Abd-Elhafeez Hanan H, Massoud Diaa, Mahmoud Mohammed S, Abdellah Nada, Salah Abdallah S, Mohamed Nor-Elhoda, Sayed Mennatallah Ali Abdelrhman, Shaalan Mohamed, Rutland Catrin S, Abu-ELhamed Alaa Sayed, Soliman Soha A, Mustafa Fatma El-Zahraa A
Department of Cell and Tissues, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt.
Department of Biology, College of Science, Jouf University, Sakaka, Saudi Arabia.
Int J Vet Sci Med. 2024 Sep 4;12(1):101-124. doi: 10.1080/23144599.2024.2374201. eCollection 2024.
Studying scute and fin morphology are advantageous approaches for phylogenetic identification and provide information on biological linkages and evolutionary history that are essential for deciphering the fossil record. Despite this, no prior research has precisely characterized the histological structures of scutes in the common pleco. Therefore, this research investigated the microstructure and organization of bone tissue within the dermal skeleton, including the scutes and fins, in the common pleco, using light microscopy, stereomicroscopy, and scanning electron microscopy. The dermal scutes were organized in a pentagonal shape with denticular coverage and were obliquely aligned with the caudal portion pointing dorsally. The dermal scutes consisted of three distinct portions: the central, preterminal, and terminal portions. Each portion comprised three layers: a superficial bony plate, a basal bony plate, and a mid-plate. Both the superficial and basal bony plates were composed of lamellar bone and lamellar zonal bone, whilst the mid-plate consisted of secondary osteons and woven bone. In the terminal portion, the superficial and basal bony plates became thinner. The pectoral fin consists of spines and rays composed of lepidotrichium (two symmetrical hemi-rays). The spine contained centrifugal and centripetal lamellar and trabecular bones. A centripetal fibrous bone was implanted between the lamellar bones. Besides being oriented in a V shape, the hemi-rays were also composed of thin centrifugal and centripetal lamellar bones and trabecular bones. A fibrous bone was identified between the centrifugal and centripetal bones. The trabecular bone and lamellar bone were made up of bone spicules.
研究盾鳞和鳍的形态是系统发育鉴定的有利方法，并能提供有关生物联系和进化历史的信息，这些信息对于解读化石记录至关重要。尽管如此，此前尚无研究精确描述过普通鲶鱼盾鳞的组织结构。因此，本研究利用光学显微镜、体视显微镜和扫描电子显微镜，对普通鲶鱼真皮骨骼内的骨组织微观结构和组织进行了研究，包括盾鳞和鳍。真皮盾鳞呈五边形排列，有锯齿状覆盖，且与尾部倾斜对齐，尾部指向背侧。真皮盾鳞由三个不同部分组成：中央部分、终端前部分和终端部分。每个部分由三层组成：表层骨板、基底骨板和中间板。表层和基底骨板均由板层骨和板层带状骨组成，而中间板由二级骨单位和编织骨组成。在终端部分，表层和基底骨板变薄。胸鳍由由鳞质鳍条（两条对称的半鳍条）组成的鳍棘和鳍条组成。鳍棘包含离心和向心的板层骨和小梁骨。在板层骨之间植入了向心纤维骨。除了呈V形排列外，半鳍条还由薄的离心和向心板层骨以及小梁骨组成。在离心骨和向心骨之间发现了纤维骨。小梁骨和板层骨由骨针组成。
