Fig 2 - uploaded by Yoshihisa Fujita
Content may be subject to copyright.
Chirostylus stellaris Osawa, 2007, first zoea. A, lateral; B, carapace, abdomen, and telson, dorsal; C, rostrum, dorsal; D, posterior margin of telson, dorsal. scale bars: a, b = 0.5 mm; c, d = 0.1 mm.
Source publication
T h e c o m p l e t e l a r v a l development of the anomuran chirostylid, Chirostylus stellaris Osawa, 2007, is described and illustrated from laboratory-reared material. This species has two zoeal stages and one megalop. The zoeal phase was completed within 48 hours and the megalopl phase lasted approximately three weeks. The setae on the coxal,...
Context in source publication
Context 1
... cL 1.22 mm. carapace (Fig. 2a, B, c): multispinulate (approximately 62 spines) globose carapace; prominent, extremely long dorsal and lateral spines absent; rostral spine present and spinulate, subequal to antennal protopod in length; anterodorsal and posterodorsal setae absent; ventral margin without setae; eyes ...
Similar publications
Although many lineages of terrestrialized crustaceans have poor olfactory capabilities, crabs in the family Coenobitidae, including the terrestrial hermit crabs in the genus Coenobita , are able to locate food and water using olfactory antennae (antennules) to capture odors from the surrounding air. Terrestrial hermit crabs begin their lives as sma...
Citations
... Abbreviated larval development has been reported in the families Chirostylidae (Clark & Ng 2008;Fujita & Clark 2010), Lomisidae (Cormie 1993;McLaughlin et al. 2010) and some species of Lithodidae (Haynes 1982;Crain & McLaughlin 2000a, b;McLaughlin et al. 2003). Unfortunately, the developmental pattern in the two marine fossil aeglids Haumuriaegla Feldmann 1984 andProtaegla Feldmann et al. 1998 is not known. ...
... In non-aeglid anomurans, pleopods 2-5 are absent (regular development pattern) or present as buds or incompletely developed rudiments (abbreviated development pattern) in the first zoeal instar, that gradually develop to non-functional appendages during larval development, and attain full development to become functional at the megalopal stage (Pike & Wear 1969;Haynes 1982;Stuck & Truesdale 1986;Christiansen & Anger 1990;Brodie & Harvey 2001;Harvey 1992;Cormie 1993;Hernández et al. 2002;Barria et al. 2006;Fujita & Clark 2010;Baba et al. 2011). ...
The present paper contains the complete description of the external morphology of the first juvenile stage of Aegla per-obae analysed through light microscopy (LM) and scanning electron microscopy (SEM). Newly-hatched juveniles were obtained from ovigerous females kept under laboratory conditions. Hatching is asynchronous, taking 2–4 days for all juveniles of a single brood to hatch. Average carapace dimensions are 1.54 mm wide and 1.69 mm long (rostrum excluded). Morphology of the carapace, of the cephalothoracic appendages (antennule, antenna, mandible, maxillule, maxilla, max-illipeds, and pereopods), of the pleon, and of the tail fan (telson plus uropods) are described in detail. Aegla perobae juveniles can be readily differentiate from the first juveniles of other aeglids species described so far by the upwardly curved condition of the distal region of the rostrum and the distinct groove along the orbital sinus produced the elevated free in this area. Pleopods 2–5 are present as rudimentary digitiform buds. Rudimentary pleopods are still present in adult males of the species, a trait not yet described in freshwater aeglids. This curious condition is compared and discussed in the light of the current knowledge of early postembryonic developmental patterns found in other anomurans.
... On the other hand, the ad vanced first zoea of K. tyleri does not have any anomuran hair on the telson , which would place it closer to the Chirostylidae than the Galatheidae (Pike & Wear 1969, Clark & Ng 2008, Baba et al. 2011). It should be noted, however, that the more advanced zoeal stages of the Chirostylidae have only been described for Chirostylus stellaris (Fujita & Clark 2010 ). Knowledge of the morphology of ad vanced chirostylid larvae could present further taxonomic clues to the relatedness with Kiwaidae, in particular with regard to the development of the tail fan in more advanced stages. ...
... Despite the evidence presented appearing compelling, the authors attributed food independence to primitive feeding structures alone, rather than biochemical proof of energy reserves. C. stellaris, which follows a strongly abbreviated larval development of 2 zoeal stages and a megalopa stage, has also been demonstrated to be lecithotrophic in both zoeal stages at least (Fujita & Clark 2010). The level of lecithotrophy observed in the first zoeal stage of K. tyleri is striking; with a C:N ratio ≥11.7, the level of lipid storage is exceptionally high, and higher than the C:N ratio (≥10.5) ...
The deep-sea squat lobster Kiwa tyleri (also known as yeti crab) is the dominant macroinvertebrate inhabiting hydrothermal vents on the northern and southern segments of the East Scotia Ridge in the Southern Ocean. Here, we describe the first zoeal stage of the species—which is morphologically advanced—and provide evidence for its lecithotrophy in development. This morphologically advanced stage at hatching suggests that dispersal potential during early ontogeny may be limited. Adults of K. tyleri typically inhabit a warm-eurythermal, and spatially defined, temperature envelope of vent chimneys. In contrast, ovigerous females with late embryos are found away from these temperatures, off the vent site. This implies that at least part of embryogenesis takes place away from the chemosynthetic environment. Larvae are released into the cold waters of the Southern Ocean that are known to pose physiological limits on the survival
of reptant decapods. Larval lecithotrophy may aid long developmental periods under these conditions and facilitate development independent of pronounced seasonality in primary production. It remains uncertain, however, how population connectivity between distant vent sites may be achieved.
... Distribution ranges are usually geographically confined by limitations imposed by biotic factors such as larval duration, specific niche requirements and behaviours, and abiotic factors such as ocean floor topography, ocean currents, environmental conditions across latitudinal and depth gradients, and historical events such as continental plate movements (Brown et al. 1996; Gaston 1998). The complete larval duration is known for only four species, Galathea intermedia (Christiansen and Anger 1990), Sadayoshia tenuirostris (Fujita and Shokita 2005 ), Munida gregaria (Barros et al. 2007) and Chirostylus stellaris (Fujita and Clark 2010). Studies on the first zoeal stage for 11 other species clearly indicate differences across genera of both superfamilies (Baba et al. 2011, this volume). ...
Knowledge of squat lobster diversity has grown rapidly during the past two decades and has now reached a level where it is possible to attempt a biogeographic synthesis. Squat lobsters of the superfamilies Galatheoidea and Chirostyloidea are now represented by more than 1000 species world-wide (10% undescribed) across nearly all latitudes and depths; the potential for new species discoveries remains high. Patterns of global species richness indicate a distinct global centre of diversity in the tropical western Pacific from between New Caledonia, Indonesia and the Philippines, with progressively fewer species recorded with increasing distance from this centre. This pattern holds for taxa in both superfamilies and across all depths, although a single unified centre of diversity is less obvious for lower slope and abyssal species (>2000 m) compared with their shallow-water relatives.
The complete mitochondrial genome (mitogenome) contributed crucial information, which could improve the better understanding of molecular phylogenetic analysis, evolution, and gene rearrangements. However, only a few Coenobitidae and Albuneidae mitogenomes have been described, and controversies about the Anomuran phylogeny remain. Here, we determined three Coenobitidae species (Coenobita perlatus, Coenobita rugosus, Coenobita clypeatus) and one Albuneidae species (Emerita talpoida). As the representative species of genera or families, and even the first species of the genus, supplementing these four species is essential to study the phylogenetic relationships within Anomura. Most of the four novel mitogenomes have the typical 37 genes, except for E. talpoida, which lacked trnF. Through combining these new data with 31 Anomuran mitogenomes from Genbank, different gene rearrangement patterns and internal phylogenetic relationships of Anomura were investigated. In our phylogeny analysis, all the Anomuran species were clustered into one group, and the polyphyly of Paguroidea was well supported. Moreover, various peculiar mitochondrial gene orders (MGOs) were summarized among Anomura and preliminary determined their rearrangement mechanisms through CREx. Twenty different MGOs were suggested in our research, and we were focused seven MGO patterns (Pattern A-J) in the process of discussing the gene rearrangement mechanism. Currently making full use of the large taxon sampling, our results provide valuable information on the evolutionary status of Anomuran species and are available for systematic rearrangement and phylogenetic analyses.
The family Aeglidae
comprises three genera, one extant (Aegla) and two extinct genera (Protaegla and Haumuriaegla), the latter two genera are known only from fossils from marine sediments (indicating a marine origin for the group). Aegla contains all extant species and constitutes a monophyletic group within the Anomura. All 78 species and subspecies described so far are entirely adapted to freshwater habitats and are endemic to temperate and subtropical regions of continental South America. While most species are found in epigean habitats, there are a few cave-dwelling species in southeastern Brazil. The reproductive period varies from 8 to 12 months (in species from colder higher latitudes), to 4–7 months (in species from lower latitudes where warm-rainy and cold-dry seasons alternate). The adult males of seasonally breeding species include two morphotypes, one non-reproductive and the other reproductive. Eggs are large and few in number, and post-embryonic development is epimorphic. Juveniles have limited dispersal capacity and recruits tend to remain with the parental population. Aegla is the most severely threatened group among South American freshwater decapods because of habitat degradation, high endemism, a restricted area of occupancy, and a severely fragmented spatial distribution with reproductively isolated subpopulations.
