印度-西太平洋棘花鱸屬魚類和近親之多基因親緣關係及分類研究（鱸形目：花鱸科）

Abstract

花鱸科魚類是一群分布於全球熱帶至溫帶海域的小型珊瑚礁魚類。現時，花鱸科的已知物種共有248種。儘管花鱸科的物種多樣性高且分佈廣泛，多數物種棲息於印度-西太平洋（Indo-West Pacific, IWP）熱帶海域的中光層珊瑚礁，其標本的採集難度較高，故學界對其親緣關係、物種多樣性及分類的認知仍相當有限。目前，花鱸科下的分類系統，尤其是屬級分類仍存在很大的爭議。 花鱸科裡物種多樣性最高的棘花鱸屬（Plectranthias），被學界猜測為非單系群。本研究使用過去二十多年由「Tropical Deep-Sea Benthos」計劃與其相關的台法雙邊合作，在印度-西太平洋進行的船舶調查內採集到的花鱸魚類樣本，主要目標包含：一、重建印度-西太平洋花鱸科魚類的親緣關係；二、檢驗花鱸各屬，以及過往以形態歸類的屬群是否為單系群；三、以整合性分類方法探索棘花鱸屬及其相近屬之物種多樣性；四、重新建立棘花鱸屬之分類系統。 本研究共採集17屬、83種的花鱸表型種，並獲取其四個核基因（EGR1，EGR2B，RAG1，Rhodopsin）及一個粒線體基因（COI）的序列以彙集出資料矩陣，來重建花鱸科以下的親緣關係。接著，本研究針對多基因親緣關係樹中的棘花鱸系群，另外建立粒線體COI序列矩陣以進行物種界定。多基因親緣關係樹揭示棘花鱸屬、齒花鮨屬（Odontanthias）、擬花鮨屬（Pseudanthias）及櫻鮨屬（Sacura），皆為非單系群；棘花鱸屬被證實為多系群，可分為七個演化支，分別名為系群A至G。根據物種界定的分析結果，並結合COI序列歧異度、核基因單系性、形態學、生物地理學和生態學的證據，共界定出76個棘花鱸、麗鮨屬 Lepidoperca、月花鮨屬Selenanthias及擬姬鮨屬 Tosanoides的假定種。最後，結合棘花鱸屬的親緣關係及提出的物種假說，並以選定的形態特徵來鑑別七個棘花鱸系群，本研究為「棘花鱸屬」的分類提出以下之改變：一、恢復棘花鱸屬的次同物異名 Zalanthias Jordan & Evermann、Sayonara Jordon & Seale及Pelontrus Smith，以代表棘花鱸系群A、C及F；二、為系群B及G創立新的屬；三、系群D被確認為真正的棘花鱸屬。另外，系群E則有待進一步的形態學分析以給予合適的屬名。

The Anthiadidae comprises a group of small-sized reef-associated fishes found from tropical to temperate regions worldwide, encompassing 248 currently known species. Despite its broad distribution and species richness, particularly in mesophotic reefs of the tropical Indo-West Pacific (IWP), our knowledge about their phylogenetic relationships, species diversity, and the taxonomy remains limited, primarily due to challenges in sample collections for the research. As a result, the classification, especially at generic level, remains a subject of debate. Plectranthias is the most speciose genus within Anthiadidae and has been suspected to be non-monophyletic. In this study, based on samples collected during several oceanographic expeditions in the IWP over the last two decades under the program “Tropical Deep-Sea Benthos” and through joint efforts between Taiwan and France teams, my objectives are: (1) to explore the phylogeny of the IWP anthiadids; (2) to evaluate the monophyly of the anthiadids genera, especially the Plectranthias, and morphology-based genus groups; (3) to explore the species diversity in Plectranthias and its closely related genera using an integrated approach in taxonomy; and (4) to establish a new classification for Plectranthias species. To reconstruct the phylogeny of the family, a multigene dataset with one mitochondrial and four nuclear gene sequences obtained from 83 morphospecies representing 17 genera was compiled and utilized. Additional mitochondrial COI datasets with respect to the Plectranthias clades resolved from multigene phylogenetic analysis were also compiled for the DNA-based species delimitation analyses. The inferred multigene phylogeny reveals the non-monophyly of Odontanthias, Pseudanthias, Plectranthias and Sacura. Within the “Plectranthias”, seven distinct clades (A to G) are resolved. Additionally, results from DNA -based species delimitation analyses combined with evidence from COI sequence divergence, nuclear gene monophyly, morphology, biogeography and ecology, identified 76 putative species in Plectranthias, Selenanthias, Lepidoperca and Tosanoides. Together with a robust phylogenetic framework and proposed species hypothesis, I attempt to revise the taxonomy of “Plectranthias” based on selected informative morphological diagnoses for the seven resolved Plectranthias clades. I suggest the following changes for the classification: (1) the resurrection of the junior synonyms of Plectranthias, Zalanthias Jordan & Richardson, Sayonara Jordon & Seale and Pelontrus Smith for Plectranthias clades A, C and F, respectively; (2) the establishment of new genera for Plectranthias clades B and F; (3) the restriction of Plectranthias species only to Plectranthias clade D. Further morphological evaluations are still required for Plectranthias clade E before assigning a suitable genus name.