Global collision-risk hotspots of marine traffic and the world's largest fish, the whale shark.

Marine traffic is increasing globally yet collisions with endangered megafauna such as whales, sea turtles, and planktivorous sharks go largely undetected or unreported. Collisions leading to mortality can have population-level consequences for endangered species. Hence, identifying simultaneous space use of megafauna and shipping throughout ranges may reveal as-yet-unknown spatial targets requiring conservation. However, global studies tracking megafauna and shipping occurrences are lacking. Here we combine satellite-tracked movements of the whale shark, Rhincodon typus, and vessel activity to show that 92% of sharks' horizontal space use and nearly 50% of vertical space use overlap with persistent large vessel (>300 gross tons) traffic. Collision-risk estimates correlated with reported whale shark mortality from ship strikes, indicating higher mortality in areas with greatest overlap. Hotspots of potential collision risk were evident in all major oceans, predominantly from overlap with cargo and tanker vessels, and were concentrated in gulf regions, where dense traffic co-occurred with seasonal shark movements. Nearly a third of whale shark hotspots overlapped with the highest collision-risk areas, with the last known locations of tracked sharks coinciding with busier shipping routes more often than expected. Depth-recording tags provided evidence for sinking, likely dead, whale sharks, suggesting substantial "cryptic" lethal ship strikes are possible, which could explain why whale shark population declines continue despite international protection and low fishing-induced mortality. Mitigation measures to reduce ship-strike risk should be considered to conserve this species and other ocean giants that are likely experiencing similar impacts from growing global vessel traffic.

Buccal venom gland associates with increased of diversification rate in the fang blenny fish Meiacanthus (Blenniidae; Teleostei).

At the macroevolutionary level, many mechanisms have been proposed to explain explosive species diversification. Among them morphological and/or physiological novelty is considered to have a great impact on the tempo and the mode of diversification. Meiacanthus is a genus of Blenniidae possessing a unique buccal venom gland at the base of an elongated canine tooth. This unusual trait has been hypothesized to aid escape from predation and thus potentially play an important role in their pattern of diversification. Here, we produce the first time-calibrated phylogeny of Blenniidae and we test the impact of two morphological novelties on their diversification, i.e. the presence of swim bladder and buccal venom gland, using various comparative methods. We found an increase in the tempo of lineage diversification at the root of the Meiacanthus clade, associated with the evolution of the buccal venom gland, but not the swim bladder. Neither morphological novelty was associated with the pattern of size disparification in blennies. Our results support the hypothesis that the buccal venom gland has contributed to the explosive diversification of Meiacanthus, but further analyses are needed to fully understand the factors sustaining this burst of speciation.

Skipping across the tropics: the evolutionary history of sawtail surgeonfishes (Acanthuridae: Prionurus).

Fishes described as "anti-equatorial" have disjunct distributions, inhabiting temperate habitat patches on both sides of the tropics. Several alternative hypotheses suggest how and when species with disjunct distributions crossed uninhabitable areas, including: ancient vicariant events, competitive exclusion from the tropics, and more recent dispersal during Pliocene and Pleistocene glacial periods. Surgeonfishes in the genus Prionurus can provide novel insight into this pattern as its member species have disjunct distributions inhabiting either temperate latitudes, cold-water upwellings in the tropics, or low diversity tropical reef ecosystems. Here the evolutionary history and historical biogeography of Prionurus is examined using a dataset containing both mitochondrial and nuclear data for all seven extant species. Our results indicate that Prionurus is monophyletic and Miocene in origin. Several relationships remain problematic, including the placement of the Australian P. microlepidotus, and the relationship between P. laticlavius and P. punctatus. Equatorial divergence events between temperate western Pacific habitats occurred at least twice in Prionurus: once in the Miocene and again in the late Pliocene/early Pleistocene. Three species with tropical affinities, P. laticlavius, P. punctatus, and P. biafraensis, form a clade that originated in the Pliocene. These results suggest that a variety of mechanisms may regulate the disjunct distribution of temperate fishes, and provide support for both older and younger equatorial crossing events. They also suggest that interspecific competitive exclusion may be influential in fishes with "anti-equatorial" distributions.

New species of Trimma (Actinopterygii, Gobiidae) from Indonesia, with comments on head papillae nomenclature.

Three new species of the gobiid Trimma are described from Indonesian waters, and a partially reformulated nomenclature for the cephalic sensory papillae of members of this genus is provided. Trimma aturirii possesses two dark oblique stripes on either side of the pupil (blue, edged with red in life, dark brown in preservative), the lower of which continues posteriorly across the dorsal margin of the opercle, with the dorsal half of the body red and the ventral half abruptly white in life. The species has a narrow bony interorbital (≤50% pupil width), a moderate interorbital trench with a slight groove posterodorsal to the eye, no scales on the cheek, opercle or in the predorsal midline, no elongate spines in the first dorsal fin, 9-10 dorsal and 9 anal fin rays, 17-18 (7-11 branched) pectoral fin rays and an unbranched fifth pelvic fin ray. Trimma kardium has a pair of tapering oval red spots which join anteriorly over the anterior region of the hyoid arches, forming an approximate heart-shaped marking on the ventral surface of the head. It has a narrow bony interorbital (≤40% pupil width), a moderate interorbital trench with a slight groove posterodorsal to the eye, 17-18 unbranched pectoral fin rays, 1-5 cycloid scales in the predorsal midline confined to about the middle third of the nape, and a single row of 1-3 cycloid scales along the upper border of the opercle. Trimma trioculatum has a large (slightly greater than pupil diameter in width) round, black, ocellated spot in the first dorsal fin between spines 1 and 5, a second, much smaller black or dark red spot just posterior to the spine of the second dorsal fin and above the basal stripe, a yellow body with a dark purplish or gray head with two distinct red bars across the cheek, no round spots of any colour on the nape, opercle or cheek, a small dark (preserved) or white (alive) spot on the upper pectoral fin base, a narrow bony interorbital (<70% pupil diameter), no elongate spines in the first dorsal fin, 15-16 pectoral fin rays with the middle 4-8 rays branched, a fifth pelvic fin ray with a single dichotomous branch, and 16-17 total gill rakers on the first gill arch.

Trimma helenae (Pisces; Gobioidei), a new species of gobiid fish from Indonesia.

A new species of Trimma, T. helenae, is described from the southeastern lagoon at Penemu Island off the southwest coast of Waigeo, Raja Ampat, Indonesia. The new species has a unique colour pattern when alive, consisting of a yellow anterior half and red posterior half, with four small white spots along the midline of the dorsal and ventral surfaces of the caudal peduncle. It is also the only species of the genus to have a nasal sac that is flush with the snout surface (not raised above the level of the snout or only represented by a nasal pit), and which lacks a raised rim to the posterior nasal pore. Trimma helenae belongs to a group of 12 valid nominal species defined by having a broad bony interorbital region (width 80-100% of pupil diameter), but differs from all of but three of these in having only cycloid scales in the midline and on the sides of the nape. The other members of the group have mostly ctenoid scales in this region.

Spatial connectivity of reef manta rays across the Raja Ampat archipelago, Indonesia.

The reef manta ray Mobula alfredi is present throughout most island groups that form the Raja Ampat archipelago, Indonesia. The species is protected regionally and nationally and is currently managed as a single homogeneous population within the 6.7 million ha archipelago. However, scientific evidence is currently lacking regarding the spatial connectivity and population structure of M. alfredi within this archipelago. Using network analysis and an array of 34 acoustic receivers deployed throughout Raja Ampat between February 2016 and September 2021, we examined the movements of 72 subadult and adult M. alfredi tagged in seven regions of Raja Ampat. A total of 1094 M. alfredi movements were recorded and were primarily concentrated between nearby receiver stations, highlighting frequent local movements within, and limited long-distance movements between regional acoustic receiver arrays. Network analysis revealed highly connected nodes acting as hubs important for M. alfredi movements. A community detection algorithm further indicated clusters within the network. Our results suggest the existence of a metapopulation comprising three demographically and geographically distinct subpopulations within the archipelago. They also reveal the importance of Eagle Rock as a critical node in the M. alfredi movement network, justifying the urgent inclusion of this site within the Raja Ampat marine protected area network.

Identifying priority sites for whale shark ship collision management globally.

The expansion of the world's merchant fleet poses a great threat to the ocean's biodiversity. Collisions between ships and marine megafauna can have population-level consequences for vulnerable species. The Endangered whale shark (Rhincodon typus) shares a circumglobal distribution with this expanding fleet and tracking of movement pathways has shown that large vessel collisions pose a major threat to the species. However, it is not yet known whether they are also at risk within aggregation sites, where up to 400 individuals can gather to feed on seasonal bursts of planktonic productivity. These "constellation" sites are of significant ecological, socio-economic and cultural value. Here, through expert elicitation, we gathered information from most known constellation sites for this species across the world (>50 constellations and >13,000 individual whale sharks). We defined the spatial boundaries of these sites and their overlap with shipping traffic. Sites were then ranked based on relative levels of potential collision danger posed to whale sharks in the area. Our results showed that researchers and resource managers may underestimate the threat posed by large ship collisions due to a lack of direct evidence, such as injuries or witness accounts, which are available for other, sub-lethal threat categories. We found that constellations in the Arabian Sea and adjacent waters, the Gulf of Mexico, the Gulf of California, and Southeast and East Asia, had the greatest level of collision threat. We also identified 39 sites where peaks in shipping activity coincided with peak seasonal occurrences of whale sharks, sometimes across several months. Simulated collision mitigation options estimated potentially minimal impact to industry, as most whale shark core habitat areas were small. Given the threat posed by vessel collisions, a coordinated, multi-national approach to mitigation is needed within priority whale shark habitats to ensure collision protection for the species.

Eviota santanai, a new Dwarfgoby from Timor-Leste (Teleostei: Gobiidae).

Eviota santanai is described based on four specimens from Timor-Leste, taken in 5-8 m depth. In general coloration pattern, the species is most similar to E. latifasciata, but differs in the cephalic sensory-pore system pattern, the absence of an occipital spot, and live color including pinkish-mauve bars. Eviota santanai has a dorsal/anal fin-ray formula of 8/8, 5th pelvic-fin ray absent, some lower pectoral-fin rays branched, and IT and PITO pores absent.

Validation of Pomacentrus novaeguineae, P. umbratilus and P. xanthocercus Allen, Erdmann & Pertiwi (Perciformes: Pomacentridae) from Melanesia and the eastern and central Indian Ocean.

N/A.

A review of the Eviotazebrina complex, with descriptions of four new species (Teleostei, Gobiidae).

The Eviotazebrina complex includes eight species of closely-related dwarfgobies, four of which are herein described as new. The complex is named for Eviotazebrina Lachner & Karnella, 1978, an Indian Ocean species with the holotype from the Seychelles Islands and also known from the Maldives, which was once thought to range into the Gulf of Aqaba and the Red Sea eastward to the Great Barrier Reef of Australia. Our analysis supports the recognition of four genetically distinct, geographically non-overlapping, species within what was previously called E.zebrina, with E.zebrina being restricted to the Indian Ocean, E.marerubrum sp. nov. described from the Red Sea, E.longirostris sp. nov. described from western New Guinea, and E.pseudozebrina sp. nov. described from Fiji. The caudal fin of all four of these species is crossed by oblique black bars in preservative, but these black bars are absent from the four other species included in the complex. Two of the other species within the complex, E.tetha and E.gunawanae are morphologically similar to each other in having the AITO cephalic-sensory pore positioned far forward and opening anteriorly. Eviotatetha is known from lagoonal environments in Cenderawasih Bay and Raja Ampat, West Papua, and E.gunawanae is known only from deeper reefs (35-60 m) from Fakfak Regency, West Papua. The final two species are E.cometa which is known from Fiji and Tonga and possesses red bars crossing the caudal fin (but lost in preservative) and a 9/8 dorsal/anal-fin formula, and E.oculineata sp. nov., which is described as new from New Guinea and the Solomon Islands, and possesses an 8/7 dorsal/anal-fin formula and lacks red caudal bars. Eviotaoculineata has been confused with E.cometa in the past.

Diving behavior of the reef manta ray (Mobula alfredi) in New Caledonia: More frequent and deeper night-time diving to 672 meters.

The interest in reef manta rays (Mobula alfredi) from the scientific community is growing in reaction to the major decline of populations around the world. Studies have highlighted the need to further investigate the spatial ecology of this species to inform conservation and management initiatives. Here we briefly report the results from nine SPLASH10-F-321A pop-off satellite archival tags (PSAT-tags) deployed in New Caledonia that recorded the world's deepest known dives for reef manta rays. All tagged individuals performed dives exceeding 300 m in depth, with a maximum depth recorded of 672 ± 4 m. Diel comparisons revealed that most of the deepest dives occurred during night-time. We hypothesize this deep-diving behaviour is employed to access important food resources at these depths during the night and may also indicate that zooplankton abundance in the surface waters surrounding New Caledonian coral reefs is insufficient to sustain these megafauna. These results add new information on the habitat use of this species in a region where manta behaviour has not previously been studied, and increase the known depth range of M. alfredi by more than 200 m.

Recognizing peripheral ecosystems in marine protected areas: A case study of golden jellyfish lakes in Raja Ampat, Indonesia.

Peripheral marine ecosystems can harbor endemic diversity and attract tourism attention, yet are generally not included in conservation management plans due to their remoteness or inland positioning. A case study in Raja Ampat of seven landlocked marine lakes containing golden jellyfish (Mastigias spp.) was conducted to address the lack of fundamental insights into evolutionary, ecological and social contexts of these ecosystems. An interdisciplinary approach was taken towards identifying the jellyfish lakes as distinct management units in order to incorporate them into existing Marine Protected Areas. Mastigias papua populations showed strong genetic (ϕST: 0.30-0.86) and morphological (F = 28.62, p-value = 0.001) structure among lakes, with putative new subspecies. Risks arising from rapid increase in tourism to Raja Ampat (30-fold since 2007) warrant restrictions on jellyfish lake use. Recommendations are provided for adaptive management and science-based conservation policies for jellyfish lakes across Indonesia.

A new species of Trimma (Pisces; Gobiidae) from the Western Pacific Ocean.

A new species of Trimma, T. wangunui, is described from three localities in the western Pacific (Papua New Guinea, Timor-Leste and the Philippines). It belongs to a small group of species with scales in the predorsal midline, no scales on the cheek or the opercle, all pectoral fin rays unbranched, and a branched fifth pelvic fin ray. It differs from other species in this group in having an elongate second spine of the first dorsal fin which reaches to the bases of the 2nd-8th second dorsal-fin rays when adpressed, in having yellow bars on the head, and in the presence of vertically elongate yellow spots on a brown body when freshly collected.

Comparative phylogeography of two seastars and their ectosymbionts within the Coral Triangle.

Repeated exposure and flooding of the Sunda and Sahul shelves during Pleistocene sea-level fluctuations is thought to have contributed to the isolation and diversification of sea-basin populations within the Coral Triangle. This hypothesis has been tested in numerous phylogeographical studies, recovering an assortment of genetic patterns that the authors have generally attributed to differences in larval dispersal capability or adult habitat specificity. This study compares phylogeographical patterns from mitochondrial COI sequences among two co-distributed seastars that differ in their adult habitat and dispersal ability, and two seastar ectosymbionts that differ in their degree of host specificity. Of these, only the seastar Linckia laevigata displayed a classical pattern of Indian-Pacific divergence, but with only moderate genetic structure (PhiCT = 0.067). In contrast, the seastarProtoreaster nodosus exhibited strong structure (PhiCT = 0.23) between Teluk Cenderawasih and the remainder of Indonesia, a pattern of regional structure that was echoed in L. laevigata (PhiCT = 0.03) as well as its obligate gastropod parasite Thyca crystallina (PhiCT = 0.04). The generalist commensal shrimp, Periclimenes soror showed little genetic structuring across the Coral Triangle. Despite species-specific phylogeographical patterns, all four species showed departures from neutrality that are consistent with massive range expansions onto the continental shelves as the sea levels rose, and that date within the Pleistocene epoch.Our results suggest that habitat differences may affect the manner in which species responded to Pleistocene sea-level fluctuations, shaping contemporary patterns of genetic structure and diversity.

Phylogeography and limited genetic connectivity in the endangered boring giant clam across the Coral Triangle.

The Coral Triangle is the global center of marine biodiversity; however, its coral reefs are critically threatened. Because of the bipartite life history of many marine species with sedentary adults and dispersive pelagic larvae, designing effective marine protected areas requires an understanding of patterns of larval dispersal and connectivity among geographically discrete populations. We used mtDNA sequence data to examine patterns of genetic connectivity in the boring giant clam (Tridacna crocea) in an effort to guide conservation efforts within the Coral Triangle. We collected an approximately 485 base pair fragment of mtDNA cytochrome c oxidase 1 (CO1) from 414 individuals at 26 sites across Indonesia. Genetic structure was strong between regions (phi(ST)=0.549, p < 0.00001) with 3 strongly supported clades: one restricted to western Sumatra, another distributed across central Indonesia, and a third limited to eastern Indonesia and Papua. Even within the single largest clade, small but significant genetic structure was documented (phi(ST)=0.069, p < 0.00001), which indicates limited gene flow within and among phylogeographic regions. Significant patterns of isolation by distance indicated an average dispersal distance of only 25-50 km, which is far below dispersal predictions of 406-708 km derived from estimates of passive dispersal over 10 days via surface currents. The strong regional genetic structure we found indicates potent limits to genetic and demographic connectivity for this species throughout the Coral Triangle and provides a regional context for conservation planning. The recovery of 3 distinct evolutionarily significant units within a well-studied taxonomic group suggests that biodiversity in this region may be significantly underestimated and that Tridacna taxa may be more endangered than currently recognized.

Two new species of blue-eyed Trimma (Pisces; Gobiidae) from New Guinea.

Two new species of Trimma are described from New Guinea, one at the southeastern end at Normanby Island (Milne Bay Province), the other from Cendrawasih Bay, West Papua, on the north-east coast. The dorsal surface of the eye of both species is blue in life, a characteristic not reported elsewhere in the genus. Although the two species look very similar in life, and both occupy similar mesophotic rubble habitats in the 50-70 m depth range, they are separated both genetically (7.7% pairwise genetic distance in COI) and morphologically. Trimma blematium has 16 pectoral fin rays, a branched 5th pelvic fin ray, and 7 papillae in row p, whereas T. meityae has 17-18 pectoral fin rays, an unbranched 5th pelvic fin ray, and 8 papillae in row p. In live specimens, the blue colour over the top of the eyes is much darker in T. blematium than in T. meityae. The type localities are separated by almost 2,000 km (straight-line distance).

Pseudochromis stellatus, a new species of dottyback from Indonesia (Teleostei: Pseudochromidae).

The Pseudochromis reticulatus complex is diagnosed to include species of Pseudochromis with the combination of a pointed caudal fin (rounded with middle rays produced), a reticulated colour pattern on the upper part of the body, dorsal-fin rays modally III,26, anal-fin rays modally III,15, and pectoral-fin rays modally 18. Members of the complex include P. reticulatus Gill & Woodland, P. pictus Gill & Randall, P. tonozukai Gill & Allen, P. jace Allen, Gill & Erdmann and P. stellatus new species. The last-named is herein described from six specimens from Batanta and Batu Hitam in the Raja Ampat Islands, West Papua, Indonesia. It is distinguished from other members of the complex in live coloration, and in having higher mean numbers of scales in lateral series and of anterior lateral-line scales (36-38 and 29-32, respectively), and a deeper body as measured from the dorsal-fin origin to pelvic-fin origin (31.8-33.5 % SL).

Comparative phylogeography of three codistributed stomatopods: origins and timing of regional lineage diversification in the Coral Triangle.

The Indonesian-Australian Archipelago is the center of the world's marine biodiversity. Although many biogeographers have suggested that this region is a "center of origin," criticism of this theory has focused on the absence of processes promoting lineage diversification in the center. In this study we compare patterns of phylogeographic structure and gene flow in three codistributed, ecologically similar Indo-West Pacific stomatopod (mantis shrimp) species. All three taxa show evidence for limited gene flow across the Maluku Sea with deep genetic breaks between populations from Papua and Northern Indonesia, suggesting that limited water transport across the Maluku Sea may limit larval dispersal and gene flow across this region. All three taxa also show moderate to strong genetic structure between populations from Northern and Southern Indonesia, indicating limited gene flow across the Flores and Java Seas. Despite the similarities in phylogeographic structure, results indicate varied ages of the genetic discontinuities, ranging from the middle Pleistocene to the Pliocene. Concordance of genetic structure across multiple taxa combined with temporal discordance suggests that regional genetic structures have arisen from the action of common physical processes operating over extended time periods. The presence in all three species of both intraspecific genetic structure as well as deeply divergent lineages that likely represent cryptic species suggests that these processes may promote lineage diversification within the Indonesian-Australian Archipelago, providing a potential mechanism for the center of origin. Efforts to conserve biodiversity in the Coral Triangle should work to preserve both existing biodiversity as well as the processes creating the biodiversity.

Three new species of Trimma (Pisces; Gobioidei) from Indonesia.

Three new species of Trimma are described from various localities in Indonesia. All three can be readily identified from their live, freshly collected, or preserved colouration. Trimma meranyx n. sp. is further distinguished from other species by the possession of 8-9 scales in the predorsal midline, up to three rows of (usually) cycloid scales on the opercle, two scales at the posterodorsal border of the cheek, a very slightly elongate second dorsal spine which only just reaches the spine or anterior rays of the second dorsal fin, unbranched pectoral fin rays, a fifth pelvic fin ray that branches once and is 64-85% the length of the fourth ray, and a full basal membrane connecting the inner branches of the two fifth pelvic rays. The dark red (live) or black posterior half of the caudal peduncle with large white spots straddling the dorsal and ventral midlines just anterior to the first procurrent caudal fin rays is the diagnostic colour character. The species is known from North Sulawesi, West Papua (Raja Ampat and Fakfak), and the south-eastern tip of Papua New Guinea, with possible records from the Philippines and Vanuatu. Trimma pajama n. sp. has 6 scales in the predorsal midline, two ctenoid scales along the dorsal margin of the opercle, a slightly elongate second dorsal spine reaching posteriorly to the base of the spine or first ray of the second dorsal fin, unbranched pectoral fin rays, a fifth pelvic ray with a single branch point and which is 58-72% the length of the fourth ray, and a full basal membrane connecting the inner branches of the two fifth pelvic rays. The live, freshly collected and preserved colour pattern of alternating dark and light stripes on the head and most of the body (except the posterior half of the caudal peduncle) is diagnostic. It is currently known from West Papua (Raja Ampat and Fakfak) and the southern tip of Papua New Guinea, with possible records from Kalimantan (Indonesia), Palau, the Hermit Is (Papua New Guinea) and the Solomon Islands. Trimma zurae n. sp. has 8-9 scales in the predorsal midline, usually a single row of cycloid scales along the upper border of the opercle, 11 anterior and 9 posterior transverse scale rows, no elongated spines in the first dorsal fin, 9 dorsal and 8 anal fin rays, the middle rays of the pectoral fin branched, a single branch in the fifth pelvic fin ray which is 65-76% the length of the fourth ray and a reduced basal membrane of < 20% the length of the fifth ray. The eye-diameter sized black ocellated spot between the first to fifth spines of the first dorsal fin is diagnostic, as are the pupil-diameter sized orange spots on the nape, opercle and posterodorsal part of the cheek. It is currently known only from a single locality just west of Manado, Sulawesi.