Figure - available from: Canadian Journal of Zoology
This content is subject to copyright. Terms and conditions apply.
(a) Drawing of a neck quill. The stippled part is the pitted region. The short tip to the right is not pitted. Arrow points to the anchoring end. (b) Side view of the developing pitted fibrillous cuticular cell (PFCC) at early and late stages in the thin-spined porcupine (Chaetomys subspinosus). In the early stage, raised cuticular scales of the inner root sheath (IRS) insert in grooves between the raised quill cuticular scales as per the “early surface view”. In the late stage, the soft cuticular scales swell to surround the cuticular scales of the IRS as per the “late surface view”. A cuticular cell of the hair (Cx) in Fig. 1f corresponds to the whole PFCC in Fig. 1b; the cuticle of the IRS (Ci) in Fig. 1e corresponds to the cuticle of the IRS in top left of Fig. 1b. (c) A view of the PFCC from above and to the side to show the quill’s cuticular cortical scales before swelling. The scales tilt at 65° to the shaft. The PFCC is basically a hexagonal or pentagonal prism. (d) Late stage after swelling: (above) the IRS cuticle is simple squamous with several spatulate, slanted, raised scales; (below) an IRS cuticular cell with three scales, two of which have been cut to show their cross-sectional profiles. Distal to right. (e) Details of the differentiated PFCC. The cuticular scales of the IRS are inserted in pits. One IRS scale has a segment removed to reveal the pit’s walls. Later the scales of the IRS disintegrate resulting in empty pits. This sheath makes imprints on the quill surface. Only one imprint is shown. At a pit’s base is the opening of the circumferential tunnel (T) connecting other pits (PIT); the ∼12 μm thick pitted layer showing fusion (F) of the scales; the ∼10 μm thick fibrillous layer (Fb). The fibrils are radial at the pit’s bottom, but deeper in they extend horizontally in different directions. The fibrils become more compacted basally. The large black dots represent melanosomes. Distal to right. (f) Stereogram of a developing human hair follicle, which is the same as in an Erethizon quill’s follicle. The cuticle (Cx) of the hair’s cortex starts off as a single layer of hexagonal prismatic cells (but cuboid in section), then the cells flatten, tilt, keratinize, and die, but are retained. The cuticle of the IRS (Ci) interlocks with the cuticle of the cortex (Cx). CT, connective tissue; Hn, Henle’s layer; Hx, Huxley’s layer; *, degeneration of the scales of the IRS; ORS, outer root sheath
Source publication
Scanning electron microscopy shows that the quill surface from the thin-spined porcupine (Chaetomys subspinosus (Olfers, 1818)) has several regional cuticular patterns of which the most expansive is highly pitted with 4 μm wide pores leading to pits, which in turn communicate circumferentially via tunnels to neighboring pits. The cell unit of the p...
Similar publications
Objective
To investigate the efficacy of indirubin combined with human umbilical cord mesenchymal stem cells (hUC-MSCs) in the treatment of psoriatic lesions in BALB/c mice and to explore the related mechanism of indirubin in the treatment of psoriasis.
Methods
A BALB/c mouse psoriasis model induced by imiquimod was established and randomly divide...
Most extant vertebrates display a high variety of tooth and tooth‐like organs (odontodes) that vary in shape, position over the body and nature of composing tissues. The development of these structures is known to involve similar genetic cascades and teeth and odontodes are believed to share a common evolutionary history. Gene expression patterns h...
All living jawed vertebrates possess teeth or did so ancestrally. Integumental surface also includes the cornea. Conversely, no other anatomical feature differentiates the clades so readily as skin appendages do, multicellular glands in amphibians, hair follicle/gland complexes in mammals, feathers in birds, and the different types of scales. Tooth...
Glyptosaurine lizards (Glyptosaurinae, Anguidae) are an extinct group of heavily armored lizards known from North America, Europe and Asia. Glyptosaurine lizards, taxa that possess fully developed tuberculated dermal armor, appear to have been established in North America by late early Puercan time (To3). “Proxestops,” a taxon distinguished by a co...
In this paper, we studied the problem of localizing a generic set of keypoints across multiple quadruped or four-legged animal species from images. Due to the lack of large scale animal keypoint dataset with ground truth annotations, we developed a novel dataset, AwA Pose, for keypoint detection of quadruped animals from images. Our dataset contain...
Citations
... Also described are nine cuticular regions along the quill of Chaetomys. Chapman et al. (2019) described complicated pitted fibrillar cuticular cells (PFCC) on a major extent of the quill. That communication may be referred to concerning fuller details of this porcupine's anatomy, geographical distribution, taxonomy, and behavior. ...
... Skin and quills at low magnification A sketch of a neck quill as well as photos of four regional quills from Chaetomys are depicted in Chapman et al. (2019). A sketch of a single quill is shown in Fig. 1h. ...
... Dane and Herman's (1963) technique with phloxine B and orange G was used as these authors claim it distinguishes soft prekeratin (orange) from harder keratin (red). Chapman et al. (2019) have shown by energy dispersive Xray spectrometry and Fourier transform infrared spectrometry and scanning electron microscopy that the PFCC is kerati-nous and that it has surface pits leading to deeper circumferential tunnels with a separate even deeper layer containing keratinous fibrils. The two layers are separated by a thin keratinous partition. ...
This study examines the functional histology of the thin-spined porcupine's (Chaetomys subspinosus (Olfers, 1818)) quills and integument, and compares them with the North American porcupine (Erethizon dorsatum (Linnaeus, 1758)) equivalents. Erethizon quills disseminate warnings to potential predators. An olfactory warning is generated by sebaceous glands of the lower back, disseminated by osmetrichial specializations of lower-back quills. Chaetomys skin lacks functional sebaceous glands, and generates no warning odor. Erethizon quills also carry a visual warning, effective even in dim light. Chaetomys quills carry no warning color. The straight, stiff quills of Erethizon are tipped with one-way barbs and can be elevated to 90°. A protective collagenous spool at the base of the quill prevents back-stabbing on impact. Chaetomys quills lack barbs and the basal collagenous spool is poorly developed. The quill shafts are wavy and angled at the base, allowing them to act as shock absorbers during a fall from a tree. Nevertheless, Chaetomys quills of the head and shoulders can be elevated to 90° to function as stabbing devices. Major defensive quills of Erethizon protect the back; in Chaetomys, the front. Though both species have 1–3 arrector muscles, they differ in the details of quill stabilization. The Chaetomys quill surface has regional cuticular patterns, of which the distal, longest region is highly pitted. The function of the pitted region remains a mystery.
... The pelage of Coendou may include both quills and hairs, which can partially or completely cover the quills. The quills of Coendou are long, straight or slightly curving and in some parts of the body, like the rump, the spines are defensive with recurved barbs (quills with a unique shape, wavy or kinked, and barbless in the broomstraw-spined porcupine-Voss 2015; Barthelmess 2016;Chapman et al. 2019). The pinna in Coendou and the broomstrawspined porcupine is reduced to an angular ridge of almost naked skin (small but distinct and densely furred in the North American porcupine-Voss 2015). ...
Coendou vestitus Thomas, 1899, a rodent commonly known as the brown hairy dwarf porcupine, is one of the smallest Neotropical porcupines; its body is covered by three different types of hair and a short tail. C. vestitus is endemic to the western foothills of the Eastern Cordillera (Cordillera Oriental) of the Andes region of Colombia, where it has been confirmed through museum voucher specimens from only six localities characterized by lower montane moist forest vegetation. Globally, C. vestitus is listed as “Data Deficient” (DD) by the International Union for Conservation of Nature (IUCN); however, in Colombia it is categorized as “Vulnerable” (VU) by the Minister of Environment and Sustainable Development.
New World porcupines (Erethizontidae) exhibit behaviors and possess integumentary structures, including the quills, that are used for self‐defense. The North American porcupine ( Erethizon dorsatum ) has been well studied regarding these features; however, information is lacking for the South American Coendou species. We describe the defensive behavior and integumentary morphology of Coendou spinosus to understand the defensive strategies of this species and to compare with those reported for other species. We assessed the behaviors related to warning, defense, and escape of eight porcupines, as well as the characteristics of their pelage and quills. Furthermore, we microscopically analyzed skin samples of a roadkill adult male specimen. Similar to E. dorsatum , C. spinosus exhibited omnidirectional quill erection, revealing an aposematic color and, with their backs toward the perceived human threat, they performed quick tail and body movements to strike the hands of the human trying to capture them by the tail. Furthermore, C. spinosus presented an integumentary structure similar to that of E. dorsatum , and mechanisms to facilitate quill release when touched, penetration, and fixation in the opponent. The most distinct warning behavior noted was the vibration of the quills, which has not been reported for Erethizon . Our study confirms that, like other erethizontids, C. spinosus does not attack but exhibits warning, defense, and escape mechanisms and behaviors when threatened or touched. The dissemination of such information helps to counter the negative stigma associated with porcupines, as they can be the victims of attacks by dogs and humans, and to promote their conservation.
