Ultrastructure and tubulin immunocytochemistry of the copulatory stylet-like structure in Childia species (Acoela).

Abstract:

:One of the main characters used in acoel taxonomy is the male copulatory organ. Despite this, ultrastructural studies of this structure are scarce. We studied the ultrastructure of the copulatory organ in eight species of acoels belonging to the taxon Childia. Members of Childia possess a well-developed conical or cylindrical stylet-like structure composed of needles. Immunogold cytochemistry of tubulin was used to determine the composition of the needles. Stylet-like structures of Childia species at the ultrastructural level are basically similar. Stylet needles show intracellular differentiations. As shown both by ultrastructural and immunocytochemical methods, the stylet needles, in all species studied, are composed of long, parallel microtubules, either tightly packed or polymerized. We report unusual polymerization of microtubules, resulting in formation of a honeycomb-like structure in cross section. Variations of ultrastructure among Childia species include numbers and arrangement of stylet needles, shape of needles, needle compactness, microtubule polymerization, direction of stylet growth, and presence/absence of different types of granules. The stylet-like structures are homologous within Childia, but are likely to prove nonhomologous with the other needle-like structures found in acoel copulatory organs. Stylets in Platyhelminthes are not homologous with stylet-like structures in acoels.

journal_name

J Morphol

journal_title

Journal of morphology

authors

Tekle YI,Raikova OI,Justine JL,Jondelius U

doi

10.1002/jmor.10502

subject

Has Abstract

pub_date

2007-02-01 00:00:00

pages

166-80

issue

2

eissn

0362-2525

issn

1097-4687

journal_volume

268

pub_type

杂志文章
  • Homology and evolution of the deep dorsal thigh musculature in birds and other reptilia.

    abstract::Data from adult birds, crocodilians, Sphenodon, squamates, turtles, and from the chick embryo are compared to test conflicting hypotheses of homology of the deep dorsal thigh muscles of birds and other reptiles. This comparison suggests that: (1) avian Mm. iliofemoralis externus and iliotrochantericus caudalis (herein...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1051890310

    authors: Rowe T

    更新日期:1986-09-01 00:00:00

  • Do all geckos hatch in the same way? Histological and 3D studies of egg tooth morphogenesis in the geckos Eublepharis macularius Blyth 1854 and Lepidodactylus lugubris Duméril & Bibron 1836.

    abstract::The egg tooth of squamates evolved to facilitate hatching from mineralized eggshells. Squamate reptiles can assist their hatching with a single unpaired egg tooth (unidentates) or double egg teeth (geckos and dibamids). Egg tooth ontogeny in two gekkotan species, the leopard gecko Eublepharis macularius and the mourni...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.21249

    authors: Hermyt M,Metscher B,Rupik W

    更新日期:2020-10-01 00:00:00

  • The functional anatomy of the hindlimb of some African Viverridae (Carnivora).

    abstract::The functional anatomy of the hindlimb of 12 species of viverrids was studied with relation to locomotion. The animals were allocated to primary locomotor categories on the basis of their anatomy and locomotion. The climbing, arboreal walking category (Nandinia binotata) is characterized by a small sacroiliac articula...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1051480208

    authors: Taylor ME

    更新日期:1976-02-01 00:00:00

  • Distribution and innervation of short, interdigitated muscle fibers in parallel-fibered muscles of the cat hindlimb.

    abstract::The cat hindlimb contains several long, biarticular strap muscles composed of parallel muscle fascicles that attach to short tendons. Three of these muscles--sartorius, tenuissimus, and semitendinosus--were studied by dissecting individual gold-stained fibers and determining the surface distribution of acetylcholinest...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1051910102

    authors: Loeb GE,Pratt CA,Chanaud CM,Richmond FJ

    更新日期:1987-01-01 00:00:00

  • Ovary of the seahorse, Hippocampus erectus.

    abstract::The ovary of the seahorse, Hippocampus erectus, is a cylindrical tube bounded by an outer layer consisting of a mesothelium and muscular wall and by an inner luminal epithelium, with a single row of developing follicles sandwiched between the two layers. Follicles are produced by a germinal ridge, which contains oogon...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1052090305

    authors: Selman K,Wallace RA,Player D

    更新日期:1991-09-01 00:00:00

  • Comparative postnatal ontogeny of the skull in the australidelphian metatherian Dasyurus albopunctatus (Marsupialia: Dasyuromorpha: Dasyuridae).

    abstract::We describe the cranial ontogeny of an australidelphian marsupial, Dasyurus albopunctatus, using a combination of qualitative and quantitative approaches. We examined in detail qualitative morphological changes of just-weaned individuals as compared to old adults; specifically, changes in 31 morphological structures (...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10420

    authors: Flores DA,Giannini N,Abdala F

    更新日期:2006-04-01 00:00:00

  • Kinematics and morphology: A comparison of 3D-patterns in the fifth pereiopod of swimming and non-swimming crab species (Malacostraca, Decapoda, Brachyura).

    abstract::Swimming crabs of the taxon Portunoidea show specialized, paddle-shaped fifth pereiopods (P5), which play a role in these crabs' ability to swim. In this study, the morphology of the fifth pereiopod in swimming and non-swimming crabs was studied in detail and the mobility in the articulations between podomeres was cal...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.21268

    authors: Schmidt M,Hazerli D,Richter S

    更新日期:2020-12-01 00:00:00

  • External genital morphology of the ring-tailed lemur (Lemur catta): females are naturally "masculinized".

    abstract::The extravagance and diversity of external genitalia have been well characterized in male primates; however, much less is known about sex differences or variation in female form. Our study represents a departure from traditional investigations of primate reproductive anatomy because we 1) focus on external rather than...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10594

    authors: Drea CM,Weil A

    更新日期:2008-04-01 00:00:00

  • Geometric morphometric analysis as a proxy to evaluate age-related change in molar shape variation of low-crowned Notoungulata (Mammalia).

    abstract::Shape and age variation in dentition of Paleogene extinct native South American ungulates (Notoungulata) has been traditionally described using qualitative and quantitative approaches, and has played a controversial role in the systematics of several groups. Such is the case of the Notopithecidae, a group of notoungul...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.20766

    authors: Scarano AC,Vera B

    更新日期:2018-02-01 00:00:00

  • Ultrastructural description of the spermatogenesis and spermatozoa in Phaenocora unipunctata (Platyhelminthes, Neotyphloplanida).

    abstract::Ultrastructural studies of spermiogenesis and sperm morphology have found many characters that are likely to provide clues to the phylogeny of the Platyhelminthes. However, the lack of information on many free-living groups has been a limiting factor. There is a single description of the spermatogenesis and spermatozo...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.20800

    authors: Ponce de León R,Volonterio O

    更新日期:2018-05-01 00:00:00

  • Morphology and histology of the male reproductive system in two species of internally inseminating South American catfishes, Trachelyopterus lucenai and T. galeatus (Teleostei: Auchenipteridae).

    abstract::As part of an effort to characterize reproductive modifications in internally inseminating catfishes, ovaries and male reproductive systems were examined histologically in two species of auchenipterid catfishes, Trachelyopterus lucenai and T. galeatus, from southeastern Brazil. Internal insemination was documented in ...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/1097-4687(200011)246:2<131::AID-JMOR7>3.0.

    authors: Downing Meisner A,Burns JR,Weitzman SH,Malabarba LR

    更新日期:2000-11-01 00:00:00

  • Ventral neurons in the anterior nerve cord of amphioxus larvae. I. An inventory of cell types and synaptic patterns.

    abstract::Serial sections were used to map the ventrally positioned neurons of the anterior nerve cord of a 12.5-day amphioxus larva from the infundibular region to the end of somite 2. Synaptic patterns reveal five categories of descending pathways, four of which are associated with the ventral compartment (VC) motoneurons res...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10114

    authors: Lacalli TC,Kelly SJ

    更新日期:2003-08-01 00:00:00

  • Mastication in springhares, Pedetes capensis: A cineradiographic study.

    abstract::Analysis of lateral and dorsoventral radiographic films shows that ingestion, transport, and mastication in Pedetes capensis (Rodentia) are cyclic and their movement patterns are essentially similar for the three food types offered. During the ingestion cycle, closing of the mouth is accompanied by a backward translat...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1052050310

    authors: Offermans M,de Vree F

    更新日期:1990-09-01 00:00:00

  • Comparative study of dentition among species of Poecilia (Pisces).

    abstract::Many studies in the genus Poecilia have focused on reproductive and genetic characteristics of Poecilia formosa, the Amazon molly, and its sympatric species P. latipinna and P. mexicana. The research literature of Poecilia dentition has been limited to general tooth morphology. Essentially absent are comparative analy...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/(SICI)1097-4687(199903)239:3<271::AID-JMOR

    authors: Lewis SR,Rasch EM,Hossler FE,Kalbfleisch JH,Monaco PJ

    更新日期:1999-03-01 00:00:00

  • Internal architecture, origin-insertion site, and mass of jaw muscles in Old World hamsters.

    abstract::The jaw muscle (i.e., masticatory, suprahyoid, and extrinsic tongue) anatomy and mass were examined in four genera of Old World hamsters (cricetine murids), Mesocricetus, Cricetulus, Tscherskia, and Phodopus. The masseter was the largest and most complicated of the muscles examined. In the superficial layer, a few ven...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10198

    authors: Satoh K,Iwaku F

    更新日期:2004-04-01 00:00:00

  • Reproductive role of attaching filaments on the egg envelope in Xenopoecilus sarasinorum (Adrianichthidae, teleostei).

    abstract::Eggs of Xenopoecilus sarasinorum possess two distinct types of filaments on the surface of the egg envelope (chorion), long, attaching filaments restricted to the vegetal pole and weak, nonattaching filaments around the animal pole (micropyle). Both types are formed during oogenesis. After mature eggs were spawned thr...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10620

    authors: Iwamatsu T,Kobayashi H,Sato M,Yamashita M

    更新日期:2008-06-01 00:00:00

  • Internal anatomy and ultrastructure of the male reproductive system of the Norway lobster Nephrops norvegicus (Decapoda: Astacidea).

    abstract::The Norway lobster (Nephrops norvegicus) is economically important in Europe. However, apart from the female reproductive system, very little is known about its internal anatomy. This article focuses on studying the internal anatomy and ultrastructure of the male reproductive system. This system follows the general pa...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.20002

    authors: Rotllant G,Chiva M,Durfort M,Ribes E

    更新日期:2012-06-01 00:00:00

  • Attachment and metamorphosis of the cheilo-ctenostome bryozoan bugula neritina (linné).

    abstract::The structure, attachment and subsequent metamorphosis of larvae of the marine bryozoan Bugula neritina were studied by light and electron microscopy. Two points of larval anatomy are of special significance to proper interpretation of the metamorphosis: 1 Two cytologically similar blastemal tissues, each laden with f...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1051340307

    authors: Woollacott RM,Zimmer RL

    更新日期:1971-07-01 00:00:00

  • Ultrastructure of spermatogenesis in the short-tailed fruit bat, Carollia perspicillata (Chiroptera: Phyllostomidae: Carollinae).

    abstract::Among species of the Chiroptera, spermatogenesis and the fully differentiated spermatozoa differ in morphological and ultrastructural detail. This study therefore aimed to ultrastructurally characterize the spermatogenesis and the spermatozoa of Carollia perspicillata (Phyllostomidae) and compare the process with othe...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.20202

    authors: Beguelini MR,Bueno LM,Caun DL,Taboga SR,Morielle-Versute E

    更新日期:2014-01-01 00:00:00

  • The organization of the octavolateralis area in actinopterygian fishes: A new interpretation.

    abstract::The octavolateralis area of actinopterygian fishes can be subdivided into a dorsal lateralis area composed of first-order lateral line nuclei, and a ventral octavus area composed of nuclei receiving first-order input from the eighth nerve. Three patterns of organization of the lateralis area are recognized in the pres...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1051710205

    authors: McCormick CA

    更新日期:1982-02-01 00:00:00

  • Fine structure and functional morphology of the mouthparts of a male Veigaia sp. (Gamasida: Veigaiidae) with remarks on the spermatodactyl and related sensory structures.

    abstract::Mites of the genus Veigaia are common gamasid inhabitants of forest litter. They engage in the peculiar reproductive strategy of podospermy which, along with other morphological and behavioral adaptations, involves modification of the chelicerae of the relatively rare males into gonopods. Each movable digit is provide...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10393

    authors: Di Palma A,Alberti G,Nuzzaci G,Krantz GW

    更新日期:2006-02-01 00:00:00

  • Morphology of the ovaries of Sphaerodema (Diplonychus) rusticum (Heteroptera, Belostomatidae).

    abstract::The female reproductive system of Sphaerodema rusticum consists of a pair of ovaries, two lateral oviducts, a median common oviduct, and a median spermatheca. Accessory glands are absent. Each ovary has five free ovarioles branching from the oviduct. Each ovariole consists of a terminal filament, germarium, vitellariu...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1052050207

    authors: Jawale SM,Ranade DR

    更新日期:1990-08-01 00:00:00

  • Architectonic constraints on the hyoid's optimal starting position for suction feeding of fish.

    abstract::During suction feeding teleost fish have to start mouth opening prior to other expansion movements of the head such as operculo-suspensorium abduction. The distribution of the input force over the various expansion movements is determined by the position of the hyoid in the expansion apparatus. Based on a three-dimens...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/(SICI)1097-4687(199604)228:1<1::AID-JMOR1>

    authors: De Visser J,Barel CDN

    更新日期:1996-04-01 00:00:00

  • Patterns of fluctuating asymmetry in the limbs of anurans.

    abstract::It has been hypothesized that fluctuating asymmetry (FA) may provide an indication of the functional importance of structures within an organism, with structures that more strongly impact fitness being more symmetric. Based on this idea, we predicted that for tetrapods in which the forelimbs and hindlimbs play an uneq...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.20967

    authors: Didde RD,Rivera G

    更新日期:2019-04-01 00:00:00

  • A new type of somatosensory organ in the nasolabial skin of the dog.

    abstract::A new morphological type of somatosensory organ is described. It is found in the glabrous skin of the dog nose (rhinarium or planum nasale) and situated in dermis papillae. The otherwise thick epidermis forms a thin window above the organ. There are only a few layers of keratinocytes in the window and the corneocytes ...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.21108

    authors: Elofsson R,Kröger RHH

    更新日期:2020-03-01 00:00:00

  • Spermiogenesis in Odontophrynus cultripes (Amphibia, Anura, Leptodactylidae): Ultrastructural and cytochemical studies of proteins using E-PTA.

    abstract::Spermiogenesis in the South American leptodactylid frog Odontophrynus cultripes was analyzed ultrastructurally. The spermatids undergo morphological modification while still enclosed in microtubule-rich processes of Sertoli cells. Electron-dense plates resembling junctional structures appear in regions at which the sp...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1052070307

    authors: Báo SN,Dalton GC,de Oliveira SF

    更新日期:1991-03-01 00:00:00

  • On the allometry of long bones in dogs (Canis familiaris).

    abstract::The allometric relations of diameter and length of humerus, ulna, femur, and tibia of 108 specimens, from 63 different breeds of dogs and 12 specimens of wolves, were calculated by means of model II of regression or major axis method. Only for the tibia were the values of wolves included in the cluster formed for dog ...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.1051900107

    authors: Casinos A,Bou J,Castiella MJ,Viladiu C

    更新日期:1986-10-01 00:00:00

  • Is the large size of the pinna of the ear of the European hare (Lepus europaeus) due to its role in thermoregulation or in anterior capital shock absorption?

    abstract::Large pinnae are characteristic of the Leporids, and the pinna is known to have a thermoregulatory role. Another role has been hypothesized for the pinna of Lepus spp., as a part of a suspensory system for the greater portion of the head, absorbing shock that might otherwise interfere with vision during high-speed loc...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10825

    authors: Stott P,Jennings N,Harris S

    更新日期:2010-06-01 00:00:00

  • Morphology and evolution of the jaw suspension in lamniform sharks.

    abstract::The morphology of the jaw suspension and jaw protrusion mechanism in lamniform sharks is described and mapped onto a cladogram to investigate how changes in jaw suspension and protrusion have evolved. This has revealed that several evolutionary modifications in the musculoskeletal apparatus of the jaws have taken plac...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.10342

    authors: Wilga CD

    更新日期:2005-07-01 00:00:00

  • Morphogenesis and histogenesis during the arm regeneration in a basket star Astrocladus dofleini (Euryalida, Ophiuroidea, Echinodermata).

    abstract::Basket stars, that is, Ophiuroidea in Echinodermata, exhibit distinctive morphological characteristics with their complicatedly branched arms that can regenerate immediately after mutilation. Although, in brittle stars, that is, ophiuroids with nonbranched arms, the arm regeneration process following accidental trauma...

    journal_title:Journal of morphology

    pub_type: 杂志文章

    doi:10.1002/jmor.21296

    authors: Okanishi M,Kohtsuka H,Miura T

    更新日期:2021-02-01 00:00:00