Bohol Sea Research Articles

Abundance and Distribution of the Larvae of Family Carangidae in the Philippine Waters

A spatio-temporal study on the abundance of the Carangidae larvae in Philippine waters was conducted to minimize the lack of information on their spawning grounds. The study analyzed fish larvae data from M/V DA-BFAR cruises between 2006 and 2018, covering various areas in the Philippines. A total of 589 sampling stations were examined and grouped into seven zones: Batanes-Polillo, Catanduanes-Eastern Samar, Inland waters (Bohol Sea, Davao Gulf, Lagonoy Gulf, Leyte Gulf, Ragay Gulf, Sibuyan Sea, Samar Sea, Tayabas Bay, and the Visayan Sea), Mindanao-Sulawesi Sea, Sulu Sea, West Philippine Sea, and Davao Oriental-Surigao. The results indicated a patchy distribution of carangid larvae, with the highest concentration found in northern Palawan (Sulu Sea and West Philippine Sea areas). The total density of composite samples ranged from 1 to 865 larvae/1000m³. The abundance showed fluctuation over the years, with higher densities in 2016 and 2017 compared to other sampling years. The highest mean density was observed in September 2017 in the West Philippine Sea, while the lowest was recorded in May 2015 in Batanes-Polillo waters. The variations in carangid larvae abundance in Philippine waters are likely related to the species' spawning habits, as the timing of reproduction may vary by region based on ecological factors. Other factors influencing the results include sampling incidence and the sampling period of M/V DA-BFAR.

WITHDRAWN: Distribution and habitat partitioning of cetaceans (Mammalia: Cetartiodactyla) in the Bohol Sea, Philippines

Understanding broad-scale species distribution and finer-scale ecological interactions is essential for conservation. We assessed species richness, distribution, habitat use, and interspecific associations of cetacean in the Bohol Sea, Philippines. During 72 days of dedicated survey (2010–2013), we encountered 12 species of cetacean in 291 sightings, 16.8% of which involved mixed species. We used maximum entropy models to assess species’ habitat suitability and found slope and distance from the coast to be influential contributors to cetacean distribution. To explore habitat use, through foraging ecology and niche segregation of sympatric species, we compared behavioral budgets across species and found significant differences (chi-sq = 21.44; p-value = 0.044). We then used generalized linear models to determine the foraging likelihood in relation to oceanographic features, group size and presence of associated species. Results from model selection complimented those derived from maximum entropy. However, some interspecific exclusion behavior might also occur. Overall, our study suggests that the Bohol Sea supports a high cetacean biodiversity while more complex interspecific dynamics might further shape species’ ecological niches. These results highlight the importance of multispecies ecology and can be used to develop management actions.

Spatial and temporal variation in the genetic structure of Dascyllus trimaculatus (Pomacentridae) in the Bohol Sea

The potential of microsatellite markers to detect the spatial and temporal genetic structure of reef fish populations within a linear distance of 300 km in the absence of geographic barriers was tested in the Bohol Sea, central Philippines, using the three-spot damselfish Dascyllus trimaculatus. A total of 672 samples from 7 populations in the Bohol Sea were processed to determine temporal and spatial patterns of genetic variability using ten previously developed and tested microsatellite markers. The extent of differentiation was determined based on a variance-based measure of population structure FST and RST, and genetic distances Ds , DA, and dm2, each of which makes different assumptions on the process of migration, mutation, selection, and genetic drift. Patterns of temporal and spatial variation were consistent among 36 possible pairs of populations. Reef groups are defined as (1) the Mantigue-Dinagat on the northeast edge of the Bohol Sea; (2) the Selinog and Dapitan islands, to the southwest and central Bohol sea populations (3) Apo and (4) Sumilon to the west, and (5) Balicasag group to the northwest. The presence of structure in the absence of geographic barriers suggests the influence of strong surface circulation patterns that differ from the east to the west side of the region. The consistency of a population’s genetic signatures over multiple temporal sampling dates implies strong habitat selection for genotypes. Genetic breaks were detected at a distance 4x greater than the marine protected area’s average size, suggesting a minimum linear distance for networking of MPAs should be expanded to this scale. KEYWORDS: Conservation, Hardy-Weinberg equilibrium, marine protected area, microsatellite markers, population genetics, reef fish

First confirmed sightings of Blue Whales Balaenoptera musculus Linnaeus, 1758 (Mammalia: Cetartiodactyla: Balaenopteridae) in the Philippines since the 19th century

For over two centuries there were no records of Blue Whales Balaenoptera musculus in the Philippines. Whalers recorded Blue Whales in the Philippines in the 19th century, and the next confirmed sighting in the country was of a mother and calf in 2004. Since then 33 subsequent Blue Whale sightings of potentially one individual were recorded between 2004 and 2019, all within the central region of the Philippines around the Bohol Sea. This individual, recognized through photo-identification, was sighted on at least 13 occasions during eight different years: 2010, 2011, 2012, 2015, 2016, 2017, 2018, and 2019. The geographic location and timing of the sightings (January to July) suggest that Blue Whales in the Philippines may extend the outer range edge of the Indo-Australian population that migrate between western Australia, Indonesia, and East Timor. Blue Whale sightings in the Bohol Sea coincide with times of high ocean productivity, although further investigation is needed to determine if they are actually feeding in this region. Acoustic studies and photo-identification matching with other Blue Whale catalogues will clarify the stock identity of Blue Whales in the Philippines and their relation to the rest of the Blue Whale population, with implications for the conservation of this endangered species across multiple jurisdictions.

Stock Assessment of Parrotfishes “Molmol” (Sub-Family Scarinae, Family Labridae) in the Major Fishing Grounds of Bohol, Central Visayas

The issue on the overfishing of parrotfishes, locally known as “molmol” (subfamily Scarinae under family Labridae), in the coastal waters of Bohol province in Central Visayas has been raised by the Provincial Agricultural and Fishery Council (PAFC) of Bohol through Resolution No. 1 series of 2018 that pushes for the implementation of “open and closed fishing season” of all parrotfishes in the entire province. In any management intervention, baseline assessment of the stocks in question should be done as a significant basis for appropriate measures to be taken, thus this study. In Bohol, apart from the economic value, they carry essential functions in maintaining the ecological balance in the reef ecosystem. Parrotfishes are considered economically important as preferred fish among locals and tourists. The stock assessment of parrotfishes in Danajon Bank in the Bohol Sea and Cebu Strait was conducted by the National Stock Assessment Program (NSAP) Region 7 from 2015 to 2018 in 16 coastal municipalities of Bohol. It recorded 24 Scarine species across six genera. The green humphead parrotfish (Bolbometopon muricatum), categorized as vulnerable under the International Union for Conservation of Nature (IUCN) red list, was noted in Cebu Strait in 2015. Scarus ghobban, comprising 82.25%, dominated the catch in Danajon Bank; Scarus forsteni (30.07%) in Bohol Sea; and Chlorurus sordidus (58.45%) in Cebu Strait. Among the Scarines, S. ghobban dominated across fishing grounds from 2015 to 2018 with an aggregate of 10,267.69 kg (or 63.94%) monitored catch equivalent to 0.26% relative to all other species surveyed in the same period. The assessment also indicated that among the 22 fishing gear types being observed as used in catching parrotfishes, speargun is the most prevalent or frequently used. Moreover, the same assessment showed that the catch seasonality of S. ghobban determined from spear gun appears to be abundant during the first quarter in a year; in June, August, and December when higher monthly mean Catch per Unit Effort (CPUE) were also noted. However, the annual mean CPUE of speargun has decreased from 11.93 kg/day in 2017 to 9.22 kg/day in 2018. Population parameters of S. ghobban as the top one species were estimated using the FAO-ICLARM Stock Assessment Tools (FISAT) software and Froese Indicator Tool. Biological indicators for S. ghobban show signs of overfishing as reflected on its high fishing mortality (F/M), decreasing average length below maturity length, decreasing catch per unit effort in the current year, low percentage of mature in the catch, and increasing exploitation ratio (E). All of which already breached the limit reference points. In 2017 and 2018, the mature size composition of the catch was only 1.9 percent and 0.3 percent, respectively, far off from the 90-100% target and below the 50% limit. The values indicate that majority of the samples were small sizes; however, it cannot be determined if they were juveniles since this study excludes reproductive sampling. Optimum length (Lopt) was estimated at 29 cm (Total Length); lengths within ± 10% Lopt range at 26.1 to 31.9 cm and megaspawner at 31.9 cm up. Based on the results, suggested recommendations are indicated herein for possible consideration of the policymakers.

Bir Küçük Adanın Büyük Turizm Başarısı: Camiguin Adası Örneği

Mindanao adasının kuzeyinde ve Bohol denizinin güneyinde yer alan Camiguin adası Filipinlerin en önemli ve en ilginç 25 turizm merkezinden biridir. Çok sayıda volkanik dağ, lagün gölü, kaplıca, mağara ve ilginç şelale barındıran ada dünyanın en iyi 10 dalgıçlık merkezlerinden biri olarak seçilmiştir. Camiguin adasının en büyük turizm avantajlarından birisi küçük yüzölçümüne sahip olmasına rağmen çok çeşitli turizm olanakları, çok sayıda kaliteli konaklama tesisi ve zengin rekreasyon faaliyetlerini aynı anda sunabilmesidir. Bu çalışmada Filipinler Cumhuriyeti’nde ve Mindanao Adalar Grubu’nda yer alan Camiguin adasının başlıca coğrafi özellikleri ve turizm potansiyeli irdelenmiştir. Bu araştırmada adanın coğrafi konumu, doğal ve beşeri özellikleri tartışıldığı gibi turizm çekicilikleri ve başlıca turizm kaynakları da kısaca ele alınmıştır. Adanın başlıca plajları, kentleri, şelaleleri, mağaraları, volkanları, inanç merkezleri ve tarihsel-kültürel çekicilikleri irdelenerek adanın turizm potansiyeli resmedilmeye çalışılmıştır. Çalışmanın sonuç kısmında, Camiguin adasının en büyük turizm avantajları nelerdir sorusuna yanıt aranmıştır

Life History, Growth, and Reproductive Biology of Four Mobulid Species in the Bohol Sea, Philippines

In light of the global decline of mobulid populations and the necessity for sustainable fisheries management, baseline data for population dynamics were collected from a targeted fishery in the Bohol Sea, Philippines. This study focused on life-history parameters and reproductive cycles of four mobulid rays (Mobula thurstoni, M. japanica, M. tarapacana, and Manta birostris), and re-estimated their intrinsic population growth rates. Size and reproductive data were collected from 1,509 specimens (30% of catch) landed in two fishing seasons in 2015 and 2016. Size-at-birth was reviewed, and analysis of the embryos and follicles did not show any clear seasonality in the reproductive cycle, but supported an interbreeding interval. Females of all species matured at a larger size than males, and exhibited a larger size-at-pregnancy than -at-maturity. This delay in reproduction resulted in population growth rates lower than the actual rmax when based on size-at-pregnancy (rmat=rmax=0.016-0.055 year-1 and rpreg=0.008-0.044 year-1), and a population doubling time of 15.8-86.6 years. This study suggests that population growth rates previously reported were overestimated. In light of the Convention on International Trades of Endangered Species (CITES) and Convention on Migratory Species (CMS) assessments, while fisheries management should reflect the delayed maturation of these species and the slower population growth potential, at the current status of these population, the sustainability of any exploitation level seems unrealistic and strongly discouraged.

Satellite tracking of juvenile whale sharks in the Sulu and Bohol Seas, Philippines.

The whale shark Rhincodon typus was uplisted to ‘Endangered’ in the 2016 IUCN Red List due to >50% population decline, largely caused by continued exploitation in the Indo-Pacific. Though the Philippines protected the whale shark in 1998, concerns remain due to continued take in regional waters. In light of this, understanding the movements of whale sharks in the Philippines, one of the most important hotspots for the species, is vital. We tagged 17 juvenile whale sharks with towed SPOT5 tags from three general areas in the Sulu and Bohol Seas: Panaon Island in Southern Leyte, northern Mindanao, and Tubbataha Reefs Natural Park (TRNP). The sharks all remained in Philippine waters for the duration of tracking (6–126 days, mean 64). Individuals travelled 86–2,580 km (mean 887 km) at a mean horizontal speed of 15.5 ± 13.0 SD km day−1. Whale sharks tagged in Panaon Island and Mindanao remained close to shore but still spent significant time off the shelf (>200 m). Sharks tagged at TRNP spent most of their time offshore in the Sulu Sea. Three of twelve whale sharks tagged in the Bohol Sea moved through to the Sulu Sea, whilst two others moved east through the Surigao Strait to the eastern coast of Leyte. One individual tagged at TRNP moved to northern Palawan, and subsequently to the eastern coast of Mindanao in the Pacific Ocean. Based on inferred relationships with temperature histograms, whale sharks performed most deep dives (>200 m) during the night, in contrast to results from whale sharks elsewhere. While all sharks stayed in national waters, our results highlight the high mobility of juvenile whale sharks and demonstrate their connectivity across the Sulu and Bohol Seas, highlighting the importance of the area for this endangered species.

Mobulid rays feed on euphausiids in the Bohol Sea.

Mobulid rays have a conservative life history and are caught in direct fisheries and as by-catch. Their subsequent vulnerability to overexploitation has recently been recognized, but fisheries management can be ineffective if it ignores habitat and prey preferences and other trophic interactions of the target species. Here, we assessed the feeding ecology of four mobulids (Manta birostris, Mobula tarapacana, M. japanica, M. thurstoni) in the Bohol Sea, Philippines, using stomach contents analysis of fisheries specimens landed between November and May in 2013–2015. We show that the mobulids feed heavily on euphausiid krill while they are in the area for approximately six months of the year. We found almost no trophic separation among the mobulid species, with Euphausia diomedeae as the major prey item for all species, recorded in 81 of 89 total stomachs (91%). Mobula japanica and M. thurstoni almost exclusively had this krill in their stomach, while M. tarapacana had a squid and fish, and Ma. birostris had myctophid fishes and copepods in their stomachs in addition to E. diomedeae. This krill was larger than prey for other planktivorous elasmobranchs elsewhere and contributed a mean of 61 364 kcal per stomach (±105 032 kcal s.e., range = 0–631 167 kcal). Our results show that vertically migrating mesopelagic species can be an important food resource for large filter feeders living in tropical seas with oligotrophic surface waters. Given the conservative life history of mobulid rays, the identification of common foraging grounds that overlap with fishing activity could be used to inform future fishing effort.

Characteristics of a previously undescribed fishery and habitat for Manta alfredi in the Philippines

Seven species of mobulid rays occur in the Philippines, six of which, including the Giant Manta Ray (Manta birostris) are caught directly or indirectly. In the Bohol Sea, mobulids have been fished since at least the nineteenth century yet the extent is not well-understood. A second species of manta, Manta alfredi was taxonomically resurrected in 2009 and also only recently been confirmed to occur in the Philippines. This study aimed to identify and describe the presence of and fishery for M. alfredi in a previously unknown area of occurrence in the Philippines. Key informant interviews, observation of catch landings, and tissue sample collection were conducted in a fishing village off Dinagat Island. Based on morphological examination and through DNA barcoding using the mitochondrial DNA CO1 gene of tissue samples it was verified that the species targeted in this area is the reef manta ray, Manta alfredi. Local ecological knowledge of the fishers provided important information on the extent and characteristics of the fishery. This relatively recent ray fishery in the Surigao Strait is the source of mobulids during the off-fishing season in Bohol with fishers from this area transporting and selling their processed catches to Bohol. The description of this fishery and habitat for the reef manta ray in the Surigao Strait is important in the understanding of the status of the species in the Philippines and in designing a management framework.

The History and Characteristics of the Mobulid Ray Fishery in the Bohol Sea, Philippines.

The fishery for mobulid rays, also known as devil rays, has been practiced in the Bohol Sea for over a century yet very little is known about its history and characteristics. This study provides the first detailed description of the mobulid ray fishery in the Bohol Sea, Philippines. It describes the history and evolution of the fishery from the 19th century to 2013. It characterizes the fishery based on the species targeted, gears used, the organization, catch distribution, processing, monetary value, and the market of its by-products. This paper also analyses the changes that occurred through time, the management of the fishery and the drivers of the fishery. A multi-disciplinary approach was employed by combining ethno-historical research methods and catch landing monitoring in four primary sites within the Bohol Sea. This fishery began as an artisanal fishery using sail and row boats equipped with harpoons and gaff hooks practiced in at least four coastal villages in Bohol, Camiguin and Limasawa. The fishing fleet has decreased since the beginning of the 20th century however, with the motorization of the fishery and shift to the use of gillnets, the extent of the fishing grounds and market of the products have expanded. Four species of mobulid rays are caught in the Bohol Sea: Manta birostris, Mobula japanica, Mobula thurstoni and Mobula tarapacana. A fifth species, targeted by a fishing community off Dinagat as an off-shoot of the Bohol fishery is most likely the Manta alfredi. Currently, the fishery for mobulids is centered in Bohol Province where it has been practiced longest. The monetary value of mobulids in this region has increased and the dependence of fishing communities for their livelihood is significant. The unique characteristics of this fishery and the socio-cultural context within which it operates merits a thorough investigation in order to design the appropriate management strategy.

First records of the reef manta ray Manta alfredi in the Bohol Sea, Philippines, and its implication for conservation

We report the occurrence of the reef manta ray Manta alfredi Krefft 1868 in the Bohol Sea, Philippines, based on photographic evidence from boat-based surveys and a fishery specimen. Despite previous anecdotal reports from the diving industry and over a century of extensive targeted fisheries for mobulid rays in the Philippines, it was not until recently that the species was first confirmed in the country at the Tubbataha Reefs Natural Park, Palawan. Our results confirm the presence of M. alfredi in the Visayas region of the Philippines, extending the current range for the species from the Sulu Sea over 600 km eastwards. Its presence in a region with an active mobulid fishery has important implications for the conservation and management of M. alfredi in the country. We highlight the need to understand the distribution of M. alfredi in the region and make management recommendations based on the present study.

Two new species of the stenopodidean shrimp genus Spongiocaris Bruce & Baba, 1973 (Crustacea: Decapoda: Spongicolidae) from the Indo-West Pacific.

Two new species of the deep-water spongicolid genus Spongiocaris Bruce & Baba, 1973, are described and illustrated from two localities in the Indo-West Pacific. Spongiocaris panglao n. sp. is described on the basis of material from the Bohol Sea, the Philippines, at depths of 220-731 m. Spongiocaris tuerkayi n. sp. is described on the basis of material from Atlantis Bank in the southwestern Indian Ocean at depths of 743-1053 m. Among eight known congeners, both new species appear close to S. semiteres Bruce & Baba, 1973, differing in the rostral length and armature, shape of the carapace, telsonal armature, development of the grooming apparatus of the first pereopod and shape of the third pereopod chela. An identification key to the species currently assigned to Spongiocaris is presented.

Predicting reef fish connectivity from biogeographic patterns and larval dispersal modelling to inform the development of marine reserve networks

Developing networks of no-take marine reserves is often hindered by uncertainty in the extent to which local marine populations are connected to one another through larval dispersal and recruitment (connectivity). While patterns of connectivity can be predicted by larval dispersal models and validated by empirical methods, biogeographic approaches have rarely been used to investigate connectivity at spatial scales relevant to reserve networks (10's–100's of km). Here, species assemblage patterns in coral reef fish were used together with an individual-based model of dispersal of reef fish larvae to infer patterns of connectivity in a ∼300km wide region in the Philippines that included the Bohol Sea and adjacent bodies of water. A dominant current flows through the study region, which may facilitate connectivity among >100 no-take reserves. Connectivity was first investigated by analysing data on the presence/absence of 216 species of reef fish and habitat variables across 61 sites. Hierarchical clustering of sites reflecting species assemblage patterns distinguished a major group of sites in the Bohol Sea (Bray–Curtis similarity >70%) from sites situated in adjacent bodies of water (bays, channels between islands and a local sea). The grouping of sites could be partly explained by a combination of degree of embayment, % cover of sand and % cover of rubble (Spearman rank correlation, ρw=0.42). The individual-based model simulated dispersal of reef fish larvae monthly for three consecutive years in the region. The results of simulations, using a range of pelagic larval durations (15–45 days), were consistent with the species assemblage patterns. Sites in the model that showed strongest potential connectivity corresponded to the majority of sites that comprised the Bohol Sea group suggested by hierarchical clustering. Most sites in the model that exhibited weak connectivity were groups of sites which had fish assemblages that were least similar to those in the Bohol Sea group. Concurrent findings from the two approaches suggest a strong influence of local oceanography and geography on broad spatial patterns of connectivity. The predictions can be used as an initial basis to organise existing reserves to form ecologically meaningful networks. This study showed that species assemblage patterns could be a viable supplementary indicator of connectivity if used together with predictions from a larval dispersal model and if the potential effect of habitat on the structuring of species assemblages is taken into consideration.

Ventilation of the Sulu Sea retrieved from historical data

Based on historical observations, ventilation of the Sulu Sea (SS) is investigated and, its interbasin exchange is also partly discussed. The results suggest that near the surface the water renewal process not only occurs through the Mindoro Strait (MS) and the Sibutu Passage, but also depends on the inflows through the Surigao Strait and the Bohol Sea from the Pacific and through the Balabac Strait from the South China Sea (SCS). Both inflows are likely persistent year round and their transports might not be negligible. Below the surface, the core layer of the Subtropical Lower Water (SLW) lies at about 200 m, which enters the SS through the Mindoro Strait not hampered by topography. Moreover, there is no indication of SLW inflow through the Sibutu Passage even though the channel is deep enough to allow its passage. The most significant ventilation process of the SS takes place in depths from 200 m to about 1 200 m where intermediate convection driven by quasi-steady inflows through the Mindoro and Panay straits (MS-PS) dominates. Since the invaded water is drawn from the upper part of the North Pacific Intermediate Water (NPIW) of the SCS, it is normally not dense enough to sink to the bottom. Hence, the convective process generally can only reach some intermediate depths resulting in a layer of weak salinity minimum (about 34.45). Below that layer, there is the Sulu Sea Deep Water (SSDW) homogeneously distributed from 1 200 m down to the sea floor, of which the salinity is only a bit higher (about 34.46) above the minimum. Observational evidence shows that hydrographic conditions near the entrance of the MS in the SCS vary significantly from season to season, which make it possible to provide the MS-PS overflow with denser water of higher salinity sporadically. It is hence proposed that the SSDW is derived from intermittent deep convection resulted from property changes of the MS-PS inflow.

Basin isolation and oceanographic features influencing lineage divergence in the humbug damselfish <I>(Dascyllus aruanus)</I> in the Coral Triangle

The Coral Triangle is a hotspot for marine species diversity as well as for intraspecific genetic diversity. Here, we used nuclear RAG2 and mitochondrial D-Loop genes to identify deep genetic divergence among Dascyllus aruanus (Linnaeus, 1758) populations across relatively short scales within the Coral Triangle. Mitochondrial clades different by >20 mutational steps were completely isolated from one another across the distance between Java and the Lesser Sunda Islands, and also showed frequency differences in the eastern and western Philippines. Evidence for population structure in the Sulu Sea and at the Lesser Sunda Islands was also identified. Our results suggest that the Sulu Sea Throughflow, Bohol Sea Throughflow, Indonesian Throughflow, signatures of extinction events from Pleistocene land barriers, and other past and present forces may be potential factors leading to lineage divergence of D. aruanus, and that these hypotheses should be tested in further studies.

A new species of the pagurid hermit crab genus Lophopagurus McLaughlin, 1981 (Crustacea: Decapoda: Anomura) from French Polynesia, and additional record of L. indonesiensis McLaughlin, 1997 from the Philippines.

Two species of the pagurid hermit crab genus Lophopagurus McLaughlin, 1981 are reported herein. Lophopagurus (Lophopagurus) minimus n. sp., described on the basis of two females from Tuamotu Archipelago, French Polynesia, appears closest to L. (L.) nanus (Henderson, 1888), but is easily distinguished from the latter by the different shape of the ocular peduncles and the less developed armature of the right cheliped. A single female from the Bohol Sea, the Philippines, is identified with L. (Australeremus) indonesiensis McLaughlin, 1997, a species for which possible synonymy with L. (A.) triserratus has been suggested. The newly collected specimen confirms the validity of the species and represents its second record since the original description.

Additional records of the pagurid hermit crab genus Trichopagurus de Saint Laurent, 1968 (Crustacea: Decapoda: Anomura), with description of a new species from the Philippines

The pagurid hermit crab genus Trichopagurus de Saint Laurent, 1968 is currently represented by three shallow water spe- cies from the tropical Indo-West Pacific region. In this paper, three species of the genus, including one new species, are reported. Trichopagurus tenuidactylus n. sp. is described on the basis of a single ovigerous female from the Bohol Sea, the Philippines, and compared with two close relatives, T. asper Komai & Poupin, 2012 and T. macrochela Komai & Os- awa, 2005. New locality records are provided for T. macrochela (the Philippines) and T. trichophthalinus (Forest, 1954) (Taiwan and Marianas). An identification key to the four species of the genus is presented.

A new species of ocellated Xanthias Rathbun, 1897 (Crustacea: Decapoda: Brachyura: Xanthidae) from the Bohol Sea, Philippines.

A new species of xanthid crab (Brachyura: Xanthidae) is described from the Bohol Sea in the central Philippines. Xanthias joanneae sp. nov. is most similar in morphology to X. maculatus Sakai, 1961 (type locality: Sagami Bay, Japan), particularly in the presence of distinctive ocelli on the carapace and pereopods. It can be separated from this species by the greater number of ocelli on the dorsal surface of the carapace, wider teeth separated by narrow notches on the carapace anterolateral margin, absence of longitudinal ridges on the external surface of the chelar palm, shorter and stouter ambulatory legs, narrower male anterior thoracic sternum, and stouter G 1.

A New Genus and New Species of Paguridae (Crustacea: Decapoda: Anomura) from the Bohol Sea, the Philippines

A new genus and new species of the hermit crab family Paguridae is described and illustrated on the basis of three specimens collected from off Balicasag Island, Bohol Sea, the Philippines. The new genus, Pliopagurus, is referred to the “Pylopagurus-Tomopagurus” group on account of its having 11 pairs of biserial gills and paired first pleopods in females, and appears closest to Lophopagurus McLaughlin, 1981. The possession of short sexual tubes on both coxae of the fifth pereopods in the male and the lack of a median crest or dorsolateral keel of the left chela distinguish Pliopagurus from Lophopagurus. An emended key to the genera of the “Pylopagurus-Tomopagurus” group is presented.