On the molecular and morphological evolution of continental and insular Cryptorchestia species, with an additional description of C. garbinii (Talitridae)

Semi-terrestrial talitrid amphipods of the genus Cryptorchestia (sensu Lowry and Fanini 2013) associated with freshwater-soaked leaf litter were known to occur in inland lakes of Turkey and at the shores of the Black Sea. Before 2013 they had been reported as Orchestia cavimana and later as Cryptorc...

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Bibliographic Details
Published in:ZooKeys
Main Authors: Domenico Davolos, Elvira De Matthaeis, Leonardo Latella, Marco Tarocco, Murat Ă–zbek, Ronald Vonk
Format: Article in Journal/Newspaper
Language:English
Published: Pensoft Publishers 2018
Subjects:
Online Access:https://doi.org/10.3897/zookeys.783.26179
https://doaj.org/article/ea4af9a5cb2b4cff9ea0eaf8f7dbd49e
Description
Summary:Semi-terrestrial talitrid amphipods of the genus Cryptorchestia (sensu Lowry and Fanini 2013) associated with freshwater-soaked leaf litter were known to occur in inland lakes of Turkey and at the shores of the Black Sea. Before 2013 they had been reported as Orchestia cavimana and later as Cryptorchestia cavimana. In our phylogenetic tree, inferred from a mitochondrial and nuclear gene dataset (cytochrome oxidase I (COI), and histone H3 (H3), respectively), we show that these Turkish populations belong to Cryptochestia garbinii, a common and widespread continental species, which is closely related to C. cavimana (endemic to Cyprus) and C. ruffoi (endemic to Rhodes). For the Turkish and European populations of C. garbinii, we found low levels of both genetic differentiation and morphological variation, and an age-related size variability (increasing at each moult) of the small lobe in the male gnathopod I merus, the main taxonomically diagnostic character for Cryptorchestia. A mainland (C. garbinii) versus insular isolation and in situ speciation (C. cavimana, and C. ruffoi) in the two east Mediterranean islands of Cyprus and Rhodes is discussed in relation to terrestrial Cryptorchestia species endemic to North East Atlantic volcanic islands (Azores, Canary Islands, and Madeira). The incorporation of five Mediterranean and Atlantic Orchestia species in the Bayesian analysis of the two genes (COI, and H3) indicated that both genera Orchestia and Cryptorchestia are not monophyletic.