Important Morphological Structures Research Articles

New and obscure species of the genus Chilocorus Mayr in eastern Asia, with the proposal of a "nitidus-group" concept (Hemiptera: Heteroptera: Cydnidae)

Comments are presented on four East-Asian species of the genus Chilocoris Mayr, of which three are known but have been hardly mentioned―namely C. alienus Horváth, C. birmanus Lis and C. nitidulus Lis. One new species is described here as C. monticola n. sp. New distribution records are provided: C. alienus is new to China (Liaoning), as well as newly representing the genus in northern China; C. birmanus is new to Taiwan; and C. nitidulus is new to Vietnam and Thailand. Until recently, C. monticola n. sp. found in Japan has been misidentified as C. nitidus Mayr, and earlier records of the latter from Japan are really this new species. Male genital structures are described and illustrated for all four species, and additionally female genital structures are also described for C. birmanus and C. monticola. These East-Asian species are significantly similar to each other in important morphological structures such as the pronotal punctuation, extension of evaporatorium, and the male and female genital organs, yet they can be distinguished from many other congeners by these same structures. It seems plausible, therefore, to group these four species in a species-group named “nitidus-group” because of the species’ definite association with C. nitidus. This species-group possibly consists at least ten East-Asian and one North American species and exhibits a relictual, trans-Beringian disjunction, suggesting an association of this group with the Tertiary circum-boreal flora. Its distributional pattern may further differentiate the species-group from other congeners.

Phylogenetic relationships of the Suidae (Mammalia, Cetartiodactyla): new insights on the relationships within Suoidea

Orliac, M. J., Antoine, P. ‐O., Ducrocq, S. (2010). Phylogenetic relationships of the Suidae (Mammalia, Cetartiodactyla): new insights on the relationships within Suoidea. —Zoologica Scripta,39, 315–330.In most analyses, both molecular and morphological phylogenies of the Cetartiodactyla support the monophyly of Suoidea. However, the evolutionary history of this superfamily remains poorly known primarily due to long‐lasting debates about the taxonomic content and relationships of the suoid families and subfamilies. Despite their crucial position in the reconstruction of the phylogeny of Cetartiodactyla, Suoidea themselves have received little attention in those phylogenies, and no extensive analysis of the group has been performed so far. We therefore examine the phylogeny of the Suidae through the first phylogenetic analysis of Suoidea, including recent and fossil representatives of all four putative families. The results support the monophyly of the traditional suid subfamilies and indicate the Sanitheriidae as sister taxon to the Suidae clade. The evolutionary history within Suidae reveals its complexity, with major convergences involving important morphological structures such as the auditory region or the upper male canine. Divergent signals gathered from either dental or cranio‐mandibular features are responsible for two long‐lasting unresolved issues within Suoidea: the question of the relationships between ‘Old World’ and ‘New World’ peccaries remaining unsolved, as well as the position and familial status of the mid‐Tertiary tayassuidPerchoerus.

The first Chinese Tarsophlebiidae from the Lower Cretaceous Yixian Formation, with morphological and phylogenetic implications (Odonatoptera: Panodonata)

The Early Cretaceous Turanophlebia sinica sp. nov. is the first Chinese representative of the enigmatic family Tarsophlebiidae. The exquisite preservation of the type specimen allows to precise several important morphological structures of phylogenetic importance, i.e. three-segmented tarsi, with basal tarsomere very long; and absence of subapical tooth on tarsal claw. If the first character not longer supports a basal position for Tarsophlebiidae, the second confirms it. The presence of a fore leg tibial comb supports the hypothesis that the reduced tibial comb of the Hemiphlebiidae is apomorphic for this last group.

Automated image analysis as a tool to quantify the colour and composition of rainbow trout ( Oncorhynchus mykiss W.) cutlets

The goal of this paper is to propose and evaluate automated image analysis methods for describing muscle cutlets in rainbow trout. The proposed automated image analysis methods were tested on a total of 983 scanned images of trout cutlets, and included quality traits such as fat percentage, flesh colour and the size of morphologically distinguishable subparts of the cutlet. A sub-sample of 50 images was randomly selected for manual segmentation of the cutlet, the dorsal fat depot and the red muscle and regions. The identification of these regions by manual and automatic image analysis correlated strongly ( r = 0.97, r = 0.95 and r = 0.91, respectively). The estimated fat percentage obtained from image analysis, based on the area of visible fat and the colour of the cutlet flesh, correlated well with chemical fat percentage measured by mid-infrared transmission spectroscopy (MIT) ( r = 0.78). The automated image analysis methods are therefore a reliable means of predicting the fat percentage of trout cutlets. Principal component analysis (PCA) loading plots were used to identify subsets of variables from the image analysis of special significance for further studies; cutlet area, dorsal fat depot area, red muscle area, back height, cutlet width, and width of left and right abdomen wall were among the variables selected. PCA loading plots of different colour variables indicated that simple statistical coefficients such as percentiles and mean values can be used to quantify different aspects of flesh colour. In conclusion, the methods presented here provide a powerful toolbox for describing important morphological structures and quality traits of trout cutlets.

Observation of some key stages of the embryonic development of Biomphalaria straminea (Dunker, 1848) (Molluska, Planorbidae)

Summary Biomphalaria straminea is a freshwater snail and one of the intermediate hosts of the trematode parasite which causes schistosomiasis in Brazil. The main stages of embryonic development were analyzed with confocal laser scanning microscopy (CLSM), using the fluorescent probe DiOC and Nile Red as a vital stain in in vivo preparations. In fixed preparations nuclei were stained by the Feulgen reaction or the fluorescent DNA probe, Höechst 33342. Results obtained from the analysis of embryos at the stages of early cleavage, morula, blastula, gastrula, early trocophore and veliger showed that these stages are similar to those described for Biomphalaria glabrata and Biomphalaria tenagophila. CLSM optical sections of early trochophore showed important morphological structures such as the blastopore, stomodeum and shell gland; and in early veliger, internal organs such as the esophagus, stomach and male and female ducts were also clearly identified.

MADS‐BOX GENES: DEVELOPMENT AND EVOLUTION OF PLANT BODY PLANS

We review functional data on MADS‐box genes, recent phylogenetic analyses of these coding regions, and their roles in the development and evolution of key morphological innovations in plants. We map the origin of important morphological structures in particular diverse stages of the life cycle in different plant clades onto organismal phylogenies, and present relevant molecular genetic aspects of development related to the MADS‐box genes. We focus on reproductive structures of the sporophyte because most functional characterizations have been done of MADS‐box genes involved in flower development. We discuss MADS‐box evolution in flowering plants, but we also review studies in the other nonflowering vascular plants, gymnosperms (conifers and gnetales), and ferns and preliminary data from the algae. We suggest that floral (e.g. flowering time, inflorescence, and flower meristem identity) MADS‐box and nonfloral plant MADS‐box genes should be the focus of future comparative research. Cloning and functional analyses of MADS‐box genes in bryophytes, particularly in the experimental system Physcomitrella patens (Hedw.) B.S.G., are needed. The ABC model of floral organ specification is an excellent general representation of an important network of genes; however, formal analytical tools are required to integrate data on complex gene interaction in comparative analyses. This and other analytical approaches to constructing gene network models will help to frame homology hypotheses in an evolutionary and developmental framework.

Finite-Element Modeling of the human neurocranium under functional anatomical aspects

Due to its functional significance the human skull plays an important role in biomechanical research. The present work describes a new Finite-Element model of the human neurocranium. The dry skull of a middle-aged woman served as a pattern. The model was developed using only the preprocessor (Mentat) of a commercial FE-system (Marc). Unlike that of other FE models of the human skull mentioned in the literature, the geometry in this model was designed according to functional anatomical findings. Functionally important morphological structures representing loci minoris resistentiae, especially the foramina and fissures of the skull base, were included in the model. The results of two linear static loadcase analyses in the region of the skull base underline the importance of modeling from the functional anatomical point of view.

Characterization of Black Nightshade (Solanum nigrum) and Related Species in the United States

Information from taxonomic treatments and comparisons of accessions from numerous locations grown in the field and greenhouse were combined and summarized to produce a key and descriptions of common agricultural nightshades in North America (Solanum americanumMill.,S. nigrumL.,S. ptycanthumDun., andS. sarrachoidesSendt.). Quantitative and qualitative descriptions of key characters and photographs of important morphological structures are provided to facilitate field identification. Problems with nomenclature among these species are discussed, and a system of common names that would standardize usage is proposed.