to the braincase, jaws, and skeletal elements of the mouth (teeth). For this purpose, prehatching ontogenetic cranial series of these two caiman species were prepared with a double staining and diaphanization technique. to grow until the organism has reached full adult size. undifferentiated tooth structure, Turbinate bones - bones of the nasal
The columella auris (Fig. (B) Left lateral view of the palatoquadrate of CL232. plural splanchnocraniums or splanchnocrania -n-. The embryos are left in KOH solution until the material is totally cleared and the view of cartilages and bones is ideal. Between the middle anterior end and each anterior lateral process, there is a notch that begins to develop in CY19 and CL222 (Fig. (B) Dorsal view of cricoid cartilage of CY253. In lateral view, this region extends from the posterior area of the postconcha to the prootic fenestra. The middle anterior end of the Corpus hyoidei also exhibits fingerlike projections, as described for the anterior lateral processes. Comp Biochem Physiol C Toxicol Pharmacol. Following, the visceral arches of the splanchnocranium and the trachea are described. Between the trabeculae and a posterior transverse bar of cartilage, the crista sellaris, the triangular hypophysial fenestra is delimited. The tracheal rings are open dorsally and are placed immediately behind the cricoid cartilage without contacting it (Fig. (B) Dorsolateral view of the orbitotemporal region of CY17/181. than homogenous materials. 1897. Present only in teleostomi splanchnocranium lie in spaces called lacunae (Fig. Supporting this idea, Di Pietro etal. Werneburg & Yaryhin (2018) have pointed out that some structures of this region (i.e. This paper deals with the cartilaginous cranium only; bones will be discussed in another scientific article. visceral skeleton: When describing the characteristics
They begin to develop in stage 22 of C. latirostris (observed only in CL2210 and CL2211 of this stage) and in stage 23 of C.yacare (except CY231, CY23 3, CY234). The identification, spatial relationships, and sequences of development of the cartilaginous and bony elements of the chondrocranium, osteocranium, and splanchnocranium in the medaka, Oryzias latipes, are described here for the first time. found in lungfishes, and in the tetrapod ancestors, Axis - the second cervical vertebra
These projections have not yet appeared in CL20, CL21, CL221, CY17/181, CY17/182, CY17/183, CY181, CY182, CY19; its development begins in CL222 and CY20 (Fig. This region extends from the pila antotica to the occipital condyle and comprises the auditory capsules, the basal plate and the tectum synoticum. CL2210, CL2211, CY239, CY2312, CY2313), the medial projections merge with the lateral ones (Fig. Stages 1719 in C. latirostris and final stages of C.yacare (stages 2628) could not be sampled due to nonavailability of material but this did not affect this study. He also proposed that the hypobranchial 1 and 2 would contribute to the posterior area of the middle anterior process and the basibranchial 1 and 2 would contribute to the Corpus hyoidei itself. anterior surface, concave on posterior surface, characteristic of some
12B). vision, which results in reinforcement of the eyeball with a ring of bones
The dorsal cartilaginous portion of the hyoid arch is associated with the auditory capsule and is represented by a system of continuous cartilages arranged behind the otic notch. The neurocranium consists of three different regions, which are described below. that are part of the body, remain strong under the stresses of locomotion, such as when the
Beneath it, the only occipital condyle develops, which is a posterior continuation of the basal plate and surrounds the notochord. In the ventral view of this region is the lamina transversalis anterior, which forms the floor of the anterior middle portion of each capsule and occupies a larger space as development progresses (Figs1B and and2B).2B). Dorsal (A) and ventral (B) views of CY221; right lateral view (C) of CL224. eCollection 2015 Feb 1. 10A). Unlike the three foramina that Klembara (1991) described in Alligator, the maximum number of hypoglossal foramina observed in this work was four (or probably five, see Results), which would likely indicate that at least four occipital arches were incorporated in this region. Squalus. These include the ease of obtaining embryos for which the exact time of fertilization is known (without sacrificing any brood stock) and the relatively rapid development of the chondrocranium, which is nearly complete at hatching, a process which can occur in as short a time as 6 days (at 34C). jaws, ears and parts of the hyoid apparatus and pharyngeal cartilage (Fig. Although its maximum width is in the anterior part and decreases progressively towards the posterior region, the plate undergoes a sharp narrowing in the area of contact with the Cornu branchiale I (Fig. um splak-n-kr-n-m. In most terrestrial vertebrates, including mammals (e.g., the cat and humans), the chondrocranium The incorporation of earlier embryonic stages would be useful to discern the homologies of the hyobranchial apparatus and the basitrabecular and infrapolar processes that remained undiscovered in this work. In the public domain. Moreover, this author identified the free end of the Cornu branchiale I as an epibranchial. -encase the chondrocranium and splanchnocranium-contributes to brain case, jaws, and skeletal elements of the mouth (teeth) . government site. 8A). The amplitude of the fenestra means that the zona annularis is not as well developed in C. latirostris and C.yacare as in other species of crocodylians (De Beer, 1937; Bellairs & Kamal, 1981). Dorsally, each parietotectal cartilage is vaulted and the medial junction between them establishes a groove. is shown in Table 7.2 (p. 228) - LEARN THIS, The dermatocranium is composed of plates
The variation found in this study is useful to give us an idea about the phylogenetic constraints, and they could be studied in a heterochronic context in comparison with other crocodylian species. The facialis nerve passes by this foramen (Klembara, 1991). Together with the pharyngeal skeleton, it comprises the cranial endoskeleton (endocranium). Hu Y, Willett KL, Khan IA, Scheffler BE, Dasmahapatra AK. 2013; SalasGismondi etal. the tissues that will go into the construction of skeletal elements. However, no studies have analyzed the chondrocranium of any species of caiman. The largest, most dorsal and lateral, is the epioptic fenestra. only of Meckels cartilage - encased in exoskeletal bone of the
2009 May;84(2):315-46. doi: 10.1111/j.1469-185X.2009.00077.x. There is an internal order within each ontogenetic series in which the name of the species is first written and abbreviated (CY=C.yacare; CL=C.latirostris), followed by the stage number and the number of specimen within each stage for each species. of the brain as well as the ear and nose, during development, cartilage forms
BMC Genomics. Would you like email updates of new search results? of the vertebrae of reptiles and mammals, Perichondrium - the connective tissue
condition is heterodont, where teeth are modified for different
The
from the external nares to the lungs, Chondrocranium - anterior part of the
(2012), SalasGismondi R, Flynn J, Baby P, etal. membrane, as well as articular cartilages that help to maintain the fluid
Dorsal view of Meckel's cartilage (A) and ventral view of palatoquadrate (C) of CY20. selection favoring fish that utilized the first visceral arch to help it
2015 Feb 27;16(1):135. doi: 10.1186/s12864-015-1325-7. 2B). Photographs were obtained using a Nikon D40 camera. the eye, Splanchnocranium - or visceral arches
The cartilaginous elements partially ossify via endochondral differentiation; much of the chondrocranium is ossified as neurocranium in adults and . The chondrocranium is the large single element of the head skeleton (Figure 3.2 ). The concha nasalis occupies a part of the fenestra basalis, partially dividing it into two portions, an anterior one and a more elongated and wider posterior one (Figs1A,B and and22AC). Iordansky NN (1973) The skull of the Crocodilia In: The cranial anatomy of early ontogenetic stages of, The parasphenoid and associated dermal structures of the parabasisphenoid of, Postparietal and prehatching ontogeny of the supraoccipital in, Ontogeny of the partial secondary wall of the otoccipital region of the endocranium in prehatching, Lafortune M, Gbel T, Jacobson E, etal. This last statement could not be corroborated in this study since they were always observed as separate elements. 4). (2016). Clipboard, Search History, and several other advanced features are temporarily unavailable. Found primarily on the ends of ribs and on
Some of these characters could be distinctive of Caiman, its two extant species or even Alligatoridae. Epub 2006 Mar 20. the jaws in gnathostomes. amphibians, Pygostyle - the fused caudal vertebrae
and transmitted securely. Conclusions: The difference in SPARC expression during chondrogenesis of the splanchnocranium is likely based on its different evolutionary history compared with the dermatocranium and chondrocranium. found in the vertebrae of cartilaginous fish, bone consists of calcium phosphate and other organic salts deposited
2010). the skeletal elements encasing the brain. Lateral and posterior views of Squalus chondrocranium. These differences could become apomorphies of each species. Parker, 1882; Shiino, 1914; De Beer, 1937) as well as external morphology (e.g. Moreover, our results suggest a co-occurrence of the initial calcium deposition and bone matrix protein expression during osteogenesis. Prehatching ontogenetic cranial series of C. latirostris and C.yacare were studied. In general terms, the cartilaginous neurocrania of C. latirostris and C.yacare are very similar to each other and to that of other crocodylian species. Stage 26 was not described in C.latirostris because of the noneruption of teeth in this species (exclusive attribute of this stage). The aditus conchae shows in its most dorsal portion a foramen that would be considered the epiphanial foramen (see Discussion), which serves as the exit of the ramus lateralis nasi of the profundus branch of the trigeminal nerve (V1; see De Beer, 1937: 229). The remaining bones of the skull are dermal in origin. (2015), A Miocene hyperdiverse crocodylian community reveals peculiar trophic dynamics in protoAmazonian megawetlands, SalasGismondi R, Flynn J, Baby P, etal. From stage 24 in C.yacare and from stage 23 in C.latirostris these free ends show a tongueshaped growth that extends medially until reaching the midline at the end of the development, leading to the dorsal closure of the cricoid (Fig. Dorsal (A) and ventral (B) views of CL20, CY17/181 and CY19; right lateral view of CY17/181 and CY19 (C). An official website of the United States government. 10C). is an elaborate cartilagenous case around the brain. 3C). tissue whose matrix contains proteoglycan molecules that bind with water. be deposited in one of two ways: formation of membrane bone begins with the formation of trabeculae
are supported solely by the hyomandibular; found in elasmobranchs and most
In dorsal views of most specimens of early stages of C.yacare (n=6, stages 17/18, 19, 20 and 22), the optic and epioptic fenestrae reach the same level of anterior extension. the neurocranium and covers the ventral, lateral and posterior parts
This video is part of Zoo 430: Comparative Anatomy of the Vertebrates. Before 1988;177(4):297-305. doi: 10.1007/BF00315836. create a pump-like action, jaw formation probably evolved from
of the mandible and meet the prearticular and coronoids, - left and right mandibles usually
Fibrocartilage - cartilage containing
Two general parts of the skeleton are the: General function of the skull and
9B). up the dermatocranium (Table 7.3 and Fig. from gills to lungs - requires the evolution of a pair of internal nostrils,
Parker, 1882; Meek, 1911; Shiino, 1914; Goldby, 1925; De Beer, 1937). In conclusion, all the abovementioned hypotheses of homology of the hyobranchial apparatus are equally likely and none deserves more support than other (Table2). and layers of bone matric surrounding a central canal through which nervess
CY17/181). and quadrate (suspends the lower jaw); replaced by maxilla
and blood and lymphatic vessels travel. Basibranchial Cartilage 10. hyomandibular, Autostylic (lungfishes and in
(2016). Subsequently, at the level of its free posterior area, it forms another smaller notch in the two species. Cornu branchiale I would correspond to ceratobranchial I according to Parker (1882), De Beer (1937), Romer (1956), Schumacher (1973), Bellairs & Kamal (1981) and Klembara (1991). In CY182, the chondrocranium begins to align and this angle disappears completely in CY19, CY20 and CL20. anterior and posterior end, characteristic of teleosts and early reptiles, Amphistylic - jaw is supported both
that extend forward and backward of neural arches and help to strengthen
Found in the intervertebral disks and pubic symphysis, Fontanelle - temporary gaps between
Federal government websites often end in .gov or .mil. The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). intervertebral disks and pubic symphysis, Calcified cartilage - cartilage containing deposited calcium salts;
The palatoquadrate is composed of two branches, a dorsal branch (otic process) and a ventral one (articular portion sensu De Beer, 1937). Dynamic expression of sparc precedes formation of skeletal elements in the Medaka (Oryzias latipes). or sternum for attachment of breast muscles, Sacrum - the union of two or more vertebrae
The majority of taxonomical diagnoses are principally based on morphological traits of skulls and mandibles (e.g. Dorsal view of CL224 of the orbitotemporal (C) and oticoccipital (D) regions. The lateral wall of the capsule is dorsal and posteriorly contoured by the crista parotica (Figs1A,C and and2A,C).2A,C). A few individuals of C.latirostris (CL20, CL222, CL223 and CL232) have a medium and anterior foramen (Fig. hide this ad PLAY QUIZ Score 0/17 Timer 10:00 Recently Published The postconcha is visible as a bulge lateral to the lateral fenestra and posterior to the concha nasalis. Renn J, Schaedel M, Volff JN, Goerlich R, Schartl M, Winkler C. Gene. 10B) and, as a result, the posterior lateral processes have a different degree of development in each species (Fig. arranged fibers, and some elasticity, nuchal ligaments, for example, are prominent in animals with large
Its ventral area, which rests on the Corpus hyoidei, is flat and expanded. However, only three bones remain in the chondrocranium (exoccipital, opisthotic, and prootic) and one in the visceral arches (quadrate). Rostrum 4. gills, 2. A total of 37 embryos of C. latirostris and 34 of C.yacare were used. The neurocranium is a specialised portion of the splanchnocranium and comes from neural crest cells. Shift in gas exchange mechanism
PMC On each side of the middle anterior end of the Corpus hyoidei, there is a lateral and anterior process, flat and lobular, whose anterior border is irregular due to the existence of fingerlike projections (Fig. Between the auditory capsule and the basal plate, the fissura metotica opens, an axially elongated opening located below the area where the capsule joins the basal plate, just lateral, dorsal and anterior to the hypoglossal foramina (Figs1C, C,2C,2C, C,44 and and5).5). ( vis'r--kr'n-m ), [TA] That part of the cranium derived from the embryonic pharyngeal arches; comprises the facial bones of the facial skeleton (under bone) and is distinct from that part of the cranium that forms the neurocranium (braincase). In those cases, Klembara (1991) was followed. (2011), Light microscopic and immunohistochemical study of the trachea of the broadsnouted caiman (, Historiae Amphibiorun Naturalis et Literariae. In its path, it develops a medial and ventral curvature, its free anterior end terminating in a structure similar to a condyle. size ratios, requiring increased braincase size, - birds have modification of the jaws
From stage 24 on, they are already present in all embryos of both species. head shield formed from a single piece of of arched dermal bone, two close-set
: the portion of the skull that arises from the first three branchial arches and forms the supporting structure of the jaws. (2008), who developed a criterion for aging embryos of C.latirostris using external morphological features. - birds tend to have larger brain-to-body
I would like to express my gratitude to the people of Estancia El Cachap, in Chaco province, who collaborated with the field trips. In crocodylians, this cartilage system is composed of the columella auris, whose medial portion ossifies and whose lateral portion (extracolumella) remains cartilaginous. the nasal cavity, - the prefrontals, postfrontals, and
appq, articular portion of the palatoquadrate; ch, Corpus hyoidei; on, otic notch; oppq, otic process of the palatoquadrate; pppq, pterygoid process of palatoquadrate. cupola anterior, alar process, pars parietotectalis and pars paranasalis) were not described by that author in crocodylians. 10C). Chondrocranium of Caiman latirostris (MLPR.6491) and Caimanyacare (MLPR.6490). visceral arches composed of cartilage or cartilage replacement bone, generally seven visceral arches grow
National Library of Medicine 10A). A separate epibranchial associated with the Cornu branchiale I has not been distinguished either. (2016). Based on Thomas DB et al. CC BY-NC 4.0. The posthatching ontogenetic shift in the proportions and relative position of the articular fossa and the retroarticular process, and the ecological and biomechanical implications will be evaluated in a future morphofunctional study of the mandible. Biol Rev Camb Philos Soc. The scoop-like rostrum projects anteriorly and contains the precerebral cavity. across the floor acted as a suctioning device to pull water into the mouth
The basitrabecular process, according to De Beer (1937), is a lateral projection of the most posterior portion of the trabecular bar and is formed of the polar cartilage, when the latter element chondrifies independently. As the skull plays a fundamental role in systematic phylogenetic analysis of Crocodylia, investigating its development and morphological change over the time, especially in embryonic stages, is absolutely necessary. Six basic groups of dermal bones make
Columella auris of Caiman latirostris (MLPR.6491) and Caimanyacare (MLPR.6490). 1897. Afterwards, each specimen is conserved in glycerol. On the other hand, Cleuren & De Vree (1992) claim that the Cornua branchialia II have been fused or lost. eCollection 2022. 10A,B). heads and/or long necks, - lowering the neck to the ground, in contrast, requires muscular
primitive condition of teeth is homodont thecodont, which
The main differences between C.yacare and C.latirostris, and other crocodylian species were recorded in the splanchnocranium. The first two are considered part of the Cranial Skeleton. 2C) and its presence differs from that in other crocodylian species because, although it is present in Alligator mississippiensis (Klembara, 1991) and Caiman crocodilus (Witmer, 1995), it does not appear in the genus Crocodylus (De Beer, 1937; Bellairs & Kamal, 1981; Klembara, 1991).