Reproductive biology of Ophiocoma aethiops and O. alexandri (Echinodermata: Ophiuroidea) from Estacahuite Bay, Oaxaca, Mexico

Benítez‐Villalobos, Francisco; Aguilar-Duarte, Catalina; Avila-Poveda, Omar Hernando

doi:10.3354/ab00467

Cited by 16 publications

(10 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After dissection and gonad extraction, each gonad was cut into several transverse‐sections that were dehydrated in ethanol series, cleared three times in Citrisolv ® , and infiltrated three times and embedded in paraplast ® , following the procedure of Benítez‐Villalobos et al . () and Avila‐Poveda and Abadia‐Chanona (). Serial transverse‐sections were cut at 5‐mm thickness using a manual rotary microtome (LEICA ® RM2145) and mounted on glass slides.…”

Section: Methodsmentioning

confidence: 98%

Observation and establishment of gonad development stages in polyplacophorans (Mollusca): Chiton (Chiton) articulatus a case study

et al. 2016

View full text Add to dashboard Cite

Gonad development stages (GDS) and, subsequently, the reproductive cycle are described by performing histology of some gonad portions. In polyplacophorans, gametogenesis is not enough to define GDS; further anatomical gonad features are relevant. In most adult polyplacophorans, the gonad is a simple anatomical structure that resembles and operates as one single gonadal acinus without glandular structure. These features have gone unnoticed causing inaccurate GDS assignment and, consequently, imprecise reproductive season in polyplacophorans. Here, dissection protocols that allow extracting a compact gonad are established. Emphasizing the anatomical structure of the whole gonad and the displacement of gametes, five GDS were assigned to both sexes of Chiton (Chiton) articulatus: I‐goniogenesis, II‐development, III‐ripe, IV‐spawning, V‐rest. Tissue platelets contribute importantly to GDS assignment and even help distinguishing between males and females. Neither a randomly selected portion of gonad nor a longitudinal section are recommended because it leads to misinterpretation higher than 50% in determining GDS and besides ignores displacement of gametes. A panoramic sweep across a complete transverse‐section of each gonad was validated as the best option for establishing GDS. This new methodology was tested on several polyplacophorans species, and seems generally applicable for histological assessment of reproductive cycle and reproductive season in polyplacophorans.

show abstract

Section: Methodsmentioning

confidence: 98%

Observation and establishment of gonad development stages in polyplacophorans (Mollusca): Chiton (Chiton) articulatus a case study

et al. 2016

View full text Add to dashboard Cite

show abstract

“…2). Each portion was dehydrated in an ethanol series, cleared in Citrisolv®, and infiltrated and embedded in paraffin [50]–[51]. Serial sections were cut at 5-µm thickness using a manual rotary microtome (LEICA® RM2145) and mounted on glass slides.…”

Section: Methodsmentioning

confidence: 99%

Emergence, Development, and Maturity of the Gonad of Two Species of Chitons “Sea Cockroach” (Mollusca: Polyplacophora) through the Early Life Stages

Avila-Poveda¹,

Abadia-Chanona²

2013

PLoS ONE

View full text Add to dashboard Cite

This study describes and recognises, using histological and microscopical examinations on a morphometrical basis, several gonad traits through the early life stages of Chiton articulatus and C. albolineatus. Gonadal ontogenesis, gonad development stages, sexual differentiation, onset of the first sexual maturity, and growth sequences or “early life stages” were determined. In addition, allometry between lengths and body weight pooled for both sexes per each chiton were calculated using equation Y = aXb. A total of 125 chitons (4≤TL≤40 mm, in total length “TL”) were used. All allometric relations showed a strong positive correlation (r), close to 1, with b-values above three, indicating an isometric growth. Gonadal ontogenesis and gonad development stages were categorised into three periods (“Pw” without gonad, “Pe” gonad emergence, and “Pf” gonadal sac formed) and four stages (“S0” gametocytogenesis, “S1” gametogenesis, “S2” mature, and “S3” spawning), respectively. Compound digital images were attained for each process. Periods and stages are overlapped among them and between species, with the following overall confidence intervals in TL: Pw 6.13–14.32 mm, Pe 10.32–16.93 mm, Pf 12.99–25.01 mm, S0 16.08–24.34 mm (females) and 19.51–26.60 mm (males), S1 27.15–35.63 mm (females) and 23.45–32.27 mm (males), S2 24.48–40.24 mm (females) and 25.45–32.87 mm (males). Sexual differentiation (in S0) of both chitons occurs first as a female then as a male; although, males reach the onset of the first sexual maturity earlier than females, thus for C. articulatus males at 17 mm and females at 32 mm, and for C. albolineatus males at 23.5 mm and females at 28 mm, all in TL. Four early life stages (i.e., subjuvenile, juvenile, subadult, and adult) are described and proposed to distinguish growth sequences. Our results may be useful to diverse disciplines, from developmental biology to fisheries management.

show abstract

“…For example, both sexes of some animals can exhibit GSI in excess of 40% during the reproductive season (e.g. the broadcast spawning brittle star Ophiocoma alexandri , Benítez‐Villalobos, Aguilar‐Duarte & Avila‐Poveda, ), yet in many others male GSI falls well below 1% (e.g. 0.02% in the gorilla, Gorilla gorilla , Kenagy & Trombulak, ).…”

Section: Introductionmentioning

confidence: 99%

The evolution of expenditure on testes

Parker

2016

Journal of Zoology

View full text Add to dashboard Cite

Evolutionary theory for expenditure on gonads attracted little attention until studies in the past 3-4 decades of allocation to male and female function in hermaphrodites, and of relative testes size (RTS) in animals with separate sexes. RTS appears to have varied enormously over evolutionary time, from extremely high (over 40%) in some broadcast spawners to less than 1% in some taxa with copulation and internal fertilization. Reasons for this wide evolutionary diversity in testes expenditure deserve attention. Sperm demand (the product of expenditure per ejaculate and mating rate) increases expenditure on testes, and is moulded by a number of selective forces: sperm competition, mating rate and sperm limitation are identified as the three typically most powerful. Trade-offs between somatic and testes expenditures can be complex, particularly those between pre-and post-copulatory expenditure. Theoretical models predict that RTS should correlate positively with sperm demand, and there is much evidence from many taxa that RTS increases with sperm competition level. The relation between RTS and expenditure on each ejaculate is predicted to be positive over low sperm competition (risk) levels, and negative over high (intensity) sperm competition levels. Sexual cascade logic suggests that gonad expenditure should be high and equal for the two sexes soon after the early evolution of anisogamy, but should diverge widely through evolutionary time, with RTS reducing notably in those taxa that have evolved advanced mobility and internal fertilization.

show abstract

Reproductive biology of Ophiocoma aethiops and O. alexandri (Echinodermata: Ophiuroidea) from Estacahuite Bay, Oaxaca, Mexico

Cited by 16 publications

References 28 publications

Observation and establishment of gonad development stages in polyplacophorans (Mollusca): Chiton (Chiton) articulatus a case study

Observation and establishment of gonad development stages in polyplacophorans (Mollusca): Chiton (Chiton) articulatus a case study

Emergence, Development, and Maturity of the Gonad of Two Species of Chitons “Sea Cockroach” (Mollusca: Polyplacophora) through the Early Life Stages

The evolution of expenditure on testes

Contact Info

Product

Resources

About