Computed Microtomography (Micro-CT) in the Anatomical Study and Identification of Solenogastres (Mollusca)

Solenogastres are vermiform marine molluscs characterised by an aculiferous mantle, a longitudinal ventral pedal groove and a terminal or subterminal pallial cavity. Their classification is based in part on the type of mantle sclerites, but identification to even the family level generally requires the study of internal anatomical characters. Taxonomically important internal characters include those related to radular structure, the type of ventrolateral glandular organs of the pharynx and the reproductive system, among others. In order to study their internal anatomical organisation, according to the classical reconstruction method, serial histological sections of specimens are made, from which the 2D internal anatomy of the specimen can be reconstructed manually. However, this is a time-consuming technique that results in destruction of the specimen. Computed microtomography or micro-CT is a non-destructive technique based on the measurement of the attenuation of X-rays as they pass through a specimen. Micro-CT is faster than histology for studying internal anatomy and it is non-destructive, meaning that specimens may be used for e.g., DNA extraction or retained as intact vouchers. In this paper, the utility of micro-CT for studying taxonomically important internal anatomical structures was assessed. Results of the 3D anatomical study of the soft parts of four specimens of three species using micro-CT are presented: Proneomenia sluiteriHubrecht, 1880, Dorymenia menchuescribanaeGarcía-Álvarez et al., 2000 and Anamenia gorgonophilaKowalevsky, 1880. Micro-CT enabled detailed study of most taxonomically important anatomical characters, precise measurements of structures, and observation of the relative position of organs from a variety of angles. However, it was not possible to observe the radula and some details of the ventral foregut organs could not be discerned. Despite these limitations, results of this study highlight micro-CT as a valuable tool to compliment histology in the study of solenogaster anatomy and in non-destructively identifying animals to the family and even genus-level.

Vegetative and Leaf Anatomical Traits for Taxonomic Delimitation of Salacia L. In Sri Lanka

Salacia comprises 200 species throughout the tropical countries. In Sri Lanka, five species of this genus S. chinensis, S. diandra, S. oblonga, S. reticulata and S. acuminatissima are recorded that are considered as the synonyms under S. diandra by Wadhwa in 1996 during the revision of genus. These species are very much similar in vegetative morphology and their flowering is irregular and rare. Due to these reasons, their proper identification and determination are difficult and identification of new combinations of taxonomic characters is necessary. A multivariate analysis was conducted for 98 distinct populations using 20 vegetative and 43 leaf anatomical characters including PCA, PCO, CA, SIMPER and correlation analysis. The results support the recognition of four phenetic groups, which corresponds to species S. chinensis, S. reticulata, S. oblonga and S. diandra. S. acuminatissima that was recognized by Kostermans (1992) was not supported by the analysis and formed a cluster together with S. diandra with no support as a separate cluster. The study failed to recognize any distinct vegetative characters to define these taxa but propose a combination of vegetative or leaf anatomical characters and also highlights the necessity of molecular data to supplement the vegetative and leaf anatomical data to resolve the ambiguity between the S. acuminatissima and S. diandra. Bangladesh J. Plant Taxon. 28(2): 429-439, 2021 (December)

Comparative Anatomical Characteristics of the Subgenus Cyanus (Mill.) Hayek (Asteraceae) In Turkey

The identification of species based on anatomical characters is valuable to investigate their taxonomic status, phylogeny and understand their autoecology. The current study analysed the stem and leaf properties of 20 species of the subgenus Cyanus (Mill.) Hayek in Turkey. The Cyanus species exhibited xeromorphic anatomical features, such as tight palisade parenchyma and induced spongy parenchyma, which indicated adaptations to the arid soil and a forest ecosystem in which they occurred, as well as to high light intensity and precipitation. Anatomical features such as the midrib shape and number of vascularization patterns differed among the species. Similar anatomical characters were analysed for the investigated species. These properties can provide an important database for future studies including the phylogeny within the subgenus Cyanus. Bangladesh J. Plant Taxon. 28(2): 295-309, 2021 (December)

Characterization of Wild Rice - Oryza Species Complexes in Sri Lanka

Rice is the staple food crop in Sri Lanka, which occupies 34% (0.77/million ha) of the total cultivated area. Sri Lanka currently produces 2.7 million tonnes of rough rice annually and satisfies around 95% of the domestic requirement. In Sri Lanka, genus Oryza consists of two species complexes, O. sativa (AA) and O. officinalis (CC). These two complexes are both pan tropical and have very similar overall distribution. Five wild rice species are reported in Sri Lanka, (O. nivara [AA], O. rufipogan (AA) O. eichengeri [CC], O. rhizomatis (CC) and O. granulate (GG). O. rhizomatis has been reported only in Sri Lanka and considered endemic to Sri Lanka. Recent studies demonstrated, the reliance on single source of information could mislead results in the phylogenetic inferences due to analytical inconsistency and biological processes. Therefore, exact number of wild rice species in Sri Lanka becomes uncertain and the necessity arises to assess Oryza species complexes in Sri Lanka using morphological, anatomical, and molecular information to enumerate number of species within each Oryza complex and characterization of species and species complexes. The study revealed, characterization of wild rice species, to a certain extent, can be made through morphological and anatomical characters, specially lamina anatomical characters. Molecular information is more reliable in delimitation of wild rice species complexes in Sri Lanka. O. rhizomatis and O. eichingeri (CC) are well separated from the rest of wild rice species (AA). Molecular data revealed, O. nivara and O. rufipogon have undergone independent evolution within Sri Lanka. Well separated five wild rice species are existing in Sri Lanka. Studies on ecological resilience of morphological, anatomical, and molecular studies are very useful for species enumeration of wild rice complexes in Sri Lanka. The findings led to conclude that wild rice species in Sri Lanka are “ecological swarms” and represents allopatric or sympatric populations. A comprehensive knowledge on genetic diversity and population structure of wild rice germplasm in Sri Lanka provides useful information to include these locally adapted and evolved wild rice species in rice crop improvement/breeding.

Diversification of Stem Morphological and Anatomical Characteristics in Eleocharis and Related Genera (Cyperaceae, Monocotyledoneae)

Abstract— The genus Eleocharis (Cyperaceae, monocotyledons) is characterized by bladeless leaves, which are leaves having only leaf-sheaths. To study the evolutionary process through which Eleocharis species lost their leaf blades, we analyzed the outer morphological and anatomical characters of the representative Eleocharis species, plus species from nine phylogenetically related genera. From the analysis, we recognized eight characters and we optimized their character states on a recent molecular phylogenetic tree. As a result, we recognized five characteristics shared by Eleocharis species as follows: (1) the most apical internode is more than seven times longer than the next apical internode; (2) bladeless leaves having only leaf sheaths; (3) transversely septate aerenchyma in culms; (4) densely and peripherally located, slender, and square timber-shaped fiber bundles in culms; and (5) palisade chlorenchyma in culms. In these characteristics, (2) and (4) are synapomorphies of Eleocharis. These two apomorphic characteristics seemed to be adaptations for inhabiting running waters.

Morphology, anatomy and micromorphology of the genus Oliveria (Apiaceae)

Oliveria is a little-known, monotypic genus of the family Apiaceae. The only accepted species, O. decumbens, is distributed throughout Mesopotamia. It is an annual, aromatic plant that has been used in traditional medicine since ancient times. The aim of this study was to examine morphological, micromorphological, and anatomical characters of O. decumbens in order to increase the current botanical knowledge of this genus.

[New phreatic and stygobitic hydrobiids from the Northern Apennines in Piedmont, Liguria and Emilia-Romagna (Gastropoda: Caenogastropoda: Hydrobiidae)]

Five new species of phreatic and stygobitic hydrobiids are here described for the Ligurian- Piedmontese and Emilian Apennines. Two species belong to the genus Alzoniella: Alzoniella borberensis n. sp., endemic to the sub-basin of the Borbera and Spinti streams, and to the lower stretch of the Scrivia stream, in the province of Alessandria, and Alzoniella isoensis n. sp., limited to the middle course of the Scrivia stream and to the basin of the Polcevera stream, on the Tyrrhenian sector of the Genoa province. Three species belong to the genus Fissuria: Fissuria globosa n. sp., widespread throughout the sub-basin of the Scrivia stream (Genoa and Alessandria provinces), as well as in other Apennine watercourses of the provinces of Alessandria, Piacenza, Parma and Reggio Emilia; Fissuria varicosa n. sp., present in the same area of Alzoniella borberensis n. sp., but also found in the Nure and Arda streams (Piacenza province) and in the Stirone stream (Parma province), and Fissuria sossoi n. sp., limited to the sub-basin of the Stura di Ovada streams (Genoa province). The first species, assigned to the genus Alzoniella Giusti & Bodon 1984 based on its anatomical characters, has a shell with peristome detached from the last whorl, such as that of other phreatic species already known for eastern Liguria and central Italy, but differs from these in the shorter shell. The shape of the shell of A. borberensis n. sp. resembles that of other crenal or stygobitic species, widespread in northern Italy. A. isoensis n. sp., is very similar to A. borberensis, although the peristome is not sinuous superiorly on the outer edge of the shell, but differs sharply in the anatomical characters. The other taxa with valvatoid shells here described, can be ascribed to the genus Fissuria Boeters 1981 based on their anatomical characters, and show some peculiarities of the male genital tract that distinguish them from the other congeneric species so far known for southern Europe. The three new species of Fissuria differ mainly in the characters of the shell, more or less globose in F. globosa n. sp., more conical in F. sossoi n. sp. and more flattened in F. varicosa n. sp.; the latter is also characterized by the presence of a marked varix behind the peristome. Altogether, these new species can be defined as phreatic, as they colonize groundwater near watercourses; only A. isoensis n. sp. has a wider ecology, as it also lives in karst groundwater and groundwater in rocks permeable by fracking. [Article in Italian]

Ecological Adaptation of Endemic Anthocleista Species under Moisture Gradient in Parts of Niger Delta, Nigeria

Background: Knowledge of the anatomy of Anthocleista species is crucial for understanding how these plants adapt to the environment. Aim: This study was aimed at investigating the adaptive relationship of moisture gradient influence on the anatomy of four species in the genus Anthocleista (A djalonesis A Chev; A. liebrechtsiana De Wild & Th.Dur; A. nobilis G.Don; and A. vogelii Planch) in light of ecological niche adaptation. Place of Study: parts of Akwa-Ibom, Bayelsa, Cross River and Rivers States in the Niger Delta. Methods: Conventional classical anatomical techniques for structural sectioning were used. Results: Though there are similarities and differences in vascular structure among the species, the study has revealed variance in anatomical responses to moisture gradient (ranging from dry mesophytic to mesophytic and wetland conditions) of adaptation. The most important and distinct features observed are the presence of sclerenchymatous idioblast, air sacs and sclereidal idioblast. Sclerenchymatous idioblasts are numerous in A liebrechtsiana, few in A. nobilis and A. vogelii but lacking in A. djalonesis. The sclerenchymatous idioblast in A. liebrechtsiana, A. nobilis, and A. vogelii confirmed these species to be mesophytic to semi-aquatic in their habitat adaptation; while A. djalonesis is dry-mesophytic in adaptation with thicker epidermal layer, multiple hypodermal layers, thicker mesophyll tissues with increased number of palisade layers and thick leaves. The stem and root modification had abundance sclereidal idioblast distribution in A. liebrechtsiana, and A. nobilis, moderate in A. vogelii and very low in A. djalonesis. Conclusion: The variation observed in the leaf, petiole, stem and root anatomical characters are due to moisture gradient influence with the resultant effect of plant species evolving structures such as idioblast and modification to adapt to the niche and environment where they find themselves.

Anatomical Comparison of Two Grammatophyllum spp. (Orchidaceae) Species and Their Specific Ecological Adaptation

The genus Grammatophyllum (Orchidaceae) has two sections with a very different habitus. The Grammatophyllum from section “Grammatophyllum” has a long cylindrical pseudobulb with linear leaves, while the Grammatophyllum section “Gabertia” has a shorter pseudobulb with a larger diameter and broader lanceolate shaped leaves. The study is aimed to compare the anatomical characters of leaf and root between G. speciosum (representation of “Pattonia” section) and G. scriptum (representation of “Gabertia” section). Leaf and root sections were obtained using the mini-microtome with liquid preservation method in 10 replications. Data were analyzed statistically using a t-test at 5% significance. The results showed significant differences between the two species in the leaf’s primary vascular bundle area, velamen area, number of velamen layers, root’s cortex area, and stele area. Future research with more organs and parameters being explored and experimental research regarding its anatomical response to drought is suggested.