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1

Functional morphology of the upper and lower eyelids, third eyelid, lacrimal gland and superficial gland of the third eyelid in the red kangaroo (Macropus rufus)

100%
Kleckowska-Nawrot J., Gozdziewska-Harlajczuk K., Barszcz K., Janeczek M.
Folia Biologica
|
2016
|
tom 64
|
nr 3
2

Fish caeca: a review of their history, evolution and functional morphology

100%
Hossain A. M., Dutta H. M.
Bulletin of the Polish Academy of Sciences. Biological Sciences
|
1991
|
tom 39
|
nr 4
3
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Oviraptorosaur tail forms and functions

84%
Persons,IV W. S., Currie P. J., Norell M. A.
Acta Palaeontologica Polonica
|
2014
|
tom 59
|
nr 3
Oviraptorosaur caudal osteology is unique among theropods and is characterized by posteriorly persistent and exceptionally wide transverse processes, anteroposteriorly short centra, and a high degree of flexibility across the pre-pygostyle vertebral series. Three-dimensional digital muscle reconstructions reveal that, while oviraptorosaur tails were reduced in length relative to the tails of other theropods, they were muscularly robust. Despite overall caudal length reduction, the relative size of the M. caudofemoralis in most oviraptorosaurs was comparable with those of other non-avian theropods. The discovery of a second Nomingia specimen with a pygostyle confirms that the fused terminal vertebrae of the type specimen were not an abnormality. New evidence shows that pygostyles were also present in the oviraptorosaurs Citipati and Conchoraptor. Based on the observed osteological morphology and inferred muscle morphology, along with the recognition that many members of the group probably sported broad tail-feather fans, it is postulated that oviraptorosaur tails were uniquely adapted to serve as dynamic intraspecific display structures. Similarities, including a reduced vertebral series and a terminal pygostyle, between the tails of oviraptorosaurs and the tails of theropods widely accepted as basal members of the Avialae, appear to be convergences.
4

Morphological specializations of Cheiromeles (naked bulldog bats; Molossidae) and their possible role in quadrupedal locomotion

84%
Schutt,Jr. W. A., Simmons N. B.
Acta Chiropterologica
|
2001
|
tom 03
|
nr 2
Two molossids, Cheiromeles torquatus and C. parvidens, display a number of morphological characteristics that appear unique among Chiroptera. In this study, adult specimens of both species (fluid-preserved and skeletons) were examined using a dissecting microscope and camera lucida. Several unique morphological features are described in detail for the first time with comments on their possible functions. These include a hallux (digit I) that is positioned at a right angle to digits II-V, a calcar that is bound to m. gastrocnemius, and a modified m. tensor plagiopatagii which appears to function like a drawstring to close a pair of subaxillary 'pouches'. The function of these structures and additional characteristics of the limbs appear related to terrestrial and arboreal locomotion exhibited by these bats.
5
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Flowering biology and pollen production of four species of the genus Rosa L.

84%
Zuraw B., Sulborska A., Stawiarz E., Weryszko-Chmielewska E.
Acta Agrobotanica
|
2015
|
tom 68
|
nr 3
Wild growing rose species are of great importance as a source of pollen for insects. Oil extracted from the petals of various Rosa species is used in perfumery, cosmetic industry, and therapeutics. In our study, we compared the flowering duration and flower lifespan, the number of stamens and pistils, the mass and size of pollen grains as well as the anatomical features of the petals of four Rosa species: R. canina, R. ×damascena, R. gallica, and R. rugosa. Moreover, we examined the pollen loads collected by bumblebees foraging on rose flowers in order to determine the attractiveness of pollen of this genus to insects. We showed the flower lifespan to vary (3.5–8 days) in the roses studied and revealed high variation in the number of stamens (82–260) and pistils (17–65) as well as in the mass of pollen produced. The flowers of R. rugosa produced the highest amount of pollen (26.7 mg per flower), while the flowers of R. canina the least (3.3 mg per flower), which is associated with differences in the number of stamens developed in the flowers between these species. The largest pollen grains were found in R. ×damascena and R. gallica. We demonstrated that R. ×damascena produces the thickest petals and that scent-emitting papillae found on the adaxial surface of the petals differ in size and shape in the rose species investigated.
6
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'Plastrons and adhesive organs' - the functional morphology of surface structures in the broad mite, Polyphagotarsonemus latus (Banks, 1904)

84%
Baker R. A.
Zeszyty Naukowe. Acta Biologica. Uniwersytet Szczeciński
|
2012
|
tom 19
Consideration is given to the structure and function of the adhesive organ in the male and of the protuberances on the surface of the egg in the Broad mite, Poly phagotarsonemus latus . Scanning Electron microscopy is used to reveal these structures. The adhesive organ serves as a sucker in order that males can carry pharate females. It is believed that the protuberances are part of a discontinuous plastron for gaseous exchange.
7

Functional morphological characteristics of the interdigital sinus in the sheep

84%
Pourlis A. F.
Folia Morphologica
|
2010
|
tom 69
|
nr 2
The present paper describes two distinct morphological features of ovine interdigital sinus, which were examined by means of scanning electron microscopy. In the sweat glandular component, acini with epithelial cells exhibiting a paved appearance and apocrine secretion were observed. In the same gland, other acini with cells exhibiting different luminal surfaces and simultaneous apocrine and merocrine secretion were recorded. The numerous hairs embedded within the waxy material of the sinus exhibited two types. The first type, with a round profile, had a special leaflet structure on the tip, whereas the second type had a convex profile. The comparative differences and probable functional relations of these integumentary structures are discussed. The mixed picture of the epithelial cells of the sweat glands suggests the release of different products. The hair microstructure correlated with the mechanism of hold and release of the secretory material of the interdigital sinus. (Folia Morphol 2010; 69, 2: 107–111)
8
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Aspects of life mode among Ordovician asteroids: Implications of new specimens from Baltica

84%
Blake D. B., Rozhnov S.
Acta Palaeontologica Polonica
|
2007
|
tom 52
|
nr 3
A new genus and species of Asteroidea (Echinodermata), Estoniaster maennili, is described from the Upper Ordovician (Caradocian) of Estonia; it is similar to the western European genus Platanaster and the North American Lanthanaster and an as yet unpublished new genus. Specimens of Urasterella? sp. and Cnemidactissp. are recognized from the Middle Ordovician of northwest Russia; although similar to known species, incomplete preservation precludes more precise taxonomic assessment. Asteroids are important in many existing marine communities, and in spite of a meager fossil record, diversity suggests they were important in the early Paleozoic as well. Some debate has centered on arm flexibility in early asteroids, which bears on their roles in their communities. Parallels in ambulacral series arrangement between Ordovician and extant species and presence of an ambulacral furrow indicate similar broad ranges of motion and therefore potentially parallel ecologic roles. Many factors might have contributed to the differences between ancient and extant ambulacral articulation, including changes in positioning of a part of the water vascular system, changes in predation and bioturbation pressures, and taphonomic events that obscure skeletal details.
9

Phenetic relationships among bats of the family Rhinolophidae

84%
Bogdanowicz W.
Acta Theriologica
|
1992
|
tom 37
|
nr 3
10
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Evidence for a sauropod-like metacarpal configuration in stegosaurian dinosaur

67%
Senter P.
Acta Palaeontologica Polonica
|
2010
|
tom 55
|
nr 3
427-432
The stegosaurian forelimb is usually portrayed with the metacarpals slanted and distally spread. However, manual manipulation of stegosaurian metacarpals reveals that in that configuration they do not articulate with each other nor with the rest of the forelimb. Rather, they do articulate with each other and with the rest of the forelimb when posed vertically and arranged in a compact, semi−tubular configuration, as in sauropods. This configuration agrees with data from articulated specimens and trackways. As with sauropods, this metacarpal configuration makes retention of phalanges awkward for locomotion and may be functionally related to the vestigiality of the manual phalanges of the outer digits.
11
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Functional morphology and modifications on spine growth in the productid brachiopod Heteralosia slocomi

67%
Perez-Huerta A.
Acta Palaeontologica Polonica
|
2013
|
tom 58
|
nr 2
Spines are one of the most characteristic ornamenting features of many fossil brachiopod taxa. Despite several studies of spines in different species, there is still insufficient information about the development, functionalmorphology, andmodifications of brachiopod spines. In particular, ontogenetic data are very rare and the understanding of the relationship between functional morphology and paleoecology is elusive. The present study analyzes the functional morphology and modifications on spines of the Pennsylvanian brachiopod species Heteralosia slocomi throughout ontogeny. Spines are tubular hollow and only displayed on the surface of the ventral valves, where they develop from a specific point at the margins of the growth lamellae and directed towards the anterolateral margins.Modifications of up to 180 from this original direction of growth are observed in response to ecological pressure and biotic interactions. The function of these spines is primarily for attachment by clasping and cementation, but the possibility of spines acting as sensory mechanisms is not excluded.
12
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Functional morphology and biomechanics of the cynodont Trucidocynodon riograndensis from the Triassic of Southern Brazil: Pectoral girdle and forelimb

67%
de Oliveira T. V., Schultz C. L.
Acta Palaeontologica Polonica
|
2016
|
tom 61
|
nr 2
Non-mammalian cynodonts provide insights on several points about mammalian evolution, such as the postural change and locomotory advances within the group. Unfortunately, complete skeletons of Triassic cynodonts are rather uncommon and where more complete specimens are found they can offer a global vision on some traits not available from partial specimens. This is the case of the cynodont Trucidocynodon riograndensis, from the Triassic of Brazil, that has preserved its forelimbs providing some insights into locomotory properties. The movements between interclavicle and clavicle must have been limited, as such as those occurring between the latter and the scapulocoracoid although the long acromion process of this should have permitted a greater degree of freedom. Some of the more significant movements were those on the shoulder joint, in which the maximum adduction should have been ca. 35º relative to the parasagittal plane and the greater abduction ca. 55º. The maximum adduction occurred when the humerus was in the more retracted position during stride and the variation in the adduction/abduction should have been significant to the limb posture during its recovery stroke. The long olecranon and the distal overlapping between radius and ulna suggest the predominance of simple flexion/extension on the forearm without significant pronation/supination. The poorly preserved hand suggests that Trucidocynodon could have evolved a slight semidigitigrad condition in its forelimbs. All these features give to this cynodont an important role in the evolution of the mammalian locomotory properties indicating that some features, such as the possibility of greater humeral adduction, evolved early in cynodont lineage.
13

Ultastructure of the ventral lateral geniculate nucleus [LGNv] receiving tectal afferents in the cat

67%
Noseworthy M. D., Partlow G. D.
Acta Neurobiologiae Experimentalis
|
1992
|
tom 52
|
nr 2
14
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The hind limb skeleton and cursorial adaptations of the Plio-Pleistocene rabbit Hypolagus beremendensis

67%
Fostowicz-Frelik L.
Acta Palaeontologica Polonica
|
2007
|
tom 52
|
nr 3
Hypolagus beremendensis, a representative of the Archaeolaginae, was one of the most abundant and widespread leporids in the Plio−Pleistocene of Europe. The vast accumulations of skeletal remains from the Polish Pliocene sites (Węże 1, Rębielice Królewskie 1 and 2, and Kadzielnia 1) yielded thousands of bones representing almost all skeletal regions. The detailed hind limb morphology of Hypolagus beremendensisis presented in comparison with five extant leporids (Lepus europaeus, Oryctolagus cuniculus, Pentalagus furnessi, Sylvilagus floridanus, and S. brasiliensis), which represent a wide range of locomotor adaptations. The UPGMA analysis of 98 metric characters places Hypolagus beremendensis next to the leporine rabbits. Hypolagus beremendensis has the os coxae, femur, and talus most similar to P. furnessi, tibia and calcaneus to the leporine rabbits, and the structure of foot to Lepus. The elongation of the foot and tibiofibular segment in relation to the femur indicates an advanced cursorial adaptation and a relatively steep jump. The similarities in the proximal segments (os coxae and femur) between Hypolagus and Pentalagus highlight the conservative morphology of this region in the Leporidae.
15
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A new Middle Cambrian stem-group echinoderm from Spain: Palaeobiological implications of a highly asymmetric cinctan

67%
Zamora S., Smith A. B.
Acta Palaeontologica Polonica
|
2008
|
tom 53
|
nr 2
A new exquisitely preserved stem group echinoderm (cinctan), Lignanicystis barriosensis gen. et sp. nov., is described from the Middle Cambrian of Los Barrios de Luna, North Spain. This displays a unique asymmetrical body plan with ventral projecting nodes that raised the lower surface above the substratum. There are four openings through the body wall: mouth, anus, atrium, and an aligned row of sutural pores of uncertain function. Unlike other cinctans, Lignanicystis has a strongly asymmetrical shape convergent with that of some cornute carpoids. Like cornutes, the test is also elevated above the substratum to allow water flow beneath the theca. In both cases this is probably an adaptation to life in higher water flow regimes.
16

Two new species of entobdelline skin parasites [Monogenea, Capsalidae] from the blotched fantail ray, Taeniura meyeni, in the Pacific Ocean, with comments on spermatophores and the male copulatory apparatus

59%
Whittington I. D., Kearn G. C.
Acta Parasitologica
|
2009
|
tom 54
|
nr 1
12-21
We made a comparative anatomical study of entobdelline monogenean skin parasites from the blotched fantail ray, Taeniura meyeni (= T. melanospila) from public aquaria and fish-holding facilities distributed widely across the western Pacific Ocean. These facilities were located in Australia (Mooloolaba, southern Queensland; Cairns, northern Queensland), Taiwan and Japan. The capture localities of the aquarium fishes are unknown to us, with the exception of the individual fish from northern Queensland which came from Sudbury Reef, a local inshore reef. Entobdellines from southern Queensland differed morphologically from those from northern Queensland and Taiwan and the 2 new monogenean species are described and named Neoentobdella garneri sp. nov. and N. taiwanensis sp. nov., respectively. We determined that an entobdelline collected by Dyer and co-workers from a ray identified as T. melanospila (= T. meyeni) from an aquarium in Okinawa, Japan and identified by them as Entobdella squamula (Heath, 1902) Johnston, 1929 was misidentified and is tentatively assigned to N. taiwanensis sp. nov. The male copulatory organ of each new species resembles a penis, but evidence that these organs are eversible like a cirrus is presented. Caution is advised in deciding whether the male copulatory organs of capsalids may function as a penis or as a cirrus and we suggest that possession of a penis versus a cirrus may not necessarily indicate wide evolutionary divergence. In N. garneri, spermatophores consist of a sausage-shaped capsule and a long hollow stalk. A spermatophore received from a donor is anchored in the vagina by means of the stalk, with the capsule protruding outside the body.
17
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Carnassiform notches improve the functional efficiency of bat molar shearing crests

59%
Czaplewski N. J., Baker C. G.
Acta Palaeontologica Polonica
|
2022
|
tom 67
|
nr 1
18
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Functional morphology and taphonomy of nautiloid beaks from the Middle Triassic of Southern Germany

59%
Klug C.
Acta Palaeontologica Polonica
|
2001
|
tom 46
|
nr 1
New records of nautiloid beak elements conventionally classified as 'Rhyncholithes hirundo (Biguet, 1819)' and 'Conchorhynchus avirostris (von Schlotheim, 1820)' with carbonised (originally chitinous) three-dimensionally preserved appendages from the Upper Muschelkalk (Middle Triassic) of northern Württemberg (Southwest Germany) enable restoration of the complete beak of Germanonautilus. In three specimens, the lower mandible is embedded within the living chamber of Germanonautilus conchs, Beak elements of Germanonautilus differ from those of Recent Nautilus in the more elongate appendages of the fossil lower mandibles and the weaker sculpture on the originally chitinous parts. Furthermore, the dorsal sculpture of the fossil conchorhynchs consists of ridges rather than denticles and the ventral sculpture of the fossil rhyncholiths displays ridges in places where the Recent rhyncholiths have a smooth surface. Additionally, the fossil beak elements attained a larger size than their Recent counterparts, During transport of 'Rhyncholithes hirundo', the light chitinous parts served as a sail and the heavier conchorhynch anchored in the sediment causing alignment. In contrast to the irregularly embedded isolated rhyncholiths, the conchorhynchs usually settled with their ventral side up. From the study of 407 fossil nautiloid beak-elements, a significant variability of the hard parts is evident. Consequently, the assignment of specific morphologies to the species of Germanonautilus is impossible.
19
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Pneumaticity and soft-tissue reconstructions in the neck of diplodocid and dicraeosaurid sauropods

59%
Schwarz D., Frey E., Meyer C. A.
Acta Palaeontologica Polonica
|
2007
|
tom 52
|
nr 1
The axial soft−tissue system in the neck of Dicraeosauridae and Diplodocidae, including pneumatic diverticula, ligaments, and muscles, is reconstructed on the basis of phylogenetic and functional morphological comparisons with extant crocodylians and birds and compared with other soft−tissue reconstructions for sauropods. Bifurcation of the neural spines separated the paired supraspinal ligament into two sheets. A paired interspinal septum was attached to the cranial and caudal margins of the neural spines. The dorsal and the lateral portions of the cervical musculature must have been strongly segmented, whereas the laterocostal portion was divided with one myoseptum per vertebral segment. The hypaxial cervical muscle was most probably small and only poorly segmented. In Diplodocidae and Dicraeosauridae, the distribution of external pneumatic structures is similar, whereas only Diplodocidae possess intraosseous pneumatic structures. Supravertebral pneumatic diverticula are reconstructed for both groups, which, together with dorsal ligaments filled the gap between the metapophyses of bifurcate neural spines. Comparisons between the vertebrae of juvenile and adult diplodocids strongly indicate that pneumatisation proceeded from the supramedullary diverticula into the neural arch and the neural spine. The regular branching pattern of the pneumatic cavities as well as the vertical I−beam construction of the vertebral corpora is interpreted as a consequence of the biomechanical constraints of the vertebral corpora in diplodocids. These reconstructions form the ground for functional morphological considerations in Diplodocidae and Dicraeosauridae while addressing the possible mechanical consequences of pneumatic structures for the integrity of the support system of the neck.
20

A new genus and new species of microbothriid monogenean [Platyhelminthes] with a functionally enigmatic reproductive system, parasitic on the skin and mouth lining of the largetooth sawfish, Pristis microdon, in Australia

51%
Kearn G. C., Whittington I. D., Evans-Gowing R.
Acta Parasitologica
|
2010
|
tom 55
|
nr 2
115-122
Dermopristis paradoxus gen. et sp. nov., a microbothriid monogenean parasite from the skin and mouth lining of the largetooth sawfish, Pristis microdon (Elasmobranchii, Pristidae) in Australia, is described. The parasite has 2 juxtaposed testes and differs from other microbothriids in possessing a unique and unusual terminal male reproductive tract comprising a proximal and a distal tube, the latter with a conspicuous opening on the ventral surface and lacking a recognisable male copulatory organ. The smalltooth sawfish, P. pectinata, also has a skin-parasitic microbothriid, Dermophthirioides pristidis Cheung et Nigrelli, 1983, but this parasite species has a prominent copulatory papilla. Dermopristis paradoxus also has parallel ridges with broad tops running in a roughly transverse direction across the ventral surface of the body. The ventral ridges are prominent from the level of the pharynx to the posterior region of the body. The function of the ridges is unknown. Reproductive biology, attachment and feeding in D. paradoxus are discussed. In the absence of unmounted parasite specimens for sectioning, a mounted specimen of D. paradoxus was released from the slide and successfully processed to provide serial, stained, resin sections. This useful technique is recommended to provide anatomical information in situations where only specimens on slides are available for study.
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