Comparative gonadal histology reveals complex reproductive traits in Cubozoa (Cnidaria: Medusozoa) – Frontiers –

New Lab Publication, Led by Dr. Jimena Garcia-Rodriguez

Cubozoa, a relatively small class within Medusozoa (Cnidaria), is distinguished by its complex sexual behaviors, setting it apart from other medusozoan classes. However, reproductive traits and seasonality remain poorly characterized for many species, largely due to difficulties in obtaining specimens. In this comparative histological study we describe the reproductive tissues (gonads) of males and females at multiple maturity stages across 15 cubozoan species, representing two orders, seven families, and eight genera. We document several reproductive traits: (1) variation in oocyte shape, including polygonal oocytes; (2) unidentified cytoplasmic inclusions within oocytes suggestive of undescribed component of vitellogenesis; (3) swollen gonadal structures in mature males, hinting at an uncharacterized spawning mechanism; and (4) a diverse repertoire of nematocysts within gonadal tissues, including putative nematoblasts in species of both cubozoan orders, indicating distinct developmental pathways for these organelles. Ancestral state reconstruction of three reproductive characters, viz. oocytes with unidentified cytoplasmic inclusions, the presence of nematocysts in gonads, and fertilization mode, suggests that all but the latter likely evolved independently within Cubozoa. By uncovering and characterizing these novel sexual traits in cubozoan jellyfishes, this study provides fundamental baseline data for comparative analyses aimed at elucidating the diversity and evolution of reproductive strategies across medusozoan taxa and their roles in spawning aggregations, also known as jellyfish blooms.

Access the full publication here

Leave a Reply

Your email address will not be published. Required fields are marked *