Two new species of Travisiidae (Annelida, Sedentaria) from Thailand.

Two new species of Travisiidae, Travisia satunensis sp. nov. and T. thailandensis sp. nov., were collected from different locations in Thailand waters. Travisia satunensis sp. nov. was collected in the Andaman Sea, at 214 m water depths. Travisia thailandensis sp. nov. was collected from offshore petroleum concession areas in the Gulf of Thailand, at 5080 m water depths. Travisia satunensis sp. nov. differs from all other species by having branched annulated branchiae on chaetigers 235, each annulated with a single filament, chaetae throughout the body and pygidium with 10 anal cirri, six digitiform and four short cirri, alternately arranged. Travisia thailandensis sp. nov. differs from all other species by having 21 pairs of cirriform, annulated branchiae from chaetiger 2, a mid-ventral groove along body, two last segments achaetous, and nephridiopores on chaetigers 714. A key for Travisia species from the Indo-Pacific region is also provided.

Two new species of Ancistrosyllis McIntosh, 1878 (Annelida: Pilargidae) from the Gulf of Thailand, Western Pacific.

Two new species of Pilargidae, Ancistrosyllis eidimtaiteae sp. nov. and A. suksani sp. nov., are described from the Gulf of Thailand. These Ancistrosyllis are characterized by having a median and two lateral antennae. Ancistrosyllis eidimtaiteae sp. nov. differs from all other species in the group by having brown pigmentation and by having both short antennae and tentacular cirri, first notopodial hooks from chaetiger 3, and a single type of neurochaetae (long non-limbate capillaries with bifid tips). Ancistrosyllis suksani sp. nov. can be distinguished from other species of Ancistrosyllis by the presence of the first notopodial hooks from chaetiger 4 and three types of neurochaetae (short, stout, falcates with a subdistal small guard, short limbates, and long bifid non-limbates). An updated key to the Ancistrosyllis species of this group is also provided.

Four new species of Pilargidae (Annelida: Pilarginae) from the Gulf of Thailand.

Four new species belonging to the Family Pilargidae, Ancistrosyllis kornkanokae sp. nov., A. nakkaritae sp. nov., Cabira saithipae sp. nov., and C. thailandica sp. nov. were collected from 927 m depth in soft sediments in the Songkhla Sea, Gulf of Thailand. Ancistrosyllis kornkanokae sp. nov. can be distinguished from other species in the genus by the presence of a small median antenna on the prostomium; two pairs of elongate tentacular cirri; and short limbate neurochaetae with unidentate curved pointed tips. Ancistrosyllis nakkaritae sp. nov. is characterized by having a conspicuous median antenna and elongate lateral antennae longer than palps; and short limbate neurochaetae with bifid tips. While Cabira saithipae sp. nov. is characterized by the presence of the first notopodial hook at chaetiger eight, large, conical papillae ont chaetigers 717 and the presence of both short, recurved tipped and short, curved tip chaetae in anterior chaetigers. Cabira thailandica sp. nov. is distinguished from other species in the genus by the first notopodial hooks occurring at chaetiger seven and the presence of long, non-limbate capillary neurochaetae with bidentate tips. Updated keys to the genera Ancistrosyllis and Cabira are also provided.

Three new species of Sternaspidae (Annelida: Sedentaria) from Thailand.

In this contribution, three new species of sternaspids collected from sediments along the coast of southern Thailand are described: Petersenaspis apinyae sp. nov. from a depth of 5080 m offshore in the Gulf of Thailand; P. narisarae sp. nov. from 9 m depth in the Songkhla Sea, Gulf of Thailand; and P. pakbaraensis sp. nov. from tidal mudflats on the Andaman Coast. All three species resemble P. palpallatoci Sendall Salazar-Vallejo, 2013. They differ mainly in the pigmentation and shape of the shield, the number of ventral chaetae and chaetae at the posterior shield, body papillae, and size of the abdomen. Further, P. apinyae sp. nov. is clearly distinguished from other species of the genus by having dark orange to red butterfly wing-shaped shields, with strongly curved anterior margins. P. narisarae sp. nov. differs from other species by having concentric colored bands over shields and an expanded oval abdomen. P. pakbaraensis sp. nov. can be distinguished from other species by its dark brown-purple shield and laterally expanded fan. These three species have a unique character in their branchial plates: long brownish filaments. A key to the identification of all species of Petersenaspis is included.

Two new species of Sphaerodoridae (Annelida) from the Gulf of Thailand.

Despite being a great species-rich area, the Gulf of Thailand has been relatively poorly studied and new species are awaiting to be described. In the present study two new species of Sphaerodoridae (Annelida), Geminofilum thailandica sp. nov. and Sphaerodoridium songkhlaensis sp. nov. were collected in shallow soft bottoms at Songkhla Sea. Geminofilum thailandica sp. nov. is characterised by bearing sessile and elongated dorsal macrotubercles, arranged in two transverse rows per segment, lacking other dorsal papillae, having parapodia with a single papilla at the base and compound chaetae with blades 4-6 times as long as wide and serration showing variation within fascicles. Sphaerodoridium songkhlaensis sp. nov. can be distinguished from other congeners by the singular morphology of the short stalked dorsal macrotubercles as inverted cones, with a conspicuous rim encircling the flattened distal surface, and two longitudinal rows of smaller sessile tubercles, as inverted cones, along ventrum, with four pairs of tubercles per segment. Chaetae show variation in the serration within fascicles. The present study highlights the need for further biodiversity studies on benthic communities in this area.

Description of two new species of Paraonidae (Annelida) from the Gulf of Thailand, Western Pacific.

Two new species of Aricidea Webster, 1879 (Paraonidae), Aricidea (Acmira) anusakdiisp. nov. and Aricidea (Aricidea) thammapinanaesp. nov. were collected from 10-26.5 m depth, in soft bottoms with mud mixed with sand and shells at Songkhla Sea, the Gulf of Thailand between 2011-2018. Aricidea (Acmira) anusakdiisp. nov. is clearly distinguished from other species of the subgenus Acmira by having a rounded bilobed prostomium divided by a slight notch on the anterior margin; red pigments on the subdistal to the tip of each branchia (new character); two prebranchial chaetigers; 48-68 pairs of branchiae; and modified neurochaetae as strong curved spines with blunt shafts surrounded by pubescence from chaetigers 19-44. On the other hand, Aricidea (Aricidea) thammapinanaesp. nov. can be separated from other members of the subgenus Aricidea by the presence of a biarticulated median antenna; distinctive notopodial lobes as broad triangular with short distal protuberances on chaetiger 3, 4-8 pairs of branchiae; and modified neurochaetae as bidentate neurochaetae with a long pubescent subterminal arista on the concave side. All data have been archived and are freely available from the Dryad Digital Repository (https://doi.org/10.5061/dryad.hqbzkh1cn).

The complete mitochondrial genomes of needle corals, Seriatopora spp. (Scleractinia: Pocilloporidae): an idiosyncratic atp8, duplicated trnW gene, and hypervariable regions used to determine species phylogenies and recently diverged populations.

Complete DNA sequences were determined for the mitochondrial (mt) genomes of the needle corals, Seriatopora caliendrum (17,011bp) and S. hystrix (17,060bp). Gene arrangement of the Seriatopora mt genomes is similar to the 14 currently published scleractinian mitogenomes with three unusual features, including an idiosyncratic atp8, a duplicated trnW (tRNA(TRP)), and a putative control region located between atp6 and nad4. Atp8, located between duplicate trnW genes, showed relatively low amino acid similarity (25.6-34.6%) with those of published scleractinian corals. A reverse-transcription polymerase chain reaction confirmed the transcription of this novel atp8 gene in Seriatopora. A duplicated trnW was detected in the region close to the cox1 gene and shares the highly conserved primary and secondary structure of its original counterpart. The intergenic spacer between atp6 and nad4, which contains several distinct repeated elements, is being designated as the putative control region in the Seriatopora mt genomes. Evaluation of the molecular evolution of several protein-coding genes and intergenic spacers showed 3- to 4-fold higher divergence rates among populations or between species than those published for scleractinian mt genomes. This study not only successfully revealed the phylogenies of S. hystrix and S. caliendrum from the West Pacific Ocean by mtDNA, but also highlighted the potential utilities of mt hypervariable regions in phylogenetic construction below the species level for Seriatopora.

Effects of Self-Guided Snorkeling Trails on Corals in a Tropical Marine Park.

Underwater trails are intended as interpretative tools in marine parks, but concentrating divers and snorkelers in defined areas may negatively affect the surrounding environment. We examined spatial and temporal patterns in the effects of use of underwater trails on coral reef flats in the Great Barrier Reef Marine Park, Australia. Changes in benthic assemblages were assessed on two new trails used by snorkelers, two unused (control) trails, and two undisturbed areas. Total percent coral cover, numbers of broken colonies, and living coral fragments were counted 6 months before and 6 months after the new trails began to be used. Spatial patterns of effects around concentrated nodes of use were determined by stratified sampling around and away from the interpretative signs within each trail. Despite comparatively low levels of use (approximately 15 snorkelers per trail per week), snorkelers caused significant damage to corals along the trails. Branching corals (non-Acropora branching corals and Millepora spp.) were most affected. More damage occurred near the interpretative signs than elsewhere on the trails. The numbers of broken branches and damaged coral colonies in the snorkeling trails increased rapidly but stabilized within 2 months of the commencement of use. There was no significant change in overall benthic assemblages within the trails after 6 months of use by snorkelers. Although concentrating snorkelers within confined trails caused increased damage to corals, the effects can be mitigated by appropriate design and placement of the trails and by managing the behavior of snorkelers. Interpretative information should warn users about the damage they may cause when swimming along the trails. Managing the behavior of snorkelers in the water is likely to be more effective in reducing damage than simply applying fixed limits to the amount of use the trails receive.

RESUMEN: Los senderos submarinos tienen la intención de servir como herramientas interpretativas en los parques marinos, pero la concentración de buzos y buceadores libres en áreas definidas puede tener un efecto negativo en el ambiente de los alrededores. Examinamos los patrones temporales y espaciales de los efectos del uso de senderos submarinos en relieves de arrecifes de coral en el arrecife del Parque Marino de la Gran Barrera de Arrecifes en Australia. Los cambios en los ensamblajes bénticos fueron evaluados en dos senderos nuevos usados por buceadores libres, dos senderos sin usar (controles) y dos áreas sin perturbar. Evaluamos el porcentaje de cobertura de coral, el número de colonias rotas, y fragmentos de coral vivo 6 meses antes y seis meses después de que se iniciara el uso de los senderos nuevos. Los patrones espaciales de los efectos alrededor de nódulos concentrados de uso fueron determinados por un muestreo estratificado alrededor y en sitios lejanos de las señales interpretativas de cada sendero. A pesar de los niveles significativamente bajos de uso (∼15 buceadores libres/sendero/semana), los buceadores libres causaron un daño significativo a los corales a lo largo de los senderos. Los corales ramificados (spp. de corales que no pertenecen a Acropora o Millepora) fueron los más afectados. Se observó más daño cerca de las señales interpretativas que en cualquier otra parte del sendero. Los números de ramas rotas y de colonias de coral dañadas en los senderos se incrementaron rápidamente, pero se estabilizaron a los dos meses de haber iniciado el uso de los senderos. No hubo un cambio significativo dentro de los senderos después de seis meses de uso. A pesar de que la concentración de buceadores libres dentro de senderos confinados incrementó el daño a los corales, los efectos pueden ser mitigados mediante el diseño y la ubicación apropiada de los senderos y mediante el manejo de la conducta de los buceadores libres. La información interpretativa debería prevenir a los usuarios sobre el daño que ellos mismos pueden ocasionar cuando nadan en estos senderos. El manejo de la conducta de los buceadores libres en el agua probablemente sea más efectivo en la reducción del daño que la simple aplicación de límites fijos a la cantidad de uso que un sendero puede recibir.