Mesocoeliidae is a common parasite of the small intestine of amphibians and reptiles. From Egypt, only Mesocoelium monas (Rudolphi C., Berolini 811 (1819)) (Freitas JF, Revista Brasiliera de Biologia 18:171-174, (1958)) was reported and described by (Saad AI et. al., J Egypt Ger Soc Zool 33: 219-234, (2000)) from the small intestine of the Egyptian toads Bufo regularis from Aswan Governorate, Upper Egypt, and the molecular characterization of the same parasite was reported by (Mansour MFA et. al., Egypt. J. Biol. (Zool.),10:(1)1-8, (2014)) without any morphological description from the same final host. The present study aimed to detect the prevalence and the characteristic morphological features of mesocoeliid parasites of the Egyptian toads Bufo regularis. Toads were collected from Assiut and Giza Governorates during the autumn of 2018. They were dissected and examined by a dissecting microscope for intestinal parasites. The collected trematodes were fixed, stained, dehydrated, cleared, and mounted. Photomicrographs were taken and parasite measurements were determined. Some of the identified worms were prepared for scanning electron microscope for studying their ultrastructure. Mesocoelium sociale was detected from the small intestine of 14 out of 51 toads Bufo regularis (27.5%) with worm burden (10–30 worms per host). Detailed morphometric characteristic features of the parasite were described by a light microscope. Scanning electron microscopy showed many fine ultrastructure details in the present study and confirmed the light microscopic description. Mesocoelium sociale (Luhe M, Centralblatt fur Bakteriologie Parasitenkunde und Infektionsk-rankheiten, 30, 166-177, (1901)) (Odhner T., Res. Swedish Zool Exped Egypt iv, (23a), 1–166, (1910)) is recorded for the first time from Egypt as a trematode parasite of the Egyptian toads’ Bufo regularis and described by a light microscope. In addition, it is described for the first time worldwide by scanning electron microscopy.

中文翻译：

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第一次光学显微镜和超微结构描述 Mesocoelium sociale (Luhe, 1901) Odhner, 1910 (Trematoda: Mesocoeliidae) in Bufo regularis from埃及

Mesocoeliidae 是一种常见的两栖动物和爬行动物小肠寄生虫。在埃及，只有 Mesocoelium monas (Rudolphi C., Berolini 811 (1819)) (Freitas JF, Revista Brasiliera de Biologia 18:171-174, (1958)) 被 (Saad AI et. al., J Egypt) 报道和描述Ger Soc Zool 33: 219-234, (2000)) 来自上埃及阿斯旺省的埃及蟾蜍 Bufo regularis 的小肠，该寄生虫的分子特征由（Mansour MFA 等人，埃及）报道. J. Biol. (Zool.),10:(1)1-8, (2014)) 没有来自同一最终宿主的任何形态学描述。本研究旨在检测埃及蟾蜍 Bufo regularis 中腔体寄生虫的流行情况和特征形态特征。蟾蜍是在 2018 年秋季从 Assiut 和 Giza 省收集的。它们被解剖并通过解剖显微镜检查肠道寄生虫。收集到的吸虫进行固定、染色、脱水、清除和封固。拍摄显微照片并测定寄生虫测量值。一些已鉴定的蠕虫准备用于扫描电子显微镜以研究它们的超微结构。从 51 只蟾蜍中的 14 只小肠中检测到 Mesocoelium sociale（27.5%），带有蠕虫负担（每个宿主 10-30 只蠕虫）。通过光学显微镜描述了寄生虫的详细形态测量特征。扫描电子显微镜在本研究中显示了许多精细的超微结构细节，并证实了光学显微镜描述。Mesocoelium sociale (Luhe M, Centralblatt fur Bakteriologie Parasitenkunde und Infektionsk-rankheiten, 30, 166-177, (1901)) (Odhner T., Res. Sweden Zool Exped Egypt iv, (23a), 1–166, (1910)) 首次从埃及被记录为埃及蟾蜍的蟾蜍的吸虫寄生虫，并被描述通过光学显微镜。此外，它在世界范围内首次通过扫描电子显微镜进行描述。