DOI: 10.5061/dryad.1vt02
title: Data from: Surviving in mountain climate refugia: new insights from the genetic diversity and structure of the relict shrub Myrtus nivellei (Myrtaceae) in the Sahara desert

description: The identification of past glacial refugia has become a key topic for
 conservation under environmental change, since they contribute importantly
 to shaping current patterns of biodiversity. However, little attention has
 been paid so far to interglacial refugia despite their key role for the
 survival of relict species currently occurring in climate refugia. Here,
 we focus on the genetic consequences of range contraction on the relict
 populations of the evergreen shrub Myrtus nivellei, endemic in the Saharan
 mountains since at least the end of the last Green Sahara period, around
 5.5 ka B.P. Multilocus genotypes (nuclear microsatellites and AFLP) were
 obtained from 215 individuals collected from 23 wadis (temporary rivers)
 in the three main mountain ranges in southern Algeria (the Hoggar, Tassili
 n’Ajjer and Tassili n’Immidir ranges). Identical genotypes were found in
 several plants growing far apart within the same wadis, a pattern taken as
 evidence of clonality. Multivariate analyses and Bayesian clustering
 revealed that genetic diversity was mainly structured among the mountain
 ranges, while low isolation by distance was observed within each mountain
 range. The range contraction induced by the last episode of aridification
 has likely increased the genetic isolation of the populations of M.
 nivellei, without greatly affecting the genetic diversity of the species
 as a whole. The pattern of genetic diversity observed here suggests that
 high connectivity may have prevailed during humid periods, which is
 consistent with recent paleoenvironmental reconstructions.
description: Migliore et al - AFLP
 Myrtus nivelleiAFLP (Amplified fragment
 Length Polymorphism) dataset examined for 215 individuals of Myrtus
 nivellei (Myrtaceae) sampled within 23 wadis in the central Saharan
 mountains, and listed per row. Each individual is denoted by a four-letter
 code: one letter for the country (A for Algeria), two letters for the
 mountain range (TA for Tassili n’Ajjer, HO for Hoggar and IM for Immidir),
 and one letter for the wadi sampled, with a supplementary letter for
 individuals sampled within the Tarit wadi (AIMT) more intensively
 analyzed.Three combinations of primers have been selected: EcoRI-AAGG with
 MseI-CCAG, EcoRI-AAC with MseI-CAC, EcoRI-AAC with MseI-CAA. AFLP
 multilocus profiles were transcribed in a matrix summarizing the presence
 (1) or the absence (0) of AFLP markers (123 markers retained and presented
 in column).Migliore et al - SSR
 Myrtus nivelleiSSR (simple sequence
 repeats) dataset examined for 215 individuals of Myrtus nivellei
 (Myrtaceae) sampled within 23 wadis in the central Saharan mountains, and
 listed per row. Each individual is denoted by a four-letter code: one
 letter for the country (A for Algeria), two letters for the mountain range
 (TA for Tassili n’Ajjer, HO for Hoggar and IM for Immidir), and one letter
 for the wadi sampled, with a supplementary letter for individuals sampled
 within the Tarit wadi (AIMT) more intensively analyzed. Eleven nuclear
 microsatellite markers (Myrcom1 to Myrcom11) developed for Myrtus communis
 by Albaladejo et al. 2010 (see reference [48] in the article) were used in
 this study; only the seven polymorphic loci were presented
 here.