11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 26: Biodiversity and Diversification of Reef Organisms
26.1206
Octocoral Abundance And Diversity Associated To Eastern Pacific Rocky Reefs
(Colombia)
Nestor ARDILA* 1 , Johana PARRA 1 , Dairo ESCOBAR 1 , Nelson MANRIQUE 1 , Juan
SANCHEZ 1
1 Ciencias Biológicas, Universidad de los Andes, Bogota, Colombia
Octocorals assemblage patterns and spatial distributions were studied from the
Colombian eastern Pacific covering ten sites in a range of water depths (3-17 m) in order
to evaluate different diversity measures at Gorgona island (Montañita I y II, Farallones,
Juanchincho y el Horno) and Cabo corrientes (La Roñosa, Punta Arusi, Punta Diego, El
chuzudo, Parguera). A total of 25 species were quantified using belt quadrants
(50x50cm). Pacifigorgia spp. afforded the greatest number of species (>10 species),
followed by Leptogorgia spp. (four species), Muricea spp. (three species) and the rest of
genera with only one species: Eugorgia, Heterogorgia and Carijoa. Carijoa riisei, an
invasive species from the Caribbean, was locally very abundant at a few stations both
continental and oceanic areas. In terms of abundance, L. alba was the best represented
(40 %). Octocoral densities were highly variable (2 - 30 colonies m-2) and showed
evidence of a relationship to a bathymetric gradient. Alpha diversity was highly variable
(1-8 species) and La Roñosa, Montañita II and Juanchincho were the localities with
higher diversity and densities. The community structure showed the dominance of
Pacifigorgia cf. symbiotica in shallow waters and L. alba in deeper waters. Muricea
fruticosa was exclusive to Cabo corrientes and has been recorded in other expeditions
from continental rocky reefs in Puerto Lopez, Ecuador, but was absent in Gorgona island.
Finally, L. alba was the only species spanning the entire sampling area and depths.
26.1207
Does Vertical Symbiont Transmission Always Lead To A ‘closed’ Association?
Symbiont Diversity Of Parents, Planulae And Recruits Of The Brooding Caribbean
Coral Porites Astreoides
Mary Alice COFFROTH* 1 , Lyndsey HOLLAND 1 , Cynthia LEWIS 2
1 Geology, University at Buffalo, Buffalo, NY, 2 FWC/FWRI, Marathon, FL
The symbiosis between reef building corals and dinoflagellates in the genus
Symbiodinium is the basis for the massive structures that dominate coral reefs. Coral
offspring acquire their algal symbionts either vertically from the maternal colony or
horizontally from the surrounding environment. In species with horizontal transmission,
new recruits can initially harbor a range of symbiont types which revert to the adult
assemblage over time. In vertical acquisition, it is assumed that maternal symbionts are
passed to the larvae and that the maternal symbiont type is the only one found within the
newly settled recruit. However, this has not actually been demonstrated. Using variation
in chloroplast large subunit (23S) ribosomal DNA , we compared symbiont types within
maternal colonies, larvae, newly settled recruits and year old juveniles from the
Caribbean scleractinian Porites astreoides, a brooding coral that transmits its symbionts
vertically. In the majority of cases, the offspring do indeed harbor solely the symbiont
type of the maternal colony. However, in some cases the offspring harbor additional
Symbiodinium types that are not the dominant type found in the maternal colonies. This
suggests that either exogenous symbionts are acquired following planulae release or that
cryptic Symbiodinium spp. within the maternal colony are passed to the developing
larvae.
26.1208
Multiple Ecological Radiations Of Sea Cucumbers Onto Coral Reefs
Alexander KERR* 1 , Ronald CLOUSE 2 , Mark O’LOUGHLIN 3 , Tim O'HARA 3 , Daniel
JANIES 4
1 Marine Laboratory, University of Guam, Mangilao, Guam, 2 Museum of Comparative Zoology,
Harvard University, Cambridge, MA, 3 Marine Biology Section, Museum Victoria, Melbourne,
Australia, 4 Department of Biomedical Informatics, Ohio State University, Columbus, OH
Aspidochirotida is a large order of sea cucumbers (ca. 25% of extant diversity) consisting of
three families: Synallactidae, Stichopodidae and Holothuriidae. Most members are either found
on coral reefs or at great depth. We present a phylogeny of 45 species of aspidochirote
holothuroids (13% of ordinal-level diversity) based on PCR-amplified partial 16S, 12S, 28S,
18S and H3 gene sequences. Estimated maximum likelihood and maximum parsimony
topologies, the latter estimated via POY direct optimisations, indicated that Synallactidae is
polyphyletic and renders Stichopodidae paraphyletic. This jumble suggests that members of the
former family experienced at least two parallel losses of planktotrophic larvae and complicates
interpretations of the bathymetric diversification within the aspidochirotes. The third family,
Holothuriidae, appears monophyletic and consists of two large basal subclades. Surprisingly,
several previously unconsidered gross anatomical and ecological characters define these groups.
The first subclade, “Holothuriinae,” is primarily of cylindrical, diurnally cryptic to burrowing
forms, while the second subclade “Bohadschiinae,” consists mostly of large, diurnal and
epibenthic species with flattened ventrums. Further, bohadshiines often release a fluorescent
green exudate when first placed in alcohol. These obvious characters permit straightforward
diagnosis of two large clades in a family with a tumultuous nomenclatural history.
26.1209
Structure Of Coral Reef Fish Communities Associated With Massive And Branching
Corals At Gorgona Island, Tropical Eastern Pacific
Julio C. BENÍTEZ* 1 , Santiago CUEVAS 1 , Alan GIRALDO 1 , Fernando A. ZAPATA 1
1 Department of Biology, Universidad del Valle, Cali, Colombia
The reef fish communities of two coralline microhabitats in the Tropical Eastern Pacific are
described. A total of 447 individuals of 35 species of fish in 16 families were sampled in
massive and branching colonies using a box-mesh of 1m3 and clove oil as anesthetic.
Cirrhitichthys oxycephalus (34.9 %) and Pseudogramma thaumasium (15.7 %) were the most
abundant species, whereas the remaining species were rare. Massive colonies had a more
diverse fish community (mean Shannon H'= 1.36 ± 0.36 SD) than branching colonies (H'= 1.14
± 0.33 SD). Correlation analyses indicated that topographic complexity was not related to any
structural parameter of the community (total abundance, richness, Shannon diversity (H') or
evenness). H’ increased with increasing available volume only among branching colonies.
Colony isolation (distance to nearest coral) showed a positive relation with total abundance,
species richness, and H’ only for branching colonies. Cluster analyses based on occurrence and
abundance of the 12 most abundant species did not indicate the existence of a distinctive
assemblage structure on either coral microhabitat. Apogon dovii was the only species whose
mean total length differed between microhabitats, with larger sizes in branching (57.5 mm ±
13.0 SD) than in massive colonies (35.3 mm ± 19.4 SD). Although branching corals had more
available space within colonies than massive corals, the latter had more species per unit volume.
However, abundance was more equitably distributed in massive corals. In spite of obvious
differences in coral morphology, the total richness and species composition of the fish
communities did not differ markedly between the two microhabitats.
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