How Can I Mate Without An Appendix Masculina? The Case of Sphaeroma Terebrans Bate, 1866 (isopoda, Sphaeromatidae)

Messana, G.

doi:10.1163/1568540041643346

Cited by 8 publications

(5 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This phenomenon has also been noted by Messana (2004) in Sphaeroma terebrans Bate, 1866. It is very difficult to observe mating in Dynamene due to the cryptic habitat of the adults.…”

Section: Resultssupporting

confidence: 66%

Distribution and species identification in the crustacean isopod genus Dynamene Leach, 1814 along the North East Atlantic-Black Sea axis

Vieira¹,

Queiroga²,

Costa³

et al. 2016

View full text Add to dashboard Cite

Sphaeromatid isopods, such as Dynamene, are common and abundant members of the invertebrate fauna of littoral and shallow sublittoral substrates. Six species of Dynamene occur in the northern hemisphere. Only two species exist outside this range, in Australia. The distribution of the various species in the NE Atlantic-Black Sea axis has been controversial due to the difficulty in the identification of the different species. This has led to inaccurate records of their distribution, ultimately generating uncertain or faulty assessments on the biodiversity of these habitats. An update and a clarification about the distribution of this genus is therefore in order. In this study, we describe the distribution of Dynamene species in the light of new records from the NE Atlantic Ocean and its associated islands, and the Mediterranean, Black and Red Seas, and from re-examination of museum and several authors’ personal collections. Based on these observations, we extend the northern and southern limits of Dynamene bidentata (Adams); the western and southern limits of Dynamene magnitorata Holdich; the northern, eastern and western limits of Dynamene edwardsi (Lucas); and the eastern and western limits of Dynamene bifida Torelli. The range of Dynamene tubicauda Holdich is extended, but is still only known from the eastern Mediterranean. We also clarify the synonymy of Dynamene torelliae Holdich with Dynamene bicolor (Rathke), and the occurrence of Dynamene bicolor in the Black Sea. New distribution maps of the six Dynamene species are presented. Illustrated keys to the adult males and females of the northern hemisphere species are provided.

show abstract

“…This phenomenon has also been noted by Messana (2004) in Sphaeroma terebrans Bate, 1866. It is very difficult to observe mating in Dynamene due to the cryptic habitat of the adults.…”

Section: Resultssupporting

confidence: 66%

Distribution and species identification in the crustacean isopod genus Dynamene Leach, 1814 along the North East Atlantic-Black Sea axis

Vieira¹,

Queiroga²,

Costa³

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Histological examination of the female gonopore may confirm the presence of sperm prior to oviposition. The absence of the appendix masculina is uncommon in isopods and has only been reported in Sphaeroma terebrans , in which fertilisation occurs after the male releases sperm into a water current generated by the female pleopod (Messana, 2004).…”

Section: Discussionmentioning

confidence: 99%

Reproductive behaviour of the branchial ectoparasite Bopyrus crangorum (Isopoda: Bopyridae) following ecdysis of the host Palaemon serrifer (Caridea: Palaemonidae)

Burgos,

Itani

2023

J. Mar. Biol. Ass.

View full text Add to dashboard Cite

The reproduction of bopyrid isopod parasites is thought to occur immediately following host ecdysis, but direct observations supporting this hypothesis are limited. The aim of this study was to describe the reproductive behaviour of the bopyrid isopod Bopyrus crangorum relative to host ecdysis based on video recordings. Several hours after host ecdysis, biphasic moulting of female parasites was observed. The cuticle of the posterior body was shed before that of the anterior body at an interval of 1 h. Two hours after female moulting, the male repeatedly moved from its initial position between the female pleopods and stopped at the anterior end of the fifth oostegite, immediately above the gonopore. To our knowledge, this repeated visiting behaviour by males has not been previously observed in bopyrid isopods. Oviposition through the female gonopore occurred 33 min later. The male-removal experiment showed that females with their males removed after visits to the gonopore oviposited eggs, whereas females with their males removed before visits did not. We propose that repeated visits by males to the gonopore are attempts to inseminate the female. We hypothesised that sperm are released onto the external surface of each gonopore and that the eggs are fertilised as they pass through the opening, which would explain the synchronous development of fertilised eggs inside the marsupium. The present study provides new information on the life history of bopyrid isopods, which allows for a better understanding of the host–parasite relationship.

show abstract

“…The isopod Sphaeroma sieboldii Dollfus, 1889 is found inhabiting rocky shores burrowing in wood or sandstone. It has been reported to lack the appendix masculina, which is attached to the endopod of the second pleopod (Shiino 1957) and serves as a male secondary sex characteristic that is used to transfer sperm to the female (Messana 2004). The lack of appendix masculinae is rare in isopods, but has occasionally been reported in Sphaeroma species, including S. terebrans (Venkata Krishnan and Nair 1973a), S. sieboldii, S. retrolaevis (Shiino 1957) and S.…”

Section: Introductionmentioning

confidence: 99%

“…wadai (Murata and Wada 2002). Messana (2004) has reported the mating behaviour of S. terebrans, in which the male releases sperm into the water current created by the beating of the female s pleopods.…”

Section: Introductionmentioning

confidence: 99%

Life history of an intertidal boring isopod, <i>Sphaeroma</i> <i>sieboldii</i> Dollfus, 1889

Kitaura

Nunomura

2019

Crust Res

View full text Add to dashboard Cite

Population structure, growth and reproductive activities were investigated over one year for the boring isopod Sphaeroma sieboldii Dollfus, 1889 for a population burrowing in sandstone. The occurrence of heterosexual pairs peaked in spring, followed by the peak occurrence of ovigerous females and females cohabiting with early juveniles in the summer. This suggests the reproductive season is from spring to summer. For adult males that had penes, three reproductive stages were recognized: large-sized males with mature appendices masculinae, intermediate-sized males with immature appendices masculinae, and small-sized male without appendices masculinae. Most of the males pairing with females were large-sized males with mature appendices masculinae, while most of the pairing females were smaller than the partners, carrying small, non-functional oostegites. Males with mature appendices masculinae were frequent from winter to summer, covering the reproductive season. Size-assortative pairing was found in the peak season of heterosexual coupling. Sex ratios were female-biased in all months. Observation of the interior reproductive organs confirmed that adult females had ovaries, while most males had both ovaries and male reproductive tracts. Some males with mature appendices masculinae were found to have degenerated ovaries. These findings suggest that protogynous sex change occurs in S. sieboldii.

show abstract

How Can I Mate Without An Appendix Masculina? The Case of Sphaeroma Terebrans Bate, 1866 (isopoda, Sphaeromatidae)

Cited by 8 publications

References 11 publications

Distribution and species identification in the crustacean isopod genus Dynamene Leach, 1814 along the North East Atlantic-Black Sea axis

Distribution and species identification in the crustacean isopod genus Dynamene Leach, 1814 along the North East Atlantic-Black Sea axis

Reproductive behaviour of the branchial ectoparasite Bopyrus crangorum (Isopoda: Bopyridae) following ecdysis of the host Palaemon serrifer (Caridea: Palaemonidae)

Life history of an intertidal boring isopod, <i>Sphaeroma</i> <i>sieboldii</i> Dollfus, 1889

Contact Info

Product

Resources

About