Lymphomyeloid organs of amphibia. V. Comparative histology in diverse anuran species

Abstract

AbstractEleven different adult anuran species were observed for the presence or absence of the lymphomyeloid complex (LMI‐7). The organs were compared with those of Rana catesbeiana, which were recently studied extensively. Three species (Kassina senegalensis, Bufo boreas and Bufo powerii) did not have any LM organs; six species, i.e., Hypopachus pearsei, Phrynomerus bifasciatus, Rana montezumae, Rana pipiens, Hyla arborea and Bufo marinus, had jugular bodies (LM3); Hyla had also procoracoid bodies (LM7); Bufo marinus had, in addition to LM3 and LM7, another pair that did not have any counterpart to those already reported. The two remaining species possessed entirely different sets of LM organs. Xenopus melleri had large, paired hemal nodes attached to the ventral surface of the laterorostral portion of the hyoid cartilage on either side of the midline and a lymphoid follicle in the neighboring connective tissue. The hemal nodes had a nodular cortex surrounding a nonnodular medulla; no lymphatic sinuses were found inside nor lymphatic vessels associated with these organs. Hemisus marmoratum had paired, small corpora subdermale that were partially overlapped by the depressor mandibulae. These were small, thickly encapsulated, well‐vascularized lymphoid bodies. The organs in the six species were characterized as thinly encapsulated, highly vascularized, non‐nodular lymphatic tissues; some were lymphomyeloid. The LM organs of starved Rana pipiens and Rana montezumae, in contrast to those of well‐fed ones, were smaller and without fat cells. Lymphomyeloid organs of hibernating Rana catesbeiana were no different than those of non‐hibernating frogs.