Evolution of the Neckeraceae (Bryophyta): resolving the backbone phylogeny

Earlier phylogenetic studies, including species belonging to the Neckeraceae, have indicated that this pleurocarpous moss family shares a strongly supported sister group relationship with the Lembophyllaceae, but the family delimitation of the former needs adjustment. To test the monophyly of the Neckeraceae, as well as to redefine the family circumscription and to pinpoint its phylogenetic position in a larger context, a phylogenetic study based on molecular data was carried out. Sequence data were compiled, combining data from all three genomes: nuclear ITS1 and 2, plastid trnS-rps4-trnT-trnL-trnF and rpl16, and mitochondrial nad5 intron. The Neckeraceae have sometimes been divided into the two families, Neckeraceae and Thamnobryaceae, a division rejected here. Both parsimony and Bayesian analyses of molecular data revealed that the family concept of the Neckeraceae needs several further adjustments, such as the exclusion of some individual species and smaller genera as well as the inclusion of the Leptodontaceae. Within the family three well-supported clades (A, B and C) can be distinguished. Members of clade A are mainly non-Asiatic and nontropical. Most species have a weak costa and immersed capsules with reduced peristomes (mainly Neckera spp.) and the teeth at the leaf margins are usually unicellular. Clade B members are also mainly non-Asiatic. They are typically fairly robust, distinctly stipilate, having a single, at least relatively strong costa, long setae (capsules exserted), and the peristomes are well developed or only somewhat reduced. Members of clade C are essentially Asiatic and tropical. The species of this clade usually have a strong costa and a long seta, the seta often being mammillose in its upper part. The peristome types in this clade are mixed, since both reduced and unreduced types are found. Several neckeraceous genera that were recognised on a morphological basis are polyphyletic (e.g. Neckera, Homalia, Thamnobryum, Porotrichum). Ancestral state reconstructions revealed that currently used diagnostic traits, such as the leaf asymmetry and costa strength are highly homoplastic. Similarly, the reconstructions revealed that the 'reduced' sporophyte features have evolved independently in each of the three clades.Earlier phylogenetic studies, including species belonging to the Neckeraceae, have indicated that this pleurocarpous moss family shares a strongly supported sister group relationship with the Lembophyllaceae, but the family delimitation of the former needs adjustment. To test the monophyly of the Neckeraceae, as well as to redefine the family circumscription and to pinpoint its phylogenetic position in a larger context, a phylogenetic study based on molecular data was carried out. Sequence data were compiled, combining data from all three genomes: nuclear ITS1 and 2, plastid trnS-rps4-trnT-trnL-trnF and rpl16, and mitochondrial nad5 intron. The Neckeraceae have sometimes been divided into the two families, Neckeraceae and Thamnobryaceae, a division rejected here. Both parsimony and Bayesian analyses of molecular data revealed that the family concept of the Neckeraceae needs several further adjustments, such as the exclusion of some individual species and smaller genera as well as the inclusion of the Leptodontaceae. Within the family three well-supported clades (A, B and C) can be distinguished. Members of clade A are mainly non-Asiatic and nontropical. Most species have a weak costa and immersed capsules with reduced peristomes (mainly Neckera spp.) and the teeth at the leaf margins are usually unicellular. Clade B members are also mainly non-Asiatic. They are typically fairly robust, distinctly stipilate, having a single, at least relatively strong costa, long setae (capsules exserted), and the peristomes are well developed or only somewhat reduced. Members of clade C are essentially Asiatic and tropical. The species of this clade usually have a strong costa and a long seta, the seta often being mammillose in its upper part. The peristome types in this clade are mixed, since both reduced and unreduced types are found. Several neckeraceous genera that were recognised on a morphological basis are polyphyletic (e.g. Neckera, Homalia, Thamnobryum, Porotrichum). Ancestral state reconstructions revealed that currently used diagnostic traits, such as the leaf asymmetry and costa strength are highly homoplastic. Similarly, the reconstructions revealed that the 'reduced' sporophyte features have evolved independently in each of the three clades.Earlier phylogenetic studies, including species belonging to the Neckeraceae, have indicated that this pleurocarpous moss family shares a strongly supported sister group relationship with the Lembophyllaceae, but the family delimitation of the former needs adjustment. To test the monophyly of the Neckeraceae, as well as to redefine the family circumscription and to pinpoint its phylogenetic position in a larger context, a phylogenetic study based on molecular data was carried out. Sequence data were compiled, combining data from all three genomes: nuclear ITS1 and 2, plastid trnS-rps4-trnT-trnL-trnF and rpl16, and mitochondrial nad5 intron. The Neckeraceae have sometimes been divided into the two families, Neckeraceae and Thamnobryaceae, a division rejected here. Both parsimony and Bayesian analyses of molecular data revealed that the family concept of the Neckeraceae needs several further adjustments, such as the exclusion of some individual species and smaller genera as well as the inclusion of the Leptodontaceae. Within the family three well-supported clades (A, B and C) can be distinguished. Members of clade A are mainly non-Asiatic and nontropical. Most species have a weak costa and immersed capsules with reduced peristomes (mainly Neckera spp.) and the teeth at the leaf margins are usually unicellular. Clade B members are also mainly non-Asiatic. They are typically fairly robust, distinctly stipilate, having a single, at least relatively strong costa, long setae (capsules exserted), and the peristomes are well developed or only somewhat reduced. Members of clade C are essentially Asiatic and tropical. The species of this clade usually have a strong costa and a long seta, the seta often being mammillose in its upper part. The peristome types in this clade are mixed, since both reduced and unreduced types are found. Several neckeraceous genera that were recognised on a morphological basis are polyphyletic (e.g. Neckera, Homalia, Thamnobryum, Porotrichum). Ancestral state reconstructions revealed that currently used diagnostic traits, such as the leaf asymmetry and costa strength are highly homoplastic. Similarly, the reconstructions revealed that the 'reduced' sporophyte features have evolved independently in each of the three clades.Peer reviewe

FEEDBACK from the NGC 7538 H II region

Interstellar matter and star formatio

FEEDBACK from the NGC 7538 H

Context. The interaction of expanding H I

Characterizing the Multiphase Origin of [CII] Emission in M101 and NGC 6946 with Velocity-resolved Spectroscopy

The [C II] fine-structure transition at 158 mu m is frequently the brightest far-infrared line in galaxies. Due to its low ionization potential, C+ can trace the ionized, atomic, and molecular phases of the ISM. We present velocity-resolved [C II] and [N II] pointed observations from SOFIA/GREAT on similar to 500 pc scales in the nearby galaxies M101 and NGC 6946 and investigate the multiphase origin of [C II] emission over a range of environments. We show that ionized gas makes a negligible contribution to the [C II] emission in these positions using [N II] observations. We spectrally decompose the [C II] emission into components associated with the molecular and atomic phases using existing CO (2-1) and H I data and show that a peak signal-to-noise ratio of 10-15 is necessary for a reliable decomposition. In general, we find that in our pointings greater than or similar to 50% of the [C II] emission arises from the atomic phase, with no strong dependence on star formation rate, metallicity, or galactocentric radius. We do find a difference between pointings in these two galaxies, where locations in NGC 6946 tend to have larger fractions of [C II] emission associated with the molecular phase than in M101. We also find a weak but consistent trend for fainter [C II] emission to exhibit a larger contribution from the atomic medium. We compute the thermal pressure of the cold neutral medium through the [C II] cooling function and find log (P-th/k) = 3.8-4.6 [K cm(-3)], a value slightly higher than similar determinations, likely because our observations are biased toward star-forming regions

The PDR structure and kinematics around the compact HII regions S235 A and S235 C with [CII], [C-13 II], [O I], and HCO+ line profiles

The aim of this work is to study structure and gas kinematics in the photodissociation regions (PDRs) around the compact H II regions S235 A and S235 C. We observe the [C II], [C-13 II], and [O I] line emission, using SOFIA/upGREAT, and complement them by data of HCO+ and CO. We use the [C-13 II] line to measure the optical depth of the [C II] emission, and find that the [C II] line profiles are influenced by self-absorption, while the [C-13 II] line remains unaffected by these effects. Hence, for dense PDRs, [C-13 II] emission is a better tracer of gas kinematics. The optical depth of the [C II] line is up to 10 in S235 A. We find an expanding motion of the [C II]-emitting layer of the PDRs into the front molecular layer in both regions. Comparison of the gas and dust columns shows that gas components visible neither in the [C II] nor in low-J CO lines may contribute to the total column across S235 A. We test whether the observed properties of the PDRs match the predictions of spherical models of expanding H II region + PDR + molecular cloud. Integrated intensities of the [C-13 II], [C II], and [O I] lines are well represented by the model, but the models do not reproduce the double-peaked [C II] line profiles due to an insufficient column density of C+. The model predicts that the [O I] line could be a more reliable tracer of gas kinematics, but the foreground self-absorbing material does not allow using it in the considered regions

Self-absorption in [C II], 12CO, and H I in RCW120.: Building up a geometrical and physical model of the region

Laboratory astrophysics and astrochemistryInterstellar matter and star formatio