THE UNIVERSITY OF HULL Taxonomic, systematic, morphological and biological studies on Palaemon Weber, 1795 (Crustacea: Decapoda: Palaemonidae) being a Thesis submitted for the Degree of PhD in Biological Sciences in the University of Hull by Christopher William Ashelby BSc (Hons) (University of Plymouth) December 2012 Contents Acknowledgements ........................................................................................................ i General Abstract............................................................................................................. v General Introduction ...................................................................................................... 1 Chapter 1: Taxonomy of Palaemon ............................................................................. 19 A new species of Palaemon (Crustacea, Decapoda, Palaemonidae) from West Africa, with a re-description of Palaemon maculatus (Thallwitz, 1892) [Published in: Zootaxa 2085: 27-44 (2009)] ........................................................................... 21 Palaemon vicinus sp. nov. (Crustacea: Decapoda: Palaemonidae), a new species of caridean shrimp from the tropical eastern Atlantic. [Published in: Zoologische Mededelingen Leiden 83(27): 825-839 (2009)] ................................................... 51 A new genus of palaemonid shrimp (Crustacea: Decapoda: Palaemonidae) to accommodate Leander belindae Kemp, 1925, with a redescription of the species. [Published in: De Grave, S. & Fransen, C.H.J.M. (eds.). 2010. Contributions to shrimp taxonomy. Zootaxa 2372: 1–414] ............................................................ 73 Marine and estuarine shrimp fauna of Taiwan (Crustacea: Decapoda): Subfamily Palaemoninae. [In press: Chan, T.-Y. (ed) Crustacean fauna of Taiwan: Shallow water shrimps, Volume I — Caridea, Dendrobranchiata, Stenopodidea. Keelung, Taiwan: National Taiwan Ocean University] ....................................................... 89 Chapter 2: Systematics of Palaemon ......................................................................... 143 Regional scale speciation reveals multiple invasions of freshwater in Palaemoninae (Decapoda). [Published in: Zoologica Scripta 41(3): 293–306 (2012)] ................................................................................................................. 143 Chapter 3: Morphometrics of Palaemon .................................................................... 173 A geometric morphometric analysis of two reported morphological forms of Palaemon longirostris along European Atlantic coasts. ..................................... 173 Chapter 4: Functional morphology of Palaemon ....................................................... 199 Preliminary observations on the mandibles of Palaemonoid shrimp (Crustacea: Decapoda: Caridea). ............................................................................................ 199 Chapter 5: Human-mediated spread of Palaemon ..................................................... 237 The global invader Palaemon macrodactylus (Decapoda, Palaemonidae): an interrogation of records and a synthesis of data. [Published in: Crustaceana 86(5): 594-624] .............................................................................................................. 239 C. Ashelby – Aspects of the biology of Palaemon Diet analysis indicates seasonal fluctuation in trophic overlap and separation between a native and an introduced shrimp species (Decapoda: Palaemonidae) in the Tidal River Thames. ..................................................................................... 289 General Discussion .................................................................................................... 317 C. Ashelby – Aspects of the biology of Palaemon for my wife and children C. Ashelby – Aspects of the biology of Palaemon C. Ashelby – Aspects of the biology of Palaemon Acknoweldgements Acknowledgements This section of the thesis is perhaps the most difficult section to write as gratitude can not be justified by citing endless references or applying any statistical tests. Despite this I am well aware that this is likely to be the most read part of the thesis and many people will probably get no further through the thesis. For any people I have omitted, I am truly sorry; this is not a reflection on you or the value of your contributions. Likewise, the order in which people are acknowledged does not reflect the value of their contribution; all contributions have been equally valuable and all have helped me get to this point. Unicomarine (and subsequently Thomson Unicomarine) are thanked for financial support, providing time and resources to enable the completion of these studies. All my work colleagues, both past and present, are thanked for advice, friendship, help and shouldering the extra burden of work to allow me to concentrate on my studies. Most of all they are thanked for tolerating my shrimp obsession and the occasional stench of years-old, sometimes poorly preserved pots of shrimps. Unfortunately for them, whilst the thesis is complete, the obsession continues. Special thanks are due to Tim, Lydia and Charlotte who have borne the brunt of this responsibility. Lisa Conyers, Laura Goulding, Kate Pocklington and Louisa Wood are thanked for their help and conversation during various visits to OUMNH. Dirk Platvoet (ZMA) is thanked for his hospitality during a visit to the ZMA and for providing one of the best pieces of advice I have received. Miranda Lowe and Paul Clark (NHM) are thanked for allowing me access to their collection and for support during visits to their museum. Fiona Ware (NMS), Karen van Dorp and Jacques Smit (Naturalis), Regis Cleva (MNHN), Stephen Keable (AM), Gavin Dally (NTM), Tin- Yam Chan (NTOU), Karen Reed (USNM), Eduardo Spivak, Christoph Lejeusne, Melanie Béguer and Michel Girardin amongst others have provided valuable specimens for study. Charles Fransen (Naturalis) is also acknowledged for providing specimens, advice, information and insightful conversations. Thanks to my fellow students at the STRI Training in Tropical Taxonomy: Short Course in Shrimp Taxonomy (Caridea, Dendrobranchiata and Stenopodidea), C. Ashelby – Aspects of the biology of Palaemon i Acknowledgements Betel Martínez-Guerrero, Juan Felipe Lazarus-Agudelo, Jure Jugovic, Laura Anderson, Nuno Simões, Leslie Harris, Carolina Tavares, Patricio Hernáez, Javier Luque, Nicola Dobson, Lucas Torati and Tim Page; I learned from you all. In particular Rachel Collin secured the funding and helped with the organisation of this course. Tim Page is thanked for his patience, advice, help, being the only person able to explain genetic theory to me such that I now have some understanding and for showing me how presentations can and should look. Cédric d’Udekem d’Acoz and Arthur Anker are gratefully acknowledged for numerous stimulating conversations, supplying difficult to obtain literature, friendship and advice. To my supervisors Magnus Johnson (University of Hull) and Sammy De Grave (Oxford University Museum of Natural History) I owe a huge debt of gratitude. Their continuing advice, patience, guidance, support, encouragement and, above all, friendship has made this study a possibility. Their own passion for the subject has been a huge motivational force. Above all else, the support and love of my family, both during the completion of these studies and elsewhere in my life, has been vital to the realisation of this work. To my parents, thank you for your love, encouragement, advice and the sacrifices made throughout my life and for believing in me. Thanks are also due to my brother and sisters who have similarly provided love and support. To my children, Adam and Alice, thank you for making me smile and laugh and for understanding why I haven’t always been able to play. Finally, without the love and support of my wife, Catherine, this study simply wouldn’t have been possible. Throughout the many ups and downs of this work she has stood beside me and encouraged me. Many days, evenings and weekends she has become a ‘shrimp-widow’ as I have buried my head in the books or locked myself away with a microscope and some shrimps, yet she has never once complained or protested. One day I hope I can reciprocate but until such time I can only express my heartfelt thanks. ii C. Ashelby – Aspects of the biology of Palaemon Abstract C. Ashelby – Aspects of the biology of Palaemon iii Abstract iv C. Ashelby – Aspects of the biology of Palaemon Abstract General Abstract Palaemon is a large genus of marine, brackish and freshwater shrimps and are amongst the most familiar shrimps to scientists and amateur naturalists. Despite being familiar and widely reported they remain understudied. A series of studies was conceived to address some of the outstanding questions on the taxonomy, systematics, functional morphology and invasive biology of Palaemon and related genera. As previous studies have revealed that there is a lack of stable morphological characters to define both species and the genus Palaemon itself traditional taxonomic studies were conducted to highlight the potential of novel characters to delineate species and genera within the subfamily Palaemoninae. Previous phylogenetic work, both morphological and molecular, has also suggested that the genus probably does not represent a monophyletic lineage. The previous molecular phylogenetic studies were expanded on to give a phylogeny of the subfamily Palaemoninae based on the genes