Research Article |
Corresponding author: Anton M. Glushchenko ( gluschenkoam@studklg.ru ) Academic editor: Kalina Manoylov
© 2020 Anton M. Glushchenko, John Patrick Kociolek, Irina V. Kuznetsova, Maxim S. Kulikovskiy.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Glushchenko AM, Kociolek JP, Kuznetsova IV, Kulikovskiy MS (2020) Four new species from the diatom (Bacillariophyceae) genus Adlafia Moser, Lange-Bertalot & Metzeltin from waterbodies of Vietnam. PhytoKeys 162: 13-27. https://doi.org/10.3897/phytokeys.162.57657
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Four species of the diatom genus Adlafia were found from waterbodies of Vietnam and described as new to science. Their formal descriptions are presented herein and they are illustrated by light and scanning electron micrographs. These new species are: A. lamdongiensis Glushch., Kulik. & Kociolek, sp. nov., A. babeiensis Glushch., Kulik. & Kociolek, sp. nov., A. vietnamensis Glushch., Kulik. & Kociolek, sp. nov. and A. dauiensis Glushch., Kulik. & Kociolek, sp. nov. These species are then compared to other similar taxa. Our new findings add to the number of species in this interesting genus and contribute to our understanding of the unique diatom flora found in Vietnam.
Adlafia, diatoms, morphology, new species, Southeast Asia, Vietnam
The genus Adlafia was proposed by Moser et al. (
The genus includes 27 species and infraspecific taxa (
Southeast Asia is a floristically interesting region, from which many new genera and species of centric and pennate diatoms have been described recently (see
The aim of our work was to identify the species diversity of the genus Adlafia in freshwater ecosystems of Vietnam.
A list of all samples examined in this study with their geographic positions is presented in Table
List of samples examined in this study. Geographic locality of samples and measured parameters indicated.
Sample/Slide | Locality | Habitat | Coordinates | Altitude, m | Temperature, °C | pH | Conductivity, µS cm-1 | Coll. date |
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00269 | Lâm Đồng Province, Da Tien Reservoir | benthos | 11°58.816'N, 108°26.987'E | 1503 | 21.5 | 6.4 | 81 | 21.06.2012 |
00321 | Khánh Hòa Province, Hòn Bà Nature Reserve, Dầu River | wet moss | 12°06.768'N, 108°59.888'E | 275 | 24 | 6.7 | 92 | 28.05.2012 |
00325 | Khánh Hòa Province, Suối Tiên River | benthos and periphyton | 12°12.199'N, 109°01.694'E | 68 | 26 | 6.9 | 101 | 02.07.2012 |
02168 | Bắc Kạn Province, Ba Bể Lake | benthos | 22°23.605'N, 105°36.856'E | 163 | 26 | 8.5 | 174 | 19.04.2015 |
03593 | Khánh Hòa Province, Khe River | periphyton | 12°16.735'N, 108°54.677'E | 34 | 26.8 | 6.9 | 84 | 08.07.2010 |
04633 | Khánh Hòa Province, Hồ Câu Đôi Reservoir | periphyton | 12°15.750'N, 109°04.012'E | 9 | 29 | 6.8 | 110 | 14.09.2010 |
Division: Bacillariophyta Haeckel
Class: Bacillariophyceae Haeckel
Naviculaceae incertae sedis
Slide no. 00269 in collection of Maxim Kulikovskiy at the Herbarium of the Institute of Plant Physiology Russian Academy of Science, Moscow, Russia, represented here by Fig.
Vietnam. Lâm Đồng Province, Da Tien Reservoir, benthos, 11°58.816'N, 108°26.987'E, 1503 m elev., leg. E.S. Gusev, 21.06.2012.
LM (Fig.
SEM, external view (Fig.
SEM, internal view (Fig.
Epithet refers to the province of Vietnam (Lâm Đồng Province) where the specimens were found.
Vietnam. Type locality (slide no. 00269) and slide no. 03593.
Slide no. 02168 in collection of Maxim Kulikovskiy at the Herbarium of the Institute of Plant Physiology Russian Academy of Science, Moscow, Russia, represented here by Fig.
Vietnam. Bắc Kạn Province, Ba Bể Lake, benthos, 22°23.605'N, 105°36.856'E, 163 m elev., leg. E.S. Gusev, 29.04.2015.
LM (Fig.
SEM, external view (Fig.
SEM, internal view (Fig.
Epithet refers to the lake of Vietnam where the new species was found.
Vietnam. Known only from the type locality.
Slide no. 00325 in collection of Maxim Kulikovskiy at the Herbarium of the Institute of Plant Physiology Russian Academy of Science, Moscow, Russia, represented here by Fig.
Vietnam. Khánh Hòa Province, Suối Tiên River, benthos and periphyton, 12°12.199'N, 109°01.694'E, 68 m elev., leg. E.S. Gusev, 02.07.2012.
LM (Fig.
SEM, external view (Fig.
SEM, internal view (Fig.
Epithet refers to the country where the new species was found.
Vietnam. Slides no. 00325 (type locality) and no. 04633.
Slide no. 00321 in collection of Maxim Kulikovskiy at the Herbarium of the Institute of Plant Physiology Russian Academy of Science, Moscow, Russia, represented here by Fig.
Vietnam. Khánh Hòa Province, Hòn Bà Nature Reserve, Dầu River, wet moss, 12°06.768'N, 108°59.888'E, 275 m elev., leg. E.S. Gusev, 2.07.2012.
LM (Fig.
SEM, external view (Fig.
SEM, internal view (Fig.
Epithet refers to the river of Vietnam where the new species was found.
Vietnam. Known only from the type locality.
The four new species described here from Southeast Asia are morphologically similar to each other, but can be differentiated on the basis of valve shape, valve ends and striae density. All species share the morphological features typical for the genus Adlafia. A comparison of species to each other and with previously-described taxa shows that the new species from Southeast Asia are easily distinguished, unique taxa (Table
Adlafia lamdongiensis sp. nov. resembles specimens identified by Lee as Kobayasiella venezuelensis Metzeltin & Lange-Bertalot (2007, p. 155, pl. 141, figs 10–23) specimens as illustrated with light micrographs (
Morphometric features of new Adlafia species and comparison with similar taxa.
Taxon | Outline | Valve ends | Valve length, μm | Valve width, μm | Striae in 10 μm | Areolae in 10 μm | References |
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A. lamdongiensis sp. nov. | linear with weakly convex margins | distinctly narrowly-rostrate | 9.7–13.0 | 2.5–2.8 | 45–50 | 40–50 | This study |
A. babeiensis sp. nov. | lanceolate | rostrate | 11.5–14.0 | 4.0–4.5 | 36–40 | 65–70 | This study |
A. vietnamensis sp. nov. | linear-elliptical | capitate to subcapitate | 15–22 | 3.5–5.0 | 32–34 | 50–55 | This study |
A. dauiensis sp. nov. | linear to linear-elliptical | subcapitate | 19.0–26.5 | 4.5–5.5 | 32–34 | 55–60 | This study |
Adlafia multnomahii Morales & Le | lanceolate | capitate to rostrate | 9–16 | 4–5 | 37–45 | 65–70* |
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A. detenta Heudre, Wetzel & Ector in Ector et al. | elliptic to linear-elliptic | capitate | 15–18 | 4.5–6.0 | 28–33 | 30–35 |
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A. neoniana Cantonati in Ciugulea et al. | elliptic-lanceolate | rostrate to subcapitate | 9.4–18.5 | 3.7–5.1 | 30–32 | 45–50 |
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A. decora Tusset, Tremarin & Ludwig | linear-lanceolate | rostrate | 18.2–26.2 | 4.6–5.7 | 24–32 | 50–54 |
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Kobayasiella venezuelensis Metzeltin & Lange-Bertalot sensu Lee | Linear with weakly convex margins* | subcapitate* | 12.7–13.8* | 2.7–2.8* | no data | no data |
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Adlafia babeiensis sp. nov. resembles Adlafia multnomahii Morales & Le (2005, p. 151, figs 1–38), differing from it mainly by having valves that are more lanceolate in shape and rostrate valve ends (Table
Adlafia vietnamensis sp. nov. resembles Adlafia neoniana Cantonati in
Adlafia dauiensis sp. nov. resembles Adlafia decora Tusset, Tremarin & Ludwig (2017, p. 261, figs 1–18), differing from it in having capitate, but not rostrate ends, as well as having less convex valves, with a slightly higher striae density (32–34 in 10 μm in our material in comparison with 24–32 to 10 μm in A. decora). The areola density is also different between the two species (50–54 at 10 μm in A. decora versus 55–60 at 10 μm in A. dauiensis sp. nov.) (Table
These new species were found in different water ecosystems of Vietnam that show this genus is widespread in this country, especially in acidic ecosystems.
Authors are grateful to the staff of the Centre of Electron Microscopy of the Papanin’s Institute for Biology of Inland Waters, RAS, for technical assistance. Samples were collected during expeditions organized and permitted by the Joint Russian-Vietnam Tropical Centre, Ecolan 3.2 theme. Publication is based on research carried out with financial support by Russian Science Foundation (19–14–00320) for LM, SEM, sample investigation and by framework of the state assignment (theme AAAA–A19–119041190086–6) for finishing the manuscript.