Sexual Reproduction in Mycetophyllia Genus Presentation

Sexual Reproduction in Sexual Reproduction in the Caribbeanthe Caribbean Coral Genus Coral Genus Mycetophyllia Mycetophyllia inin

La Parguera La Parguera , , Puerto RicoPuerto Rico .. byby

José A. José A. MMoralesorales Department of Marine Department of Marine

Sciences RUMSciences RUM

M. feroxM. feroxM. danaanaM. danaana

M. aliciaeM. aliciae

IntroductiIntroductioonn:: • Corals show a wide variety of reproductive strategies.Corals show a wide variety of reproductive strategies.• AsexualAsexual::

-- BuddingBudding –– Polyp fission to allow the growth of colony. Polyp fission to allow the growth of colony.

-- FragmentationFragmentation- Establish new colonies of higher sizes.- Establish new colonies of higher sizes.

-- Polyp bail outPolyp bail out andand Polyp ballsPolyp balls- For dispersion under - For dispersion under unfavorable conditions. unfavorable conditions.

-- Asexual larvaeAsexual larvae – For wider dispersion – For wider dispersion - GemaeGemae and and Tissue sloughingTissue sloughing – For dispersion near of parental – For dispersion near of parental

colony.colony.

•• Asexual strategies Asexual strategies do not produce genetic variabilitydo not produce genetic variability, , advantagesadvantages include include higher rate of reproductionhigher rate of reproduction and the and the bypass of mortalitybypass of mortality associate with embryos developmental stages in the water associate with embryos developmental stages in the water column.column.

IntroductiIntroductioonn::

• Sexual:Sexual:

--GonochGonochoricoric or or HermaphroditeHermaphrodite

BroodersBrooders- high survivorship and low dispersal - high survivorship and low dispersal

capability.capability.

SpawnersSpawners- high mortality and high dispersal capability.- high mortality and high dispersal capability.

•• The final The final advantage of sexual strategiesadvantage of sexual strategies is to produce is to produce offspring with offspring with different genotypesdifferent genotypes, increasing the , increasing the genetic variabilitygenetic variability of the population. of the population.

IntroductiIntroductioonn ::

• For the combination of these strategies For the combination of these strategies ::- Colonies are potentially immortal - no - Colonies are potentially immortal - no

senescence at the colony level.senescence at the colony level.- High genetic variability – sexual reproduction - High genetic variability – sexual reproduction

across different generations across different generations - Fecundity increases with size and last through - Fecundity increases with size and last through

the life of the colony.the life of the colony.- High survivorship through mass-extinction - High survivorship through mass-extinction

events.events.- High morphological variability- High morphological variability

Justification:Justification:

• Reproductive studies in the Indopacific and Caribbean Reproductive studies in the Indopacific and Caribbean regions revealed differences in coral reproductive regions revealed differences in coral reproductive strategies.strategies.

• In Indopacific region Hermaphroditism and spawning In Indopacific region Hermaphroditism and spawning of gametes are the major strategies.of gametes are the major strategies.

• In the Caribbean Hermaphroditism and brooding In the Caribbean Hermaphroditism and brooding seems to be the major strategies.seems to be the major strategies.


• Knowledge of coral reproductive biology and the Knowledge of coral reproductive biology and the associated processes of dispersion and recruitment is an associated processes of dispersion and recruitment is an essential prerequisite for ecological studies of coral essential prerequisite for ecological studies of coral populations, communities and their dynamics (Harrison populations, communities and their dynamics (Harrison and Wallace, 1990). and Wallace, 1990).

• Little is known about the reproductive patterns and Little is known about the reproductive patterns and characteristic of most coral species in the Caribbean, and characteristic of most coral species in the Caribbean, and most of the information available is usually incomplete or most of the information available is usually incomplete or conflictive (Vargas 2002).conflictive (Vargas 2002).


• The genus The genus MycetophylliaMycetophyllia is a reef builder found only in the is a reef builder found only in the Caribbean.Caribbean.

• There is no information available for the gametogenic There is no information available for the gametogenic cycle of the other four species in this genus (cycle of the other four species in this genus (M. aliciae, M. M. aliciae, M. danaana, M. lamarckiana danaana, M. lamarckiana andand M. reesi M. reesi))..

• There is also lack of information on the fecundity and its There is also lack of information on the fecundity and its variability within and across variability within and across Mycetophyllia Mycetophyllia speciesspecies..

• There are 65-75 coral species in the caribbean and the There are 65-75 coral species in the caribbean and the reproductive biology has been described for 22 species.reproductive biology has been described for 22 species.

ObjectivesObjectives ::

• To To characterize the reproductive patternscharacterize the reproductive patterns (hermaphroditic (hermaphroditic or gonochoric) or gonochoric) and mode of developmentand mode of development (brooder or (brooder or spawner) of the species of spawner) of the species of MycetophylliaMycetophyllia common in Puerto common in Puerto Rico. Rico.

• To To characterize the gametogenetic cyclescharacterize the gametogenetic cycles and the and the distribution of gametesdistribution of gametes in the mesenteries. in the mesenteries.

• Determine timing and frequency of Determine timing and frequency of brooding eventsbrooding events • To To assess fecundityassess fecundity per mesentery and polyp. per mesentery and polyp. • To To assess variability in sexual reproductionassess variability in sexual reproduction among the among the

four common species in Puerto Rico.four common species in Puerto Rico.

Null and alternative Null and alternative hypotheses:hypotheses:

• H01: There are no differences in the H01: There are no differences in the mode of mode of developmentdevelopment among the among the Mycetophyllia Mycetophyllia species.species.• H11: At least one species shows a different mode ofH11: At least one species shows a different mode of development.development.

• H02: There are no differences in the H02: There are no differences in the sexual patternsexual pattern among among the four species of the four species of Mycetophyllia.Mycetophyllia.• H12: At least one species shows a different sexual pattern.H12: At least one species shows a different sexual pattern.

Null and alternative Null and alternative hypotheses:hypotheses:

• H03: There are no differences in the H03: There are no differences in the timing oftiming of

gametogenesisgametogenesis among the species. among the species.• H13: At least one species shows differences in the H13: At least one species shows differences in the

timing of gametogenetic cycle.timing of gametogenetic cycle.• H04: There are no differences in H04: There are no differences in fecundityfecundity among the among the

Mycetophyllia Mycetophyllia species.species.• H14: At least one species has significatively different H14: At least one species has significatively different

fecundity level.fecundity level.

Species of Species of Mycetophyllia Mycetophyllia in Puerto Rico.in Puerto Rico.

M.ferox M.ferox (Wells, 1973)(Wells, 1973) M. aliciae M. aliciae (Wells, 1973)(Wells, 1973)

M. Lamarckiana M. Lamarckiana (Edward and Haime, 1848)(Edward and Haime, 1848)

M. DanaanaM. Danaana(Edward and Haime, 1848)(Edward and Haime, 1848)

Materials & Methods:Materials & Methods:

Figure 6: Figure 6: Reefs sampled in La PargueraReefs sampled in La Parguera


Figure 7.Figure 7. Sampling collection. Sampling collection.


Figure 8:Figure 8: Procedure for sample preparation for histological sections. Procedure for sample preparation for histological sections.

Table 1.Table 1. Criteria for classification of gametocytes and embryos into Criteria for classification of gametocytes and embryos into developmental stages following Szmant-Froehlich et al. (1985).developmental stages following Szmant-Froehlich et al. (1985).

Simultaneous hermaphrodites:Simultaneous hermaphrodites:

Fig. 9: Fig. 9: Tissue sections of four species of Tissue sections of four species of Mycetophyllia Mycetophyllia (A-D in 4x) showing different (A-D in 4x) showing different stages of oocytes (O) and spermatocytes (S). Mature stages: IV in oocytes and V in stages of oocytes (O) and spermatocytes (S). Mature stages: IV in oocytes and V in spermatocytes.spermatocytes.

Simultaneous hermaphroditesSimultaneous hermaphrodites ::

• Hermaphroditism is a conservative feature of sexual Hermaphroditism is a conservative feature of sexual reproduction in corals, which have a phylogenetic basis reproduction in corals, which have a phylogenetic basis (Harrison, 1985). (Harrison, 1985).

• It has been proposed to be the ancestral condition It has been proposed to be the ancestral condition (Szmant, 1986), with gonochorism as a derived (Szmant, 1986), with gonochorism as a derived character.character.

Gamete arrangement:Gamete arrangement:

Figure 10. Figure 10. Female mesentery, A- Male mesentery, B- Female mesentery, A- Male mesentery, B- SyngonicSyngonic mesentery, mesentery, C- and C- and DigonicDigonic mesentery, D. mesentery, D.

Brooders:Brooders:

Figure 11: Figure 11: Tissue sections of four species of Tissue sections of four species of Mycetophyllia Mycetophyllia (A-D in 4x) (A-D in 4x) showing internal development of larvaes.showing internal development of larvaes.

Brooders:Brooders:

• Szmant, (1986) proposed that brooding evolved in coral Szmant, (1986) proposed that brooding evolved in coral species occupying unstable habitats and subject to high species occupying unstable habitats and subject to high rates of adult mortality.rates of adult mortality.

• Advantages of being a brooder include bypassing all Advantages of being a brooder include bypassing all

risks of high gamete and larvae mortality associated risks of high gamete and larvae mortality associated with developmental stages in the water column with developmental stages in the water column (Szmant, 1986).(Szmant, 1986).

Figure 12Figure 12. Gamete and Embryo characteristics in . Gamete and Embryo characteristics in M. ferox.M. ferox.

A. Spermaries development

B. Oocytes development

C. Larvae development

Figure 13:Figure 13:Proportion of colonies with Proportion of colonies with gametes andgametes andembryos in each stage of embryos in each stage of gametogenesis and gametogenesis and embryogenesis,by embryogenesis,by month, during years month, during years 2000-01 in 2000-01 in M. ferox.M. ferox.

Gametogenesis Gametogenesis and and

embryogenesisembryogenesis

Figure 14Figure 14. Gamete and Embryo characteristics in . Gamete and Embryo characteristics in M. aliciae.M. aliciae.


B. Oocyte development


Figure 15:Figure 15:Proportion of colonies Proportion of colonies with gametes and embryos in with gametes and embryos in each stage of gametogenesis and each stage of gametogenesis and embryogenesis, by embryogenesis, by month, during years month, during years 2000-01 in 2000-01 in M. aliciaeM. aliciae..



Figure 16Figure 16. Gamete and Embryo characteristics in . Gamete and Embryo characteristics in M. lamarckiana.M. lamarckiana.




Figure 17:Figure 17:Proportion of colonies with Proportion of colonies with gametes and embryos in each gametes and embryos in each stage of gametogenesis and stage of gametogenesis and embryogenesis, by month, during embryogenesis, by month, during years 2000-01 in years 2000-01 in M. lamarckliana.M. lamarckliana.



Figure 18Figure 18. Gamete and Embryo characteristics in . Gamete and Embryo characteristics in M. danaana.M. danaana.




Figure 19:Figure 19:Proportion of colonies with Proportion of colonies with gametes and embryos in each gametes and embryos in each stage of gametogenesis and stage of gametogenesis and embryogenesis,by embryogenesis,by month, during years month, during years 2000-01 in 2000-01 in M. danaana.M. danaana.



Gametogenesis and embryogenesis:Gametogenesis and embryogenesis:

• Differences in the arrangement of gametes and Differences in the arrangement of gametes and timing of maturation suggest that besides cross-timing of maturation suggest that besides cross-fertilization. Also these species may reproduce fertilization. Also these species may reproduce by self-fertilization under particular conditions. by self-fertilization under particular conditions.

Figure 20: Figure 20: Box-plot for mesenterial and Box-plot for mesenterial and polyp fecundity among polyp fecundity among Mycetophyllia Mycetophyllia species.species.

Different capital letters indicate Different capital letters indicate significant differences (p significant differences (p < < 0.0001).0.0001).

Fecundity:Fecundity:

Fecundity:Fecundity:

• Differences in mesenterial and polyp fecundity were Differences in mesenterial and polyp fecundity were tested with a non parametric one-way ANOVA test tested with a non parametric one-way ANOVA test (Kruskal Wallis) because (Kruskal Wallis) because data failed the normality test data failed the normality test and variances were not equal (p < 0.050). and variances were not equal (p < 0.050).

• Kruskal Wallis revealed: significative differences by Kruskal Wallis revealed: significative differences by stage (I-IV) in the average diameter of oocytes in each stage (I-IV) in the average diameter of oocytes in each species and no significative difference among larvae in species and no significative difference among larvae in stage IV of stage IV of M. ferox, M. danaana M. ferox, M. danaana and Mand M. lamarckiana. lamarckiana

Figure 21:Figure 21: Puerto Rico Sea Surface Temperature Time Series Puerto Rico Sea Surface Temperature Time Series Charts - Pathfinder, NOAA/NASA AVHRR Oceans SST (SST = Charts - Pathfinder, NOAA/NASA AVHRR Oceans SST (SST = Sea Surface Temperature).Sea Surface Temperature).

GametogenesisGametogenesisM.M.

danaanadanaanaGametogenesisGametogenesis

M. feroxM. feroxM. aliciaeM. aliciae

GametogenesisGametogenesisM.M.

lamarckianalamarckiana

EmbryogenesisEmbryogenesisM. feroxM. ferox

EmbryogenesisEmbryogenesisM. danaanaM. danaana

EmbryogenesisEmbryogenesisM. aliciaeM. aliciae

EmbryogenesisEmbryogenesisM.M.

lamarckianalamarckiana

Figure 22:Figure 22:Sun & Moon light period in Sun & Moon light period in hours during year 2000-01.hours during year 2000-01. Y axis: time period in hours Y axis: time period in hours for sunlight and moonlight. for sunlight and moonlight. X axis shows the dates of X axis shows the dates of sampling and the onset of sampling and the onset of oogenesis and oogenesis and embryogenesis for the embryogenesis for the species in different colors. species in different colors.

Results andResults and Discussion:Discussion:

Table 2. Table 2. Summary of gametogenetic timing and reproductiveSummary of gametogenetic timing and reproductive characteristicscharacteristics..

Results and Discussion:Results and Discussion:

• Porites astreoides Porites astreoides had 9 reproductive cycles per year (Szmant, had 9 reproductive cycles per year (Szmant, 1986), with regular intervals in phase with the lunar cycle and 1986), with regular intervals in phase with the lunar cycle and high recruitment.high recruitment.

• Favia fragum Favia fragum had 12 reproductive cycles per year (Szmant-had 12 reproductive cycles per year (Szmant-Froelich, 1985), with regular intervals in phase with the lunar Froelich, 1985), with regular intervals in phase with the lunar cycle and high recruitment.cycle and high recruitment.

• All spawning spp have one reproductive cycle per year All spawning spp have one reproductive cycle per year (Vargas, 2002) with one-two spawning events synchronized (Vargas, 2002) with one-two spawning events synchronized with moon phases.with moon phases.

Results and Discussion:Results and Discussion:

• Mycetophyllia feroxMycetophyllia ferox like like P. poritesP. porites brooded during brooded during winter. winter.

• Mycetophyllia aliciae Mycetophyllia aliciae andand M. lamarckiana M. lamarckiana brooded brooded during spring likeduring spring like Agaricia agaricites Agaricia agaricites, , A. crassaA. crassa and and Isophyllia Isophyllia sp.sp.

• Mycetophyllia danaana Mycetophyllia danaana brooded year around like brooded year around like A. A. humilis, F. fragum,humilis, F. fragum, Manicina areolata, P. astreoides Manicina areolata, P. astreoides and and Siderastrea radians. Siderastrea radians.

ConclusionsConclusions :: • All fourAll four Mycetophyllia Mycetophyllia species are simultaneous-hermaphrodites that species are simultaneous-hermaphrodites that

brood larvae.brood larvae. • All four species showed different timing and duration in their All four species showed different timing and duration in their

gametogenesis and embryogenesis, a possible mechanism to prevent gametogenesis and embryogenesis, a possible mechanism to prevent hybridization. hybridization.

• Gamete arrangement was similar in all species, with both syngonic Gamete arrangement was similar in all species, with both syngonic and digonic patterns.and digonic patterns.

• The four species had only one gametogenetic cycle a year but brood The four species had only one gametogenetic cycle a year but brood larvae during extended periods (several months). larvae during extended periods (several months).

• M. aliciaeM. aliciae had significantly higher mesenterial fecundity and might had significantly higher mesenterial fecundity and might liberate larvae in early stages (L-II), which could enhance the liberate larvae in early stages (L-II), which could enhance the dispersion distances.dispersion distances.

ConclusionsConclusions :: • M. feroxM. ferox showed the lowest mesenterial fecundity but, showed the lowest mesenterial fecundity but,

produced the most developed larvae, competent to settle produced the most developed larvae, competent to settle down shortly after leaving the parental colony. This is the down shortly after leaving the parental colony. This is the most abundant of all most abundant of all MycetophylliaMycetophyllia species. species.

• M. lamarckianaM. lamarckiana and and M. danaanaM. danaana had intermediate had intermediate fecundities and larvae in stage IV are less developed than fecundities and larvae in stage IV are less developed than M. ferox.M. ferox. Both species have lower abundances than Both species have lower abundances than M. M. feroxferox and and M. aliciaeM. aliciae..

• There is a potential for self-fertilization in all species; There is a potential for self-fertilization in all species; Further genetic analyses of the larvae should be done.Further genetic analyses of the larvae should be done.

ACKNOWLEDGEMENACKNOWLEDGEMENTS:TS:

• Department of Marine Sciences, UPR, Sea Grant College Department of Marine Sciences, UPR, Sea Grant College Program, Chemistry Department, NOAA-CRES Project. Program, Chemistry Department, NOAA-CRES Project.

• Dr. Ernesto WeilDr. Ernesto Weil• Isabel UrreiztietaIsabel Urreiztieta• Dr. Nilda AponteDr. Nilda Aponte• Moisés R. MarcanoMoisés R. Marcano• Luisa TiradoLuisa Tirado• Héctor MoralesHéctor Morales

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Sexual Reproduction in Mycetophyllia Genus Presentation