The taxon Koinocystididae is the third most species-rich family within Eukalyptorhynchia. However, its diversity and phylogeny have been largely neglected in former studies. We introduce three new genera twelve species of including Simplexcystis asymmetrica gen. n. sp. n., Galapagetula cubensis eight Reinhardorhynchus two Itaipusa. This raises total number from 51 to 63. also report on distribu...

Mating plugs occluding the female gonopore after mating are a widespread phenomenon. In scorpions, two main types of mating plugs are found: sclerotized mating plugs being parts of the spermatophore that break off during mating, and gel-like mating plugs being gelatinous fluids that harden in the female genital tract. In this study, the gel-like mating plug of Euscorpius italicus was investigat...

We describe two new species, Austrognathia glandifera and Austrognatharia orientis using observations on squeezed, live specimens as well as histological sections and transmission electron microscopy. The protonephridia of Austrognatharia orientis are composed of a terminal cell, a canal cell, and a nephroporus cell. The monociliated terminal cell constitutes the so-called filtration area. The ...

Traumatic mating behaviors often bear signatures of sexual conflict and are then typically considered a male strategy to circumvent female choice mechanisms. In an extravagant mating ritual, the hermaphroditic sea slug Siphopteron quadrispinosum pierces the integument of their mating partners with a syringe-like penile stylet that injects prostate fluids. Traumatic injection is followed by the ...

Cement gland protein in male and inseminated female individuals of an acanthocephalan parasite of fish, Pomphorhynchus laevis (Müller, 1776), was localized by immunohistochemistry using an antibody specific for cement protein. Male P. laevis possess 3 pairs of round to oval cement glands ranging from 0.5 to 0.9 mm in length and from 0.3 to 0.7 mm in width. Each gland has an outer portion contai...

Illiosentis Van Cleave et Lincicome, 1939 initially included two species: furcatus found in the West Atlantic from Cape Cod Massachusetts, USA to northern Argentina and cetratus Cleave, 1945 with restricted distribution Pacific coast of southern California. We are reporting I. Peru for first time describe a population California corbina, Menticirrhus undulatus (Girard), The proboscis hook formu...

Osedax is a genus of siboglinid annelids in which the females live on dead vertebrate bones on the seafloor. These females have a posterior end that lies within the bone and contains the ovarian tissue, as well as the "roots" involved with bone degradation and nutrition. The males are microscopic and live as "harems" in the lumen of the gelatinous tube that surrounds the female trunk, well away...

Although mating has been described in several hermit crab species, the mechanics of spermatophore transfer have not previously been demonstrated. Evidence from pleopod and gonopore morphology, video observations, and inseminated females indicates that in Clibanarius vittatus the male applies a spermatophoric mass directly onto the female via the gonopores rather than with modified pleopods 1-2 ...

The patterns of complexity of the male and female sexual openings in Brachyura, which have been the source of uncertainties and conflicting opinions, are documented, together with a study of the morphologies of the coxal and sternal gonopores in both sexes, penises, spermathecae, and gonopods. The vulvae, male gonopores and penises are described among selected taxa of Eubrachyura, and their fun...

While the monophyly of winged insects (Pterygota) is well supported, phylogenetic relationships among the most basal extant pterygote lineages are problematic. Ephemeroptera (mayflies) and Odonata (dragonflies) represent the two most basal extant lineages of winged insects, and determining their relationship with regard to Neoptera (remaining winged insects) is a critical step toward understand...