Anchialine Research Articles

A new Speleophria (Copepoda, Misophrioida) from an anchialine cave of the Yucatán Peninsula with comments on the biogeography of the genus

Misophrioid copepods are hyperbenthic or anchialine forms whose known distributional patterns appear to have a Tethyan origin and subsequent vicariant processes. A new misophrioid copepod, Speleophria germanyanezi n. sp., collected from an anchialine cave in Cozumel Island, Yucatan Peninsula (YP), is described based on male and female specimens. This is the second report describing a misophrioid copepod species from the Yucatan Peninsula, harboring a remarkably diverse anchialine crustacean fauna. The new species is the sixth of this anchialine genus. It differs from its congeners by a combination of characters including: the armature of leg 4 exopod, 21-segmented female antennule, 24-segmented male antennule, both with moderate proximal expansion, the male with the terminal antennulary segments distinctively elongate. The fifth leg distal segment is armed with 3 elements in the female, 4 in the male. The female genital double-somite is furnished with long, slender spinules. The other members of Speleophria are distributed in Europe (Croatia, Spain), Bermuda, and Australia. Relationships among species of Speleophria have revealed amphiatlantic pairs of sister taxa. The new species has little affinity with its regionally closest congener from Bermuda; it appears to be most closely related to the Croatian S. mestrovi and could be its western Atlantic counterpart. The different misophrioid fauna between the YP and Cozumel Island and the more recent emergence of Cozumel with respect to that of the YP plate suggests either an ancestral Tethyan-related independent colonization or a relatively recent local dispersal through deep-sea crevicular habitats before emergence of these land masses.

Phylogenetic evidence that both ancient vicariance and dispersal have contributed to the biogeographic patterns of anchialine cave shrimps

Cave shrimps from the genera Typhlatya, Stygiocaris and Typhlopatsa (Atyidae) are restricted to specialised coastal subterranean habitats or nearby freshwaters and have a highly disconnected distribution (Eastern Pacific, Caribbean, Atlantic, Mediterranean, Madagascar, Australia). The combination of a wide distribution and a limited dispersal potential suggests a large-scale process has generated this geographic pattern. Tectonic plates that fragment ancestral ranges (vicariance) has often been assumed to cause this process, with the biota as passive passengers on continental blocks. The ancestors of these cave shrimps are believed to have inhabited the ancient Tethys Sea, with three particular geological events hypothesised to have led to their isolation and divergence; (1) the opening of the Atlantic Ocean, (2) the breakup of Gondwana, and (3) the closure of the Tethys Seaway. We test the relative contribution of vicariance and dispersal in the evolutionary history of this group using mitochondrial genomes to reconstruct phylogenetic and biogeographic scenarios with fossil-based calibrations. Given that the Australia/Madagascar shrimp divergence postdates the Gondwanan breakup, our results suggest both vicariance (the Atlantic opening) and dispersal. The Tethys closure appears not to have been influential, however we hypothesise that changing marine currents had an important early influence on their biogeography.

Xibalbanus cozumelensis, a new species of Remipedia (Crustacea) from Cozumel, Mexico, and a molecular phylogeny of Xibalbanus on the Yucatán Peninsula

A new species belonging to the crustacean class Remipedia is described from an anchialine cave system on the island of Cozumel (Mexico), and is illustrated and compared morphologically and molecularly (CO1 and 16S) with closely related taxa. Xibalbanus cozumelensis sp. nov., the first remipede described from Cozumel, is morphologically similar to Xibalbanus tulumensis (Yager, 1987) from the Yucatán Peninsula, but the two species are genetically separate from each other (about 10% in CO1). A phylogenetic (Bayesian) analysis of Yucatán remipede populations based on CO1 and 16S placed them in a monophyletic Xibalbanus (in Xibalbanidae fam. nov.), with X. cozumelensis as most closely related to X. tulumensis. The Yucatán Peninsula and Cozumel have been separate since approx. early Cenozoic (~65 Ma), which suggests allopatric speciation for X. cozumelensis sp. nov. and X. tulumensis. However, the comparatively low genetic divergence between the two species may indicate that there has been gene flow between ‘mainland’ Yucatán and Cozumel long after the geological separation of the two landmasses, e.g., in cave systems under the sea bed, either continuously or sporadically, for example during the Last Glacial Maximum when the sea level was about 120 m lower than today.

A new anchialine species of Naushonia (Decapoda: Gebiidea: Laomediidae) from the Bahamas.

A new species of mud shrimp of the genus Naushonia Kingsley, 1897 is described from two anchialine caves on the island of Great Abaco in the Bahamas. Naushonia tinkeri n. sp. is the fifteenth species in the genus and the second to be described from the Bahamas. The new species is morphologically similar to N. augudrea (Juarrero & García, 1997) from Holguín Province, eastern Cuba, with which it shares a carapace with cervical and cardiac grooves; however, it can be distinguished by having a pigmented cornea, the first pereiopod with a proportionately longer propodus and dactylus without a toothed external margin, and the telson longer relative to the uropod length. The new species inhabits anchialine caves and is the largest one reported until now.

A new anchialine Stephos Scott from the Yucatan Peninsula with notes on the biogeography and diversity of the genus (Copepoda, Calanoida, Stephidae).

Surveys of the anchialine crustacean fauna of the Yucatan Peninsula (YP), Mexico, have revealed the occurrence of calanoid copepods. The genus Stephos Scott, 1892, belonging to the family Stephidae is among the most frequent and widely distributed groups in anchialine caves but has not been hitherto recorded from the YP. Recent collections from an anchialine cave in an island off the northern coast of the YP yielded many specimens of a new species of Stephos. The new taxon, S. fernandoi sp. n., is described here based on male and female specimens. The new species is clearly distinguished from its congeners by the following characters: male left fifth leg with three terminal lamellae plus subdistal process, right leg with distal row of peg-like elements; female fifth leg with single long, acute apical process; genital double-somite with two rows each of 4 long spinules adjacent to operculum; legs 2-4 with articulated setae. The diversity of the genus shows regional differences; the Australia-Western Pacific region is the most diverse (eleven species), followed by the Mediterranean (seven species) and the Northeastern Atlantic (six species); only four species are known from the Northwestern Tropical Atlantic (NWTA). The morphology of the female fifth leg was examined to explore possible biogeographic trends in the genus; patterns suggest multiple colonization events in the highly diverse regions and a relatively recent radiation in the NWTA, characterized by anchialine forms. The introduction of stephid copepods in the region may be a relatively recent event derived from colonization of benthopelagic ancestral forms and subsequent invasion onto cave habitats. The new species appears to be linked to the strictly anchialine Miostephos.

Effects of invasion at two trophic levels on diet, body condition, and population size structure of Hawaiian red shrimp

AbstractWe examined the degree to which invasion by non‐native, nitrogen (N)‐fixing riparian trees and poeciliid fish alters diet of a common grazer/detritivore in brackish ponds on the dry coast of Hawai‛i Island. Because this shrimp, Halocaridina rubra (ʻōpaeʻula), displays a preference for autotrophic components of epilithon, we hypothesized that tree canopy would reduce their body condition and abundance, but that this would be moderated by nutrient quality of leaf litter (high‐quality, non‐native, nitrogen‐fixing tree vs. low‐quality, endemic non‐nitrogen‐fixing tree). We hypothesized that poeciliid invasion would reduce population size and body condition of H. rubra by direct predation and by inducing reductions in feeding rate. Analysis of stable isotopes (δD, δ13C, and δ15N) showed that direct consumption of leaf litter detritus supplemented H. rubra diet in ponds with canopy cover. In addition, epilithon in ponds with canopy cover was isotopically more similar to leaf litter than epilithon in ponds without canopy cover, and our evidence suggests this may be due to contributions of allochthonous nutrient sources to epilithon assemblages. However, canopy cover, whether native or invasive, did not decrease epilithon growth rates and had little effect on shrimp body condition or population size. In contrast, poeciliid invasion reduced daylight grazing on the benthos, and caused a reduction in body condition among larger shrimp. Our results indicate that primary succession by invasive trees may shift food web linkages in these ponds from autotrophic to heterotrophic support, without negative impacts on native grazer/detritivore communities. We suggest that poeciliid invasions have sub‐lethal effects on H. rubra as well as their direct predation effects, with potential long‐term implications for the ecosystem function of anchialine ponds and other coastal systems.

Genetic spatial structure of an anchialine cave annelid indicates connectivity within - but not between - islands of the Great Bahama Bank

Land-locked anchialine blue holes are karstic sinkholes and caves with tidally influenced, vertically stratified water bodies that harbor endemic fauna exhibiting variable troglomorphic features. These habitats represent island-like systems, which can serve to elucidate evolutionary and biogeographic processes at local scales. We investigated whether the ‘continuous spelean corridor’ hypothesis may elucidate the biogeographical distributions of the stygobitic annelid Pelagomacellicephala iliffei (Polynoidae) collected from the Great Bahama and Caicos Banks of the Bahamas Archipelago. Phylogenetic reconstructions were performed using Bayesian Inference on individual and combined datasets of three molecular markers (16S rDNA, COI, 18S rDNA) and species delimitation employed three widely accepted methods in DNA taxonomy, namely GMYC, bPTP, and ABGD. Mantel tests were used to test the effect of geography on genetic structure. Using these analyses, we recovered five independently evolving entities of the focal species across four islands of the Great Bahama Bank including Cat, Eleuthera, Exumas, and Long. Genetic data yielded strong correlations between islands and phylogenetic entities, signifying independent evolutionary histories within anchialine caves across the platform. The island of Eleuthera showed intra-island gene flow and dispersal capabilities between blue holes separated by 115km, providing evidence of a crevicular spelean corridor within the island. However, no evidence of inter-island dispersal is present in the analyzed system. Consistent with previous biogeographic studies of cave crustaceans, the major barriers shaping the cave biota of the Bahamas Archipelago appears to be the deep trenches and channels separating the Bahamian banks.

Three Species of <i>Grandidierella </i>(Crustacea: Amphipoda: Aoridae) from Coastal Areas of the Tohoku and Kanto-Tokai Districts, East Japan, with the Description of Two New Species

Three species of Grandidierella (Crustacea: Amphipoda: Aoridae) were collected from coastal areas of the Tohoku and Kanto-Tokai Districts, East Japan. The first species is G. sanrikuensis sp. nov. from Miyagi Prefecture, which is characterized by the male gnathopod 1 with carpus bearing 3 teeth (only middle tooth large). The second species is G. rubroantennata sp. nov. from Chiba Prefecture. This new species is identical with G. insulae sensu Ariyama (1996) , but is different from the true G. insulae Myers, 1981 in the more flagellar articles of the antennae. The last species is G. osakaensis Ariyama, 1996 , from river mouths in Kanagawa and Shizuoka Prefectures and an anchialine pool in Izu Oshima Island, Tokyo Prefecture. This species can inhabit various sandy mud bottoms in a brackish environment. Including G. japonica Stephensen, 1938, four Grandidierella species occur in the districts.

Anchialocarididae, a new family of anchialine decapods and a new species of the genus Agostocaris from Cozumel Island, Mexico

Two new species of anchialine cave shrimp from Cozumel Island are described. A new species from the family Agostocarididae, Agostocaris zabaletai n. sp., occurs in three cenotes on the island (Chempita, Chankanaab System and Tres Potrillos). This new species is closely related to Agostocaris bozanici that is known from one isolated cenote in another zone of the island. Agostocaris zabaletai n. sp. is similar to A. bozanici because it lacks a rostrum with teeth, and the palp of the first maxilliped is not segmented. In addition A. zabaletai also differs from A. bozanici by bearing four pairs of spines on the telson and only one spine on the outer ramus of the uropods. Both Agostocaris williamsi and Agostocaris acklinsensis differ from A. zabaletai because both species have occasionally a serrate rostrum, and these species are reported exclusively from the Bahamas. A new family, Anchialocarididae, new genus and species Anchialocaris paulini n. sp. are described. This new species is known exclusively from the cenote Chempita located in the central area of the island. The new family Anchialocarididae is closely related to the families Agostocarididae and Atyidae because they have a similar branchial formulae. The main difference is that the new family has a simple articulation between carpus and palm of the first pereiopod, and this appendage is more slender than the second. Although the new family has several setae on the rudimentary propodus on the second pereiopod it lacks the abundance of setae found in other members of the Atyidae family genus Typhlatya. The relationship between this new family and the Agostocarididae is discussed.

Mexican anchialine fauna — With emphasis in the high biodiversity cave El Aerolito

Anchialine ecosystems are one of the least studied in the world since they are very difficult to access, their bibliography is scant and widely scattered, and studies rarely specify actual locations. Mexico is one of the richest countries for these ecosystems, as it has a huge number of cenotes (sinkholes) just in the Yucatan Peninsula. Here we present a thorough checklist of all the species occurring at El Aerolito cave system, Cozumel, Quintana Roo, which has been identified as one of the richest and most biodiverse of the world. Indeed, it holds 100 species (53 as new records), classified within 10 phyla, from which Porifera, Echinodermata and Annelida are the richest groups in contrast with the rest of the subaquatic caves in the world where the dominant phylum is Arthropoda. An exhaustive review of all anchialine Mexican fauna is presented as context, which includes records dating as far back to 1938, half of them just from the last decade. Total records add up to 335, including 47 common names and uncertain records, classified into 171 operational taxonomic units, 108 identified to species level, 33 of which are endemic to cave environments (stygobite), while another 30 species are presumed stygobites. Half of the Mexican anchialine cave systems have records for only one to three species, five have more than 10 records, while only three anchialine cave systems include representatives of more than two phyla. Unfortunately, and despite the scarce information, 12 of the species enlisted are already cataloged in some extinction category by the current national regulation (NOM-059) or on the Red List of the IUCN. Nine of them are in the highest categories of concern, calling for further understanding about these ecosystems in order to develop effective regulations and concurrent management programs for their protection.

Draft Genome Sequence of Terasakiispira papahanaumokuakeensis PH27AT, a Spiral Bacterium from the Northwestern Hawaiian Islands.

The genus Terasakiispira hosts only Terasakiispira papahanaumokuakeensis PH27AT, cultivated from an anchialine pond on Pearl and Hermes Atoll, Northwestern Hawaiian Islands. The strain’s genome sequence may provide insights into the evolution of free-living Oceanospirillaceae.

World Register of marine Cave Species (WoRCS): a new Thematic Species Database for marine and anchialine cave biodiversity

Scientific exploration of marine cave environments and anchialine ecosystems over recent decades has led to outstanding discoveries of novel taxa, increasing our knowledge of biodiversity. However, biological research on underwater caves has taken place only in a few areas of the world and relevant information remains fragmented in isolated publications and databases. This fragmentation makes assessing the conservation status of marine cave species especially problematic, and this issue should be addressed urgently given the stresses resulting from planned and rampant development in the coastal zone worldwide. The goal of the World Register of marine Cave Species (WoRCS) initiative is to create a comprehensive taxonomic and ecological database of known species from marine caves and anchialine systems worldwide and to present this as a Thematic Species Database (TSD) of the World Register of marine Species (WoRMS). WoRCS will incorporate ecological data (e.g., type of environment, salinity regimes, and cave zone) as well as geographical information on the distribution of species in cave and anchialine environments. Biodiversity data will be progressively assembled from individual database sources at regional, national or local levels, as well as from literature sources (estimate: >20,000 existing records of cave-dwelling species scattered in several databases). Information will be organized in the WoRCS database following a standard glossary based on existing terminology. Cave-related information will be managed by the WoRCS thematic editors with all data dynamically linked to WoRMS and its team of taxonomic editors. In order to mobilize data into global biogeographic databases, a Gazetteer of the Marine and Anchialine Caves of the World will be established. The presence records of species could be eventually georeferenced for submission to the Ocean Biogeographic Information System (OBIS) and constitute an important dataset for biogeographical and climate change studies on marine caves and anchialine systems

Evolution of cave suspension feeding in Protodrilidae (Annelida)

Protodrilidae belongs in a lineage that until now entirely consisted of deposit‐feeding, highly adapted interstitial annelids. Except for a pair of anterior palps, all protodrilids lack appendages, parapodia and chaetae; and have slender bodies adapted to glide between the sand grains by ciliary motion. The first exception to these characteristics is Megadrilus pelagicus n. sp. inhabiting the water column of the anchialine La Corona cave system in Lanzarote. Its morphology and evolutionary history are here investigated by combining observations from in vivo video recordings and advanced microscopy with phylogenetic analyses. Our studies revealed a unique pelagic, suspension feeding behaviour attained by its long ciliated palps in combination with an autopomorphic dorsal ciliated keel and several longitudinal and transverse ciliary bands. Phylogenetic analyses recovered Megadrilus pelagicus n. sp. nested within Protodrilidae indicating that its unique traits are derived within the family. These traits are traced in the tree topologies in correlation to cave colonization. The evolution of these traits can be functionally explained by the different demands of a pelagic suspension feeding strategy compared to the ancestral deposit‐feeding guild of the family. The origin of this suspension feeding strategy was presumably favoured by the partial isolation of the anchialine ecosystem, connected to the sea only through the highly porous volcanic subterranean bedrock. This crevicular connection limits the amount of predators and turbulence in the cave, but allows continuous water flow into the system carrying organic particles, which is the main source of food when photosynthetic primary production does not occur and sedimentation is limited. These conditions may select for pelagic suspension feeding as the most feasible life‐strategy in anchialine caves, which the dominance of pelagic, suspension feeding crustaceans and annelids in anchialine cave assemblages may also reflect. For species of ancestrally deposit‐feeding lineages entering the cave system, such as the annelid families Protodrilidae and Nerillidae, an adaptive‐shift from interstitial to crevicular habitats seemingly correlates with dramatic morphological changes and speciation. The dramatic changes observed in these primarily interstitial lineages compared to their relatives, point to alternative adaptive evolutionary pathways related to ecological fitness contrary to the previously proposed theories focusing on geological or stochastic processes.

Changes in segmentation and setation along the anterior/posterior axis of the homonomous trunk limbs of a remipede (Crustacea, Arthropoda).

This study describes the segmentation and setation at different developmental stages of the homonomous trunk limbs of the remipede Speleonectes tulumensis Yager, 1987 collected in anchialine caves of the Yucatan Peninsula. Most homonomous trunk limbs originate ventrolaterally and are composed of two protopodal segments, three exopodal segments and four endopodal segments; contralateral limb pairs are united by a sternal bar. However, the last few posterior limbs originate ventrally, are smaller sized, and have regressively fewer segments, suggesting that limb development passes through several intermediate steps beginning with a limb bud. A terminal stage of development is proposed for specimens on which the posterior somite bears a simple bilobate limb bud, and the adjacent somite bears a limb with a protopod comprised of a coxapod and basipod, and with three exopodal and four endopodal segments. On each trunk limb there are 20 serially homologous groups of setae, and the numbers of setae on different limbs usually varies. These groups of setae are arranged linearly and are identified based on the morphology of the setae and their position on the segments. The number of setae in these groups increases gradually from the anterior homonomous limb to a maximum between limbs 8–12; the number then decreases sharply on the more posterior limbs. Changes in the number of setae, which reach a maximum between trunk limbs 8–12, differ from changes in segmentation which vary only over the last few posterior trunk limbs. Following a vector analysis that identified a spatial pattern for these 20 groups of setae among the different homonomous limbs, the hypothesis was confirmed that the number of setae in any given group and any given limb is correlated with the group, with the position of the somite along the body axis, and with the number of somites present on the specimens. This is the first vector analysis used to analyze a pattern of developmental changes in serially homologs of an arthropod. Development of remipede limbs are compared and contrasted with similar copepod limbs. Architecture, particularly the sternal bar uniting contralateral limb pairs, proposed as homologous, and development of trunk limb segmentation of the remipede is generally similar to that of copepods, but the remipede limb differs in several ways including an additional endopodal segment, the proximal, that appears simultaneously with the protopod during development.

A new species of the genus Melita (Amphipoda, Hadzioidea, Melitidae) from anchialine pool on the Cozumel Island, NE Caribbean Sea.

A new species of genus Melita collected from anchialine pool (Cenote Aerolito) on Cozumel Island is described. Distinctive characters of male of the new species include an accessory flagellum 4-articulate; palm of gnathopod 2 with long setae; urosomite 2 with two robust setae on right side, and one on left. Female of the new species differs by coxa 6 without lateral ridge at base of hook, and anteroventral angle without stridulating ridges on anteroventral process; gnathopods 1-2 covered with long setae on articles 5-6. The main morphological differences between males of Melita species recorded previously for the Gulf of Mexico and the Caribbean Sea and the new species are also given.

Nutrient and Organic Matter Inputs to Hawaiian Anchialine Ponds: Influences of N-Fixing and Non-N-Fixing Trees

Invasive nitrogen-fixing plants often increase energy and nutrient inputs to both terrestrial and aquatic ecosystems via litterfall, and these effects may be more pronounced in areas lacking native N2-fixers. We examined organic matter and nutrient inputs to and around anchialine ponds on Hawai‘i Island's leeward coast from an invasive, N2-fixing tree, Prosopis pallida, and a non-N2-fixing tree, Thespesia populnea. On a monthly basis we quantified: (1) tree basal area and stem density surrounding the ponds, and (2) nutrient content and quantity of P. pallida and T. populnea litter inputs. Tree density and basal area significantly predicted litterfall mass inputs for both species, but there was no difference in mean total annual litterfall mass, foliar N concentration, or litterfall N between the pond types. Time did not significantly influence litterfall mass, C, or P but did affect litterfall N, likely due to the production of P. pallida pods. In contrast, P concentrations were three times greater in T. populnea litter than in P. pallida litter, resulting in significantly higher P deposition where T. populnea was the prevalent tree species. Because this deposition of labile P by the non-N2-fixing T. populnea has the potential to strongly influence water quality and soil chemistry, its replacement by P. pallida in tree communities of lowland Hawai‘i may alter the functioning of anchialine pond ecosystems.

A new species of Speleophriopsis (Copepoda: Misophrioida) from an anchialine cave in the Adriatic Sea, Mediterranean

A new copepod species, Speleophriopsis mljetensis, collected from an anchialine cave Bjejajka on Mljet Island (Croatia) is described. The prosome of the new species is 5-segmented; the urosome has five somites in females and six in males; the genital double-somite is symmetrical and is longer than wide; the caudal rami are symmetrical, with seta I well developed; the antennules of both sexes are 27-segmented and symmetrical; the antennal exopod is 7-segmented; the maxillule possesses 15 armature elements on the praecoxal arthrite and the proximal basal endite has three slender setae and one stout claw-like seta, the fifth legs are symmetrical, 4-segmented and uniramous, and the distal segment is elongate and armed with seven and six elements in males and females, respectively. Speleophriopsis mljetensis is comparated with similar species S. balearicus and S. canariensis. The new species is mainly distinguished by the armature of the genital operculum, the fifth legs of both sexes, maxilliped distal segment armature and total length of both sexes. This is the second report of a speleophriid copepod, otherwise thought to be a Tethyan relict, from an Adriatic anchialine cave. In the Bjejajka Cave, the salinity varied between 1.5 at the surface to 39 psu at the bottom, and the temperature ranged between 14.2 and 16.6 °C. It might be assumed that it colonised Bjejajka anchialine cave from its natural deep-sea habitat. However, the distributions of speleophriids in the Mediterranean are difficult to explain; therefore, this finding is of particular importance, contributing to our knowledge of the global biogeography of these Tethyan relicts.

Life in the Underworld: Anchialine cave biology in the era of speleogenomics

Anchialine caves contain haline bodies of water with underground connections to the ocean and limited exposure to open air. Despite being found on islands and peninsular coastlines around the world, the isolation of anchialine systems has facilitated the evolution of high levels of endemism among their inhabitants. The unique characteristics of anchialine caves and of their predominantly crustacean biodiversity nominate them as particularly interesting study subjects for evolutionary biology. However, there is presently a distinct scarcity of modern molecular methods being employed in the study of anchialine cave ecosystems. The use of current and emerging molecular techniques, e.g., next-generation sequencing (NGS), bestows an exceptional opportunity to answer a variety of long-standing questions pertaining to the realms of speciation, biogeography, population genetics, and evolution, as well as the emergence of extraordinary morphological and physiological adaptations to these unique environments. The integration of NGS methodologies with traditional taxonomic and ecological methods will help elucidate the unique characteristics and evolutionary history of anchialine cave fauna, and thus the significance of their conservation in face of current and future anthropogenic threats. Here we review previous contributions to our understanding of anchialine biodiversity and evolution, and discuss the potential of speleogenomic methods for future research in these threatened systems.

A new species of Atergopedia (Copepoda: Harpacticoida: Novocriniidae) from a Caribbean mesophotic reef

Coordinated research efforts in mesophotic coral reefs are only a decade old, but have already produced exciting findings in ecology, physiology, geomorphology, population genetics, biodiversity, and taxonomy. In this taxonomic contribution, we describe both sexes of a new copepod species of the family Novocriniidae Huys and Iliffe in Zool Scr 27(1):1–15, 1998 from a mesophotic coral reef off southwestern Puerto Rico. This is only the fifth species of the family and the fourth of the genus Atergopedia Martinez Arbizu and Moura in Zool Beitr NF 38:189–210, 1998. The new species, Atergopedia dowgialli sp. nov., shares the following characters with its three congeners: 1) antenna without seta on the first endopodal segment; 2) lateral armature of the female antenna shows a multiplication of distinct setae and consists of one geniculate seta followed by five or more slender setae; 3) the first endopod segment of the first swimming leg P1 bears no inner seta; 4) male fifth leg with two spines on endopodal lobe; and 5) the exopod of the fifth swimming leg fused to basendopod in the female. Atergopedia dowgialli sp. nov. is characterized by the loss of the basal seta in both antenna and maxilliped, the loss of the first maxilla endite, the presence of a long process between the outer and distal elements of the leg 1 exopodite 3, which is stronger and longer in the female, and the possession of a very short and strongly ornamented furca in both sexes. The genus Atergopedia has been found in deep and relatively shallow habitats from the Arctic Ocean to the Caribbean. In contrast, almost all species of the taxon Novocrinidimorpha, which includes the families Novocriniidae, Superornatiremidae Huys 1996, and Rotundiclipeidae Huys 1988, have been found associated with anchialine caves, indicating a derived distribution for Atergopedia.

Glyphosate herbicide toxicity to native Hawaiian macroalgal and seagrass species

Glyphosate-based herbicides are commonly used to combat weeds and unwanted grasses in many habitats in the Hawaiian Islands, including near freshwater, marine, and anchialine pond shorelines. Glyphosate is reported to degrade within a few days of application and to break down rapidly in soil, which suggests that it is safe for use near aquatic environments. However, glyphosate can be transported to coastal waters, especially during run-off events. Five native macroalgael and seagrass species and one introduced aquatic vascular plant found in coastal anchialine ponds or in the adjacent intertidal zone were exposed to freshly mixed solutions of a glyphosate-based herbicide in lab experiments. Chlorophyll absorbance and photosystem II (PSII) efficiency were measured after 5 to 7 days of incubation. At herbicide concentrations (0.225 to 1.8 g L−1 glyphosate) below the manufacturer’s lowest recommended concentration (3.6 g L−1 glyphosate), chlorophyll absorbance and PSII efficiency differed significantly from the control (0.0 g L−1 glyphosate). Native macroalgae and seagrasses in marine and anchialine aquatic habitats may be negatively affected by use of glyphosate herbicides to control shoreline weeds.