16.—The Sensory Fields and Life Mode of Phacops rana (Green, 1832) (Trilobita)

1976 ◽  
Vol 69 (16) ◽  
pp. 337-367 ◽  
Author(s):  
John Miller
Keyword(s):  
Adaptive Radiation ◽  
Sensory Function ◽  
Distinctive Pattern ◽  
General Morphology ◽  
Freedom Of Movement ◽  
Life Mode ◽  
Sensory Structures ◽  
Lateral Branches ◽  
Surface Examination ◽  
First Time

SynopsisVarious types of trilobite exoskeletal sculpture are described and referred to a simple classification. Thin-section and surface examination of many such sculptural features shows them to be remnants of distinct cuticular organelles, which probably had a sensory function. The supposed sensory structures of well-preserved specimens of Phacops rana (Green) are described in detail and their presumed specific functions considered. Mapping sensilla distribution over the Phacops rana dorsal exoskeleton shows a distinctive pattern conveniently divisible into nine inferred sensory fields with the densest sensory concentrations on the head and margins of the dorsal shield.Conclusions on the importance of these sensory fields in mediating the trilobite's behaviour are combined with evidence from general morphology, palaeocology and evolutionary trends to suggest that Phacops rana was an active benthonic animal with a dual trophic capability lending considerable flexibility in adaptive radiation.The P. rana hypostomal suture, consisting of two short coplanar lateral branches, is described for the first time, indicating that the hypostoma had considerable freedom of movement, possibly connected with ingestion of bulky food.

scholarly journals When SEM becomes a deceptive tool of analysis: the unexpected discovery of epidermal glands with stalked ducts on the ultimate legs of geophilomorph centipedes

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Andy Sombke ◽  
Carsten H. G. Müller
Keyword(s):  
Sensory Function ◽  
Sexually Dimorphic ◽  
Non Invasive ◽  
Defensive Role ◽  
Transmission Electron ◽  
Sensory Structures ◽  
Taxonomic Studies ◽  
Invasive Techniques ◽  
Epidermal Glands ◽  
Intrinsic Musculature

Abstract Background The jointed appendage is a key novelty in arthropod evolution and arthropod legs are known to vary enormously in relation to function. Among centipedes, the ultimate legs always are distinctly different from locomotory legs, and different centipede taxa evolved different structural and functional modifications. In Geophilomorpha (soil centipedes), ultimate legs do not participate in locomotion and were interpret to serve a sensory function. They can be sexually dimorphic and in some species, male ultimate legs notably appear “hairy”. It can be assumed that the high abundance of sensilla indicates a pronounced sensory function. This study seeks for assessing the sensory diversity, however, documents the surprising and unique case of an extensive glandular epithelium in the ultimate legs of three phylogenetically distant species. Results The tightly aggregated epidermal glands with stalked ducts – mistakenly thought to be sensilla – were scrutinized using a multimodal microscopic approach comprising histology as well as scanning and transmission electron microscopy in Haplophilus subterraneus. Hence, this is the first detailed account on centipede ultimate legs demonstrating an evolutionary transformation into a “secretory leg”. Additionally, we investigated sensory structures as well as anatomical features using microCT analysis. Contrary to its nomination as a tarsus, tarsus 1 possesses intrinsic musculature, which is an indication that this podomere might be a derivate of the tibia. Discussion The presence and identity of ultimate leg associated epidermal glands with stalked ducts is a new discovery for myriapods. A pronounced secretory as well as moderate sensory function in Haplophilus subterraneus can be concluded. The set of characters will improve future taxonomic studies, to test the hypotheses whether the presence of these specialized glands is a common feature in Geophilomorpha, and that tarsus 1 may be a derivate of the tibia. As the number of epidermal glands with stalked ducts is sexually dimorphic, their function might be connected to reproduction or a sex-specific defensive role. Our results, in particular the unexpected discovery of ‘glandular hairs’, may account for a striking example for how deceptive morphological descriptions of epidermal organs may be, if based on non-invasive techniques alone.

Biological, ecological, morphological and cytogenetic analyses, with taxonomic notes of Zelurus ochripennis (Stål, 1854) (Hemiptera: Heteroptera: Reduviidae: Reduviinae)

Zootaxa ◽  
2021 ◽  
Vol 4958 (1) ◽  
pp. 345-358
Author(s):  
JADER OLIVEIRA ◽  
KAIO CESAR CHABOLI ALEVI ◽  
HÉLCIO R. GIL-SANTANA ◽  
CLEBER GALVÃO
Keyword(s):  
General Morphology ◽  
Cytogenetic Data ◽  
Cytogenetic Analyses ◽  
First Time ◽  
Taxonomic Summary

Based on specimens of Zelurus ochripennis (Stål, 1854) collected in the entrance zone of a small terrestrial cave, some biological, ecological, morphological and cytogenetic data, as well, as the general morphology of their nymphs are presented for the first time. A short taxonomic summary of the species is also provided. 

scholarly journals Fine Structure of Maxillary Palps in Adults of Hermetia illucens (Diptera: Stratiomyidae)

2020 ◽  
Author(s):  
M Pezzi ◽  
C Scapoli ◽  
M Bharti ◽  
M J Faucheux ◽  
M Chicca ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sexual Dimorphism ◽  
Hermetia Illucens ◽  
The Family ◽  
Sensory Structures ◽  
First Time ◽  
Maxillary Palps ◽  
Scanning Electron

Abstract A relevant species in waste management but also in forensic, medical, and veterinary sciences is the black soldier fly, Hermetia illucens (Linnaeus; Diptera: Stratiomyidae). An ultrastructural study by scanning electron microscopy (SEM) was conducted for the first time on maxillary palps of both sexes, describing in detail the morphology and distribution of sensilla and microtrichia. The maxillary palps, composed of two segments, show sexual dimorphism in length and shape. In both sexes, the first segment is covered only by microtrichia, but the second one is divided into two parts: the proximal one, covered only by microtrichia, and the distal one containing both microtrichia and sensory structures. These structures include two types of sensory pits and one of chaetic sensilla. Due to sexual dimorphism in palp size, females have a higher number of sensory pits. The sexual dimorphism of palps and the presence and role of sensilla in H. illucens was discussed in comparison to other species of the family Stratiomyidae and of other Diptera. This study may represent a base for further investigations on mouthpart structures of this species, involved in key physiological activities, such as feeding, mating and oviposition.

scholarly journals General morphology of the oral cavity of the Nile crocodile, Crocodylus niloticus (Laurenti, 1768). I. Palate and gingivae

2003 ◽  
Vol 70 (4) ◽  
Author(s):  
J.F. Putterill ◽  
J.T. Soley
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Connective Tissue ◽  
Taste Receptors ◽  
General Morphology ◽  
Histological Features ◽  
Microscopic Features ◽  
Sensory Structures ◽  
Nile Crocodile ◽  
Scanning Electron

The heads of nine 2.5 to 3-year-old Nile crocodiles (Crocodylus niloticus) were obtained from a commercial farm where crocodiles are raised for their skins and meat. The animals from which these specimens originated were clinically healthy at the time they were slaughtered. A detailed description of the macroscopic and microscopic features of the palate and gingivae of the Nile crocodile is presented and the results are compared with published information on this species and other Crocodylia. The histological features are supplemented by information supplied by scanning electron microscopy. Macroscopic features of interest are the small conical process situated at the base of the first two incisors of the maxilla, the distribution of cobbled units on the palate, and the broad dentary shelf forming the rostral aspect of the mandible. Histologically the palate and gingivae did not differ significantly from each other and both regions showed a presence of Pacinian-type corpuscles. Two types of sensory structures (taste receptors and pressure receptors) were identified in the regions examined, both involving modification of the epithelium and the underlying connective tissue.

Description of the immature stages of Anastomoneura guahybae Huamantinco & Nessimian, 2004 (Trichoptera: Odontoceridae), with a new record for the genus and keys to larvae and pupae of Neotropical genera

Zootaxa ◽  
2006 ◽  
Vol 1362 (1) ◽  
pp. 43 ◽  
Author(s):  
LEANDRO L. DUMAS ◽  
JORGE L. NESSIMIAN
Keyword(s):  
New Record ◽  
Abdominal Segment ◽  
Minas Gerais ◽  
The State ◽  
Dorsal Spine ◽  
Gut Contents ◽  
Immature Stages ◽  
Distinctive Pattern ◽  
Lateral Carina ◽  
First Time

The larva and pupa of Anastomoneura guahybae Huamantinco & Nessimian from tributaries of the Rio Aiuruoca, Minas Gerais, Brazil, are described, illustrated and compared with other Odontoceridae. The larva is characterized by a reduced lateral carina on the head, a membranous metanotum, a distinctive pattern of ventral setae on abdominal segment I and by the presence of a conspicuous dorsal spine on the anal claw. The larva of Anastomoneura is similar to those of the neartic genera Nerophilus and Namamyia principally by the undivided mesonotal plates, and by the position and form of setal areas on the metanotum. The pupa is very similar to other odontocerids. The specimens were collected from sandy substrates in small order streams. Animal parts, plant fragments and detritus were observed in the larval gut contents. The genus Anastomoneura is for the first time recorded from the State of São Paulo, Brazil. Keys to larvae and pupae of known Neotropical genera of Odontoceridae are presented.

"The Islamic State": from Terrorism to Genocide

10.12737/6587 ◽  
2014 ◽  
Vol 2 (12) ◽  
pp. 0-0 ◽  
Author(s):  
Самвел Кочои ◽  
Samvyel Kochoi
Keyword(s):  
Mass Media ◽  
International Organizations ◽  
International Community ◽  
Islamic State ◽  
Minority Communities ◽  
Freedom Of Movement ◽  
Terrorist Organization ◽  
Terrorist Acts ◽  
Available Information ◽  
First Time

The first time in Russian legal science discusses the crimes committed by the terrorist organization “Islamic State / Islamic State of Iraq and the Levant” (IS/ISIL), against minority communities — Yazidis in Iraq. Based on the analysis of available information (reports of the UN and other international organizations, publications in Russian and foreign mass media) is substantiated conclusion about the presence of elements of the genocide in the acts of the members of the IS/ISIL. It is emphasized that the international community faced genocide, which was committed organization recognized as a terrorist. Invited to take coordinated by the international community measures to deprivation of members of the IS/ISIL freedom of movement between States and to prevent they commit terrorist acts on his return to the States, natives or citizens whom they represent.

Cilia Not Only Move, but also Have Taste!

2010 ◽  
Vol 18 (2) ◽  
pp. 6-8
Author(s):  
Stephen W. Carmichael
Keyword(s):  
Molecular Machines ◽  
Sensory Function ◽  
Mechanical Activity ◽  
Sensory Receptors ◽  
Pulmonary Infections ◽  
Immotile Cilia ◽  
Specific Direction ◽  
Motile Cilia ◽  
First Time ◽  
Sensory Functions

Motile cilia are organelles that contain amazing molecular machines that bend each cilium in a rhythmic and coordinated movement. This allows a liquid film, perhaps with particles embedded within, to move in a specific direction. The classic example is the cilia of the respiratory passages that move a layer of debris-carrying mucus out of the lungs. When this mechanism is not working properly, recurrent pulmonary infections result. The classic example of this is immotile cilia syndrome that results in chronic bronchitis and related problems. However, no sensory function has been assigned to these classic motile cilia until now (although nodal cilia have both mechanical activity and sensory functions). Alok Shah, Yehuda Ben-Shahar, Thomas Moninger, Joel Kline, and Michael Welsh have demonstrated sensory receptors on motile cilia for the first time.

Towards a Classification of the African Acacias

Bothalia ◽  
1973 ◽  
Vol 11 (1/2) ◽  
pp. 107-113 ◽  
Author(s):  
J. H. Ross
Keyword(s):  
Recent Work ◽  
Pollen Morphology ◽  
African Species ◽  
Seedling Morphology ◽  
General Morphology ◽  
First Time

Some of the first attempts to subdivide the genus Acacia Mill, as a whole are discussed briefly. Bentham’s work, in which the subdivisions of the genus were for the first time given names, is considered and his two series into which the African species fall are reproduced. The characters employed by various workers to divide the African species into two main groups are mentioned and the advantages of using each of these characters for the first dichotomy in a key are discussed. Recent work on pollen morphology and seedling morphology is correlated with general morphology. A proposal put forward by Guinet to divide Acacia into three large genera on the basis of pollen morphology is briefly discussed. Certain modifications to Bentham's series Vulgares and Gummiferae are suggested.

Meatopida gen. nov., a new genus to accommodate two species originally described in Atopida White, 1846 (Coleoptera: Scirtoidea: Scirtidae)

Zootaxa ◽  
2018 ◽  
Vol 4382 (2) ◽  
pp. 242
Author(s):  
AGATA KIAŁKA ◽  
RAFAŁ RUTA
Keyword(s):  
New Zealand ◽  
New Genus ◽  
Morphological Characters ◽  
Female Genitalia ◽  
Male And Female ◽  
Sensory Structures ◽  
First Time

The New Zealand species of marsh beetles Atopida dorsale Broun, 1893 and Atopida testacea Broun, 1880 share several features that differentiate them from other members of Atopida White. Analysis of morphological characters and the structural anatomy of the genitalia justified the description of a new genus to accommodate these two species. Sensory structures of the apical maxillary palpomere are described for the first time in Scirtidae. The presence of lacinial hooks in Scirtidae is discussed. Morphology of female prehensors is described and observations of male and female genitalia during copulation are discussed. Lectotypes of both species are designated. 

Corynotrypa from the Ordovician of North America: colony growth in a primitive stenolaemate bryozoan

1994 ◽  
Vol 68 (2) ◽  
pp. 241-257 ◽  
Author(s):  
Paul D. Taylor ◽  
Mark A. Wilson
Keyword(s):  
North America ◽  
Colony Growth ◽  
Lateral Branch ◽  
Upper Ordovician ◽  
Primary Zone ◽  
Poorly Differentiated ◽  
Lateral Branches ◽  
First Time

Colonies of the runner-like bryozoans Corynotrypa delicatula (James) and C. inflata (Hall) are common encrusters of Middle and Upper Ordovician shells and hardgrounds, especially in Cincinnatian deposits. The simplicity of their zooids contrasts with complexities in the dynamics of colonial organization. Both species have uniserial branches that bifurcate at intervals and, in addition, give rise periodically to lateral ramifications. Although angles of bifurcation and lateral ramification each average about 80°, bifurcations and lateral ramifications are fundamentally different modes of branch multiplication. In C. delicatula new lateral branches have conspicuous secondary zones of astogenetic change distinguished by elongation of successively budded zooids. Unlike bifurcations, the first zooids in lateral branches in Corynotrypa are not linked to the parent branch by a narrow basal canal, and each new lateral branch can be regarded as a distinct subcolonial unit. The ancestrula, described here for the first time in an Ordovician species of Corynotrypa, has a poorly differentiated protoecium and initiates a primary zone of astogenetic change. Colony growth in Corynotrypa was more plastic than in many other bryozoan runners. The systematics of C. delicatula and C. inflata are revised, and a lectotype is chosen for the former species.

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