morphological variation
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Forests ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 112
Azadeh Rezapour ◽  
Marika Truu ◽  
Martin Maddison ◽  
Gristin Rohula-Okunev ◽  
Arvo Tullus ◽  

Peatland drainage based on ditch systems is a widely used forestry management practice in the boreal and hemiboreal forests to improve tree growth. This study investigated the morphological variation in absorptive roots (first- and second-order roots) across the distance gradient from the ditch with four sampling plots (5, 15, 40, and 80 m) in six drained peatland forests dominated by Downy birch and Norway spruce. The dominating tree species had a significant effect on the variation in absorptive root morphological traits. The absorptive roots of birch were thinner with a higher specific root area and length (SRA and SRL), higher branching intensity (BI), and lower root tissue density (RTD) than spruce. The distance from the ditch affected the absorptive root morphological traits (especially SRA and RTD), but this effect was not dependent on tree species and was directionally consistent between birch and spruce. With increased distance from the ditch (from plot 5 to plot 80), the mean SRA increased by about 10% in birch and 5% in spruce; by contrast, the mean RTD decreased by about 10% in both tree species, indicating a potential shift in nutrient foraging. However, soil physical and chemical properties were not dependent on the distance from the ditch. We found a species-specific response in absorptive root morphological traits to soil properties such as peat depth, pH, and temperature. Our results should be considered when evaluating the importance of morphological changes in absorptive roots when trees acclimate to a changing climate.

2022 ◽  
pp. 119-132
Deborah Vicari ◽  
Richard C. Sabin ◽  
Richard P. Brown ◽  
Olivier Lambert ◽  
Giovanni Bianucci ◽  

The false killer whale (Pseudorca crassidens (Owen, 1846)) is a globally distributed delphinid that shows geographical differentiation in its skull morphology. We explored cranial morphological variation in a sample of 85 skulls belonging to a mixed sex population stranded in the Moray Firth, Scotland, in 1927. A three-dimensional digitizer (Microscribe 2GX) was used to record 37 anatomical landmarks on the cranium and 25 on the mandible to investigate size and shape variation and to explore sexual dimorphism using geometric morphometric. Males showed greater overall skull size than females, whereas no sexual dimorphism could be identified in cranial and mandibular shape. Allometric skull changes occurred in parallel for both males and females, supporting the lack of sexual shape dimorphism for this particular sample. Also, fluctuating asymmetry did not differ between crania of males and females. This study confirms the absence of sexual shape dimorphism and the presence of a sexual size dimorphism in this false killer whale population.

2022 ◽  
Vol 6 (1) ◽  
José V Pérez Santa-Rita ◽  
John W Brown ◽  
Joaquín Baixeras

Abstract This is the first morphological study of the male hindwing costal roll (CR), a scent organ of tortricid moths of the subtribe Cochylina (Lepidoptera, Tortricidae). This composite organ varies from a simple membranous roll of the hindwing costa to a complex roll that incorporates a hairpencil and two types of microscales. All the components show taxon-dependent traits. Both optical and electron microscopy are used to elucidate the structure. The costal roll is associated primarily with the Aethes Billberg, Saphenista Walsingham, Phalonidia Le Marchand, and Cochylis Treitschke groups of genera. The general notions that wing male scent organs are phylogenetically labile and that they may have arisen among closely related species as a consequence of habitat sharing are explored using network analysis and phylogenetic signal. Taxa with a costal roll certainly support a more complex area of the food web, however, the character shows a strong phylogenetic signal and is not the result of a sporadic evolution.

2022 ◽  
Vol 951 (1) ◽  
pp. 012091
R Andini ◽  
V Melinda ◽  
E Pardede ◽  
L A Yanti ◽  
Khaing Hmon ◽  

Abstract The genus Pinus is classified as one of the most widely distributed genera of conifer trees, that are majorly distributed in the Northern and Southern hemispheres. Pinus merkusii is the only member of the genus Pinus that is adapted in the tropics and grows naturally in south Equator. Its natural distribution found through-out Southeast Asia, e.g. in Indonesia; particularly on Sumatran Island. Three native strains are known on Sumatra: Aceh, Kerinci, and Tapanuli; with the first one is known as the largest population among the three and grows naturally on the high altitudes. The wood has been utilized in building construction, while the resin collected is classified as one of the most valuable Non Timber Forest Products (NTFP) worth up to US $ 50 million/year and applied in many industries. Planting of citron grass (Cymbopogon sp.) has been ’booming’ over the past seven years in the middle regions of Aceh due to its attractive selling price. As consequences, many Pinus trees have been logged and demanded as fire woods in the distillation process of citron grass. Thus, the citron grass’ plantation has been directly threatening the existence of Pinus forests. Therefore, in-situ conservation effort should be started from now on. Here, we would like to report the morphological variation (N= 15 traits) of natural Pinus (e.g., plant height, diameter of main stem, number of crowns per branch, etc.). The morphological data collected were then analysed with the Principal Component Analyses (PCA), in order to cluster the major agronomical parameters among them. This morphological data would be complemented and benefitted the efforts in the genetic study of Aceh Pinus.

2022 ◽  
Vol 12 (01) ◽  
pp. 1-15
Steven Philippe Son ◽  
Thomas Alexandrine ◽  
Sébastien Motreuil ◽  
Daniel Imbert ◽  
Jean-Raphaël Gros-Désormeaux

2021 ◽  
Vol 20 (2) ◽  
pp. 151-159
Ricardo Palacios-Aguilar ◽  
Rufino Santos-Bibiano ◽  
Jonathan Atwood Campbell ◽  
Elizabeth Beltrán-Sánchez

Small, secretive snakes comprise an important part of the herpetofauna of the Neotropics and yet most species are known from a handful of specimens due to their habits and relatively inaccessible localities. The Mexican endemic Rhadinella dysmica is the westernmost species of the genus and was described based on a single adult female. Herein we provide information on new specimens, including their morphological variation and hemipenial structure, expand the known geographic range for the species, and comment on the morphological similarities of the “dark-colored” species of the genus.

2021 ◽  
Vol 12 ◽  
Zuoying Wei ◽  
Zengqiang Xia ◽  
Jiangping Shu ◽  
Hui Shang ◽  
Stephen J. Maxwell ◽  

Cryptic species comprise two or more taxa that are grounded under a single name because they are more-or-less indistinguishable morphologically. These species are potentially important for detailed assessments of biodiversity, but there now appear to be many more cryptic species than previously estimated. One taxonomic group likely to contain many cryptic species is Dicranopteris, a genus of forked ferns that occurs commonly along roadsides in Asia. The genus has a complex taxonomical history, and D. linearis has been particularly challenging with many intra-specific taxa dubiously erected to accommodate morphological variation that lacks clear discontinuities. To resolve species boundaries within Dicranopteris, we applied a molecular phylogenetic approach as complementary to morphology. Specifically, we used five chloroplast gene regions (rbcL, atpB, rps4, matK, and trnL-trnF) to generate a well-resolved phylogeny based on 37 samples representing 13 taxa of Dicranopteris, spanning the major distributional area in Asia. The results showed that Dicranopteris consists of ten highly supported clades, and D. linearis is polyphyletic, suggesting cryptic diversity within the species. Further through morphological comparison, we certainly erected Dicranopteris austrosinensis Y.H. Yan & Z.Y. Wei sp. nov. and Dicranopteris baliensis Y.H. Yan & Z.Y. Wei sp. nov. as distinct species and proposed five new combinations. We also inferred that the extant diversity of the genus Dicranopteris may result from relatively recent diversification in the Miocene based on divergence time dating. Overall, our study not only provided additional insights on the Gleicheniaceae tree of life, but also served as a case of integrating molecular and morphological approaches to elucidate cryptic diversity in taxonomically difficult groups.

Check List ◽  
2021 ◽  
Vol 17 (6) ◽  
pp. 1745-1749
Ricardo Palacios Aguilar ◽  
Samuel A. Santa Cruz Padilla ◽  
Víctor H. Jiménez Arcos

We record the third known specimen of Tantilla coronadoi Hartweg, 1944 from Guerrero, Mexico. Our new record extends this species’ distribution by 90 km and to a new Mexican biogeographic province (Balsas Basin). The morphological similarity between this and the two previously known specimens supports the validity of the taxon, and otherwise points to the possible presence of an undescribed taxon on the coast of Guerrero. Additional fieldwork yielding a larger series of this and other infrequently encountered species may enable a better understanding of their distribution, natural history, ecology, and conservation.

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