Polyclad Flatworm Diversity of the Wider CaribbeanD. M. Bolaños 1*, S. Y. Quiroga 1*, K. A. Rawlinson2, M. K. Litvaitis 11 Department of Zoology, University of New Hampshire, Durham, New Hampshire, USA2 MSN Post-doctoral Fellow, Smithsonian Marine Station, Fort Pierce, Florida, USA* Link Fellow, Smithsonian Marine Station, Fort Pierce, Florida, USA

Five new species and a new combination of Cotylea

Methods

• Polyclads were collected from all coastal habitat types accessible byshore work, snorkelling and SCUBA, from the intertidal to a maximumof 15 m.

• Quantitative sampling at 62 sites (characterised by habitat type) in 7locations (excluding Colombia) was undertaken. At most sites two ormore replicated samples were taken. Each sample represented 1 hourof continuous collecting.

• Specimens were preserved [modified after 5] for histology or wholemounts. Individuals were identified to the lowest possible taxonomiclevel (typically species) using light microscopy (species descriptionsand classifications [4, 6, 7]).

• Identifications of new species of Pseudoceros, Pseudobiceros, andMaritigrella were based on the descriptions of color and color patternsand grouped accordingly [8, 9]. Information from the male reproductivesystem, was used for the determination of Thysanozoon.

• Type material has been deposited at the US Natural History Museum(USNM), Washington D.C. and the VIIS collection at the BiosphereReserve Center on St. John, USVI.

• Ecological data analysis software: species accumulation curves -ECOSIM [10], multivariate analysis (ANOSIM, MDS, SIMPER) –PRIMER 5 [11].

Purple-brownish background blending intoblack towards the margin. Dorsal surfacewith large orange and smaller yellow dotsoutlined by a black shadow. Numerous,small white spots along the margin aroundthe entire body. Light purple-violet ventralsurface, more translucent towards themargin. Externally, two male gonoporesare evident, one on either side of theposterior end of the pharynx.

Pseudobiceros pardalis n. comb.

Background transparent brown, darkermedially; raised line over the main intestinewith irregular patches lacking brownpigment. Instead, numerous and denselyconcentrated white dots are substituting thepigment. Dorsal surface covered with darkbrown and white dots irregularly scattered.Larger white spots unevenly distributedaround the margin. Intestinal branchesvisible through the skin as yellow net-likeramifications.

Pseudobiceros caribbensis n. sp. Pseudoceros rawlinsonae n. sp.

Body white, with a black, broad,branched stripe middorsally; thin, brightorange line surrounds the entire body.Tentacles entirely black; no evidence ofwhite body color or orange line on thetentacles. Fusiform, elongated seminalvesicle drained by an ejaculatory duct;ejaculatory duct loops dorsal overprostatic vesicle and enters penispapilla anterior to the prostatic vesicle.

Pseudoceros harrisi n. sp.

Transparent cream-pinkish background.Middle area of dorsal surface with astrong red coloration but absenttowards the margin. Big white spotsover the red pigment. Smaller andnumerous white dots forming aconspicuous margin. Bright whitetentacles.

Translucent brown-blackish backgroundwith numerous large bulbous yellowpapillae over the entire dorsal surface.Small white slash-like marks, hardlyvisible, around the entire margin,sometimes giving the impression of anextremely thin white border. Darkerpigment medially and darker blacktentacles outlined by the white marks.Translucent white ventrally.

Thysanozoon raphaeli n. sp.

White background with brown pigmentarranged in dense, anastomosing, scale-like outlines. Three to five conspicuousand continuous transverse black stripes.Series of finer, grayish-black, transversestripes located between the fiveconspicuous stripes and extending fromthe margins towards the midline of theanimal but not completely crossing thedorsal surface. Narrow, orange, marginalline surrounding the body Tentacles blackwith white tips and white coloration of theanterior margin between the tentacles.

Maritigrella newmanae n. sp.

Figure 1. The geographic distribution of the sampling regions inthe wider Caribbean.Belize (BEL) (South Water Caye), Honduras (HON) (CayosCochinos), Panama (PAN) (Bocas del Toro), Florida Keys (FLO)(Long Key), Jamaica (JAM) (St. Ann’s Bay), Colombia (COL)(Santa Marta),Curaçao (CUR), United States Virgin Islands (USVI)(St. John)

AcknowledgementsWe thank Joseph Dunn, Anne DuPont and Marcin Liana for help with collecting specimens andRaphael Ritson-Williams for providing us with the type specimen and the image of Thysanozoonraphaeli in its habitat This work was supported by NSF grant DEB-0412932.

Literature Cited[1] see refs in Newman & Cannon, 2003. CSIRO Publishing, Melbourne, Victoria, 112 pp[2] see refs in Quiroga et al. 2004. Zootaxa 633: 1–12[3] Bolaños et al. 2007. Zootaxa, 1650: 1-23[4] Prudhoe, 1985. Oxford University Press.[5] Newman & Cannon, 1995. Hydrobiologia 305: 141-143[6] Faubel, 1983. Mitt Hamb zool Mus Inst 80: 17 - 121[7] Faubel,1984. Mitt Hamb zool Mus Inst 80: 189 – 259[8] Newman & Cannon, 1994. Mem Queensland Mus 37: 205 - 266[9] Newman & Cannon, 2000. J Nat Hist 34: 191–205[10] Colwell, 2005. <purl.oclc.org/estimates>[11] Clarke & Gorley, 2001.Plymouth: PRIMER-E

Introduction Flatworms of the order Polycladida (Platyhelminthes) are mobile predators and possibly represent animportant functional component of hard substrate marine environments globally. Little is known about the spatialdistribution of this taxon, but as predators their distribution is probably dependent on prey availability as well as abioticfactors. Higher species richness is found in the tropics, where polyclads are prominent and often colorful members ofcoral reef communities. Due to a long-term sampling effort, some of the highest diversities of polyclads have beenrecorded from the Great Barrier Reef and the Indo-Pacific [1]. In contrast, polyclad diversity in the Caribbean hasreceived much less attention [2, 3], although a distinct fauna had been noted [4]. To corroborate and up-date pastliterature and to provide a first quantitative estimation of polyclad species richness, distribution and assemblagedifferences, a survey of the wider Caribbean was carried out between March 2004 and September 2006 spanning anarea of 15º latitude and 24º longitude (Fig.1).Aims: 1) To carry out a taxonomic inventory of the region.

2) To determine patterns of alpha, beta and gamma species richness. 3) To examine if suites of species form distinct clusters according to habitat or region under multivariate analysis.

Diversity77 taxa belonging to 28 genera and 17 families were recorded from the 8 coastal regions,including 5 new species of the suborder Cotylea.

Melloplana ferruginea and Pseudoceros bicolor are found in all 8 regions.

Quantitative analysis at 7 regions identified 67 species. The sample based rarefaction curve did not reach asymptote and the species richness estimator (Chao2) stabilized at 94 species. Under- sampling is due to cryptic behavior and dull coloration of many polyclads particularly acotyleans, the high number of rare species (49% =singletons and doubletons), and species of restricted range (uniques andduplicates).

Alpha diversity (mean site species richness SRs) washighly variable ranging from no polyclads (in 4 sites)to 8. There was a weak positive relation to longitude(rs = 0.12, p = 0.04, n = 62), sites in USVI were mostspecies rich.

Beta diversity (Whittaker’s beta diversity), species turnover between site, was greatest forcotylean species and highest in Florida.

Gamma diversity (regional species richness, SRR) was variable and increased from west toeast; 14 species in Belize, 26 species in Jamaica and USVI.

Sample-based rarefaction curves of each habitat showed that reef and seagrass habitats weremost species rich, in particular the reefs of Panama and USVI. In reef habitats cotyleans weresignificantly more species rich than acotyleans (one-factor ANOVA; F1,10 = 6.45, p<0.05).Pseudoceros was the most species-rich genus.

Greater abundances of polyclads were found in intertidal sites. 53% of all polyclads recordedbelonged to Styloplanocera fasciata and Boninia divae which are dominant members of thebenthic epifauna in intertidal coral rubble and rocky shore habitats, respectively.

Species range size was positively correlated with local abundance, thus common specieswere widely distributed spatially, whilst species of low abundance had strongly compressedrange sizes.

There was little distinction in assemblage structure between region (ANOSIM region: R =0.19, p <0.1%). Implying a level of faunal homogeneity across the Caribbean region. Multiplepairwise comparisons showed greatest similarities between Honduras and Belize, Florida andBelize, Curacao and Jamaica. Faunal differences were most distinct between Curacao andPanama, Honduras and USVI assemblages.

Multidimensional scaling (MDS) of meanreplicates per site showed assemblagesfrom different habitats overlapped but that there was some separation (ANOSIM habitat: R = 0.34, p <0.1%), especially between reef and intertidal habitats.

SIMPER analysis - Species representative of each habitat Reef: Pseudoceros bicolor, Phrikoceros mopsus, Diposthus popeae Seagrass: Enchiridium evelinae Rocky shores: Styloplanocera fasciata, Melloplana ferruginea, Boninia divae, Phaenocelis medvedica Limestone: Melloplana ferruginea, Armatoplana leptalea, Boninia divae

30°

20°

10°

-90° -80° -70°

0 400 miles

N

ATLANTIC OCEAN

CARIBBEAN SEA

PAN

HONBEL

CUR

USVI

JAM

FLO

COL

N

MDS of Caribbean sites according tohabitat type

Melloplana ferruginea Pseudoceros bicolor Styloplanocera fasciata Boninia divae