Biodiversity of dogfishes (genus SQUALUS) in the eastern Atlantic and Mediterranean Sea – a molecular perspective A. VERÍSSIMO, D. ZAERA-PEREZ, R. LESLIE, S. IGLÉSIAS, B. SÉRET, P. GRIGORIOU, C. GUBILI, J. NAVARRO, C. DUFFY, A.M. GRIFFITHS European Elasmobranch Association Meeting 9-11 October 2015, Peniche, Portugal

The Genus Squalus - Dogfishes 27 species currently accepted Mostly coastal demersal sharks Worldwide distribution <1,5 m total length Yolk-sac viviparous Active swimmers

SQUALUS – ALPHA TAXONOMY Many inconsistencies/difficulties in species identification Poor/ambiguous species descriptions High morphological similarity among species Species diversity still not fully described Twelve new species described from the Indo- Pacific (Last et al. 2007; White & Iglesias 2011) Many new species previously undetected, other nominal species recently resurrected (Last et al. 2007; Ebert et al. 2010)

SQUALUS – ATLANTIC OCEAN sensu lato Five species currently recognized S. acanthias (VU) S. blainville (DD) S. cubensis (DD) S. megalops (DD) S. mitsukurii (DD) Taxonomic issues Difficulties in species identification S. mitsukurii may be a species complex

OBJECTIVES Re-evaluate species-level diversity of Squalus in the eastern Atlantic & Mediterranean Molecular markers (mtDNA COI, 551 bp) Morphology (meristics & morphometrics) Biology (life history traits)

SAMPLING Specimens sampled de novo along the eastern Atlantic & Mediterranean DNA sequences (N=128) Whole specimens as vouchers Additional COI sequences from GenBank and BOLD.org (N=288) - Worldwide distribution - Multiple Squalus species 19 Squaus species represented (out of 27)

“megalops-cubensis” - group SQUALUS - COI data “acanthias” - group 100% 100% “megalops-cubensis” - group 97% “blainville” - group

CLADE 1: “acanthias” group Atlantic, Mediterranean, S. Pacific 100% N. Pacific N. Pacific © Monterey Bay Aquarium

CLADE 2: “megalops – cubensis” group 96% Gulf of Mexico Australia 89% 100% Kermadec Islands, New Zealand Mediterranean, Portugal – South Africa Portugal 86% Japan & Taiwan Mediterranean, Portugal – South Africa © Museu História Natural e Ciência

Zooming into the megalops-like subgroup Atlantic and Mediterranean megalops-like may be considered a separate species, with widespread distribution in the Mediterranean and eastern Atlantic. White starts show locations with “megalops”-like specimens sampled in this study. Map shows currently accepted distribution of S. megalops.

CLADE 3: “blainville” group 100% Australia Uruguay & South Africa Indonesia & Australia 97% 95% Australia Gulf of Mexico Uruguay, Gulf of Mexico, Guine-Conakri/Bissau 99% Tunisia & Gabon Indonesia & Australia Indonesia 94% Australia 89% Taiwan 86% 90% Australia New Zealand 87% Indonesia & Australia 89% 87% Hawaii Taiwan

Squalus blainville CLADE 3: Squalus blainville type 100% 97% 95% 99% Is this the “true” S. blainville?? Type locality is Nice, France. Most specimens identified as S. blainville clustered into the “megalops” group. Tunisia & Gabon 94% According to Muñoz-Chaplli & Ramos (1989), Risso’s description of A. [S.] blainville agrees well with several species in the genus… For nomenclatural stability, the long-snouted Squalus of the Mediterranean was kept as S. blainville. 89% 86% 90% 87% 89% 87%

The megalops vs. blainville issue Biological Data Risso 1826 is the original description of S. blainville. According to Muñoz-Chapulli & Ramos, Risso’s description can fit in with several species in the genus… For the sake of nomenclatural stability, have proposed to keep the taxon name to designate long-snouted Squalus from the Mediterranean and eastern Atlantic. ??

The megalops vs. blainville issue Several diagnostic characters have been proposed by previous studies, but this has not clarified the ambiguity in species identification and the issue of inconsistency species identification has been perpetuated.

What about S. mitsukurii? 100% Australia Uruguay & South Africa 97% 95% Gulf of Mexico Uruguay, Gulf of Mexico, Guine-Conakri/Bissau 99% 94% 89% 86% 90% 87% 89% 87% Hawaii

Zooming into the mitsukurii-like specimens Atlantic “mitsukurii” are genetically distinct from Hawaiian specimens, and likely form distinct species. Unresolved status among Atlantic “mitsukurii”. Type locality of S. mitsukurii Jordan & Snyder 1903 is Japan. The Hawaiian “mitsukurii” may or may no be the “true” mitsukurii, but the Atlantic “mitsukurii” appear as very distinct lineage(s).

Presence of cryptic diversity in the Eastern Atlantic! Summary Inconsistent use of the taxon names S. blainville and S. megalops in the Mediterranean and Eastern Atlantic. Atlantic & Mediterranean megalops-like specimens may be a distinct species from the Australian megalops. Very distinct Atlantic vs. Pacific lineages currently designated under the taxon name S. mitsukurii. Presence of cryptic diversity in the Eastern Atlantic!

Acknowledgements To those that have contributed with samples and/or data Funding agencies