostanga lutenscens Jorunna sp.
12 Methods
Molecular - Genes COI, 16S, H3 - Sanger Sequencing - RAxML - MrBayes
13 Rostanga sp. 1 100 Rostanga sp. 1 99 Rostanga sp. 2 99 97 Rostanga sp. 3 Rostanga elandsia 100 RAxML 85 Rostanga elandsia Rostanga sp. 51 100 Rostanga sp. pink Rostanga ghiselini 29 Rostanga byga 67 56 Rostanga pulchra 26 29 Rostanga pulchra Atagemanota cristata Rostanga muscula 98 Rostanga calumus Rostanga sp. (orange) 100 Rostanga sp. (orange) 76 40 Rostanga sp. 2 orange 100 87 Rostanga sp. Rostanga sp. (red) 81 100 Rostanga sp. (red) 55 Platydoris argo 48 58 Rostanga sp. (white)
43 Gargamella gravistella Diaulula sandiegensis 72 36 Peltodoris nobilis Rostanga sp. yellow Taringa telopia
89 Rostanga lutenscens 98 35 Rostanga sp. red 35 Rostanga lutenscens red 100 Rostanga sp. 93 Rostanga sp. 61 Rostanga phepha Rostanga sp. 2 orange 99 Rostanga sp. white 96 Rostanga sp. white 100 55 Rostanga sp. Jorunna tomentosa Jorunna funebris Discodoris cebuensis
2.0
14 RAxML
15 RAxML 3 new species
16 RAxML 3 new species Thordisa sp.
17 RAxML 3 new species Thordisa sp.
Lutescens clade
18 RAxML 3 new species Thordisa sp.
Lutescens clade
Jorunna
19 RAxML 3 new species Thordisa sp. “True”Rostanga
Lutescens clade
Jorunna
20 RAxML 3 new species Thordisa sp. “True”Rostanga
? Lutescens clade
Jorunna
21 3 new species
Thordisa sp. “True”Rostanga
?
? Lutescens clade
Jorunna
22 Conclusions
1) There is some support for a grouping of “true” Rostanga that possess elongate outer teeth with divided tips. 2) The morphological and molecular data seem to support each other in determining new species and relationships.
23 Future directions
1) Look more into reproductive systems and compare those to the phylogeny. 2) Resolve issues with CO1. 3) Increase taxon sampling across the genus especially for taxa that have never been sequenced.
24 Acknowledgements
Terry Gosliner Athena Lam Laura Zamarano Rich Mooi, Kelly Larkin, and Katherine Piatek California Academy of Sciences National Science Foundation Fellow SSI Interns
25