TY - JOUR

T1 - An integrated study of the biodiversity within the Pseudechiniscus suillus-facettalis group (Heterotardigrada: Echiniscidae)

T2 - 14th International Symposium on Tardigrada - Progress in Studies on Water Bears

AU - Cesari, Michele

AU - Montanari, Martina

AU - Kristensen, Reinhardt M.

AU - Bertolani, Roberto

AU - Guidetti, Roberto

AU - Rebecchi, Lorena

PY - 2020

Y1 - 2020

N2 - Pseudechiniscus is the second most species-rich genus in Heterotardigrada and in the family Echiniscidae. However, previous studies have pointed out polyphyly and heterogeneity in this taxon. The recent erection of the genus Acanthechiniscus was another step in making Pseudechiniscus monophyletic, but species identification is still problematic. The present investigation aims at clarifying biodiversity and taxonomy of Pseudechiniscus taxa, with a special focus on species pertaining to the so-called 'suillus-facettalis group', by using an integrated approach of morphological and molecular investigations. The analysis of sequences from specimens sampled in Europe and Asia confirms the monophyly of the genus Pseudechiniscus. Inside the genus, two main evolutionary lineages are recognizable: the P. novaezeelandiae lineage and the P. suillus-facettalis group lineage. Inside the P. suillusfacettalis group, COI molecular data points out a very high variability between sampled localities, but in some cases also among specimens sampled in the same locality (up to 33.3% p-distance). The integrated approach to the study of Pseudechiniscus allows confirmation of its monophyly and highlights the relationships in the taxon, pointing to its global distribution.

AB - Pseudechiniscus is the second most species-rich genus in Heterotardigrada and in the family Echiniscidae. However, previous studies have pointed out polyphyly and heterogeneity in this taxon. The recent erection of the genus Acanthechiniscus was another step in making Pseudechiniscus monophyletic, but species identification is still problematic. The present investigation aims at clarifying biodiversity and taxonomy of Pseudechiniscus taxa, with a special focus on species pertaining to the so-called 'suillus-facettalis group', by using an integrated approach of morphological and molecular investigations. The analysis of sequences from specimens sampled in Europe and Asia confirms the monophyly of the genus Pseudechiniscus. Inside the genus, two main evolutionary lineages are recognizable: the P. novaezeelandiae lineage and the P. suillus-facettalis group lineage. Inside the P. suillusfacettalis group, COI molecular data points out a very high variability between sampled localities, but in some cases also among specimens sampled in the same locality (up to 33.3% p-distance). The integrated approach to the study of Pseudechiniscus allows confirmation of its monophyly and highlights the relationships in the taxon, pointing to its global distribution.

KW - 18S

KW - 28S

KW - cytochrome c oxidase I

KW - Pseudechiniscus facettalis

KW - scanning electron microscope

KW - Pseudechiniscus suillus

KW - Tardigrada

KW - water bears

KW - MACROBIOTIDAE HUFELANDI GROUP

KW - TARDIGRADA EUTARDIGRADA

KW - SP-NOV

KW - INTERTIDAL TARDIGRADES

KW - MOLECULAR PHYLOGENY

KW - NOMINAL TAXON

KW - GEN. NOV

KW - DIVERSITY

KW - REDESCRIPTION

KW - ECHINISCOIDEA

U2 - 10.1093/zoolinnean/zlz045

DO - 10.1093/zoolinnean/zlz045

M3 - Journal article

VL - 188

SP - 717

EP - 732

JO - Zoological Journal of the Linnean Society

JF - Zoological Journal of the Linnean Society

SN - 0024-4082

IS - 3

Y2 - 30 July 2018 through 3 August 2018

ER -