ArticlePDF Available

The effect of temperature and salinity on the larval development of Stenorhynchus seticornis (Brachyura: Inachidae) reared in the laboratory

Authors:
  • Universidad de Oriente Núcleo de Nueva Esparta, Venezuela

Abstract and Figures

Larvae of Stenorhynchus seticornis were reared in the laboratory in a factorial experiment employing three temperatures (22, 25 and 28°C) and three salinities (30, 35 and 40‰) to determine the effects of these variables on the survival and duration of the larval stages. Larvae from five females were subdivided in six groups of 10 and reared in glass bowls containing 125 ml filtered and UV-irradiated seawater at different temperature–salinity combinations. Larvae were transferred daily to clean bowls with newly hatched Artemia nauplii, and the number of moults and mortality within each bowl was recorded. Complete larval development of S. seticornis occurred under all experimental conditions, except at temperature 28°C and salinity 35‰. Salinity affected percentage survival of the two zoeal stages, but not that of the megalopa. Survival of the second zoeal stage, the megalopa, and the complete development to the first crab was affected by temperature, with the greatest survival occurring at 25°C. Duration of the two zoeal stages, the megalopa, and development to the first crab stage showed a gradual reduction with increasing temperature. Development from hatching to the first crab stage required 17 to 31 days and was inversely related to temperature, averaging 26.9 days at 22°C, 21.0 days at 25°C and 19.7 days at 28°C. Salinity affected the duration of the first zoeal stage only.
Content may be subject to copyright.
The effect of temperature and salinity on
the larval development of Stenorhynchus
seticornis (Brachyura: Inachidae) reared
in the laboratory
jesu
s e. herna
ndez
1
, jose
luis palazo
n-ferna
ndez
2
, gonzalo herna
ndez
1
and juan bolan
~
os
1
1
Universidad de Oriente, Escuela de Ciencias Aplicadas del Mar, Boca del
´
o, Isla de Margarita, Venezuela,
2
Universidad de
Oriente, Instituto de Investigaciones Cientı
´
ficas, Boca del
´
o, Isla de Margarita, Venezuela
Larvae of Stenorhynchus seticornis were reared in the laboratory in a factorial experiment employing three temperatures (22,
25 and 288C) and three salinities (30, 35 and 40‰) to determine the effects of these variables on the survival and duration of
the larval stages. Larvae from five females were subdivided in six groups of 10 and reared in glass bowls containing 125 ml
filtered and UV-irradiated seawater at different temperaturesalinity combinations. Larvae were transferred daily to clean
bowls with newly hatched Artemia nauplii, and the number of moults and mortality within each bowl was recorded.
Complete larval development of S. seticornis occurred under all experimental conditions, except at temperature 288C and
salinity 35‰. Salinity affected percentage survival of the two zoeal stages, but not that of the megalopa. Survival of the
second zoeal stage, the megalopa, and the complete development to the first crab was affected by temperature, with the greatest
survival occurring at 258C. Duration of the two zoeal stages, the megalopa, and development to the first crab stage showed a
gradual reduction with increasing temperature. Development from hatching to the first crab stage required 17 to 31 days and
was inversely related to temperature, averaging 26.9 days at 228C, 21.0 days at 258C and 19.7 days at 288C. Salinity affected
the duration of the first zoeal stage only.
Keywords: larval development, temperature, salinity, Stenorhynchus seticornis
Submitted 9 June 2009; accepted 8 March 2010; first published online 5 July 2010
INTRODUCTION
In recent years, the marine ornamental industry has experi-
enced exponential growth which has created a high demand
for many species of fish, corals and crustaceans. The marine
ornamental industry relies heavily on wil d-collected speci-
mens, mainly from coral reefs. This, combined with the preva-
lence of destructive harvesting techniques, has increased
anthropogenic pressure on these fragile ecosystems (see
Rhyne et al., 2005 for references).
Along with corals, marine tropical decapod crustacean s are
among the most popular invertebrate species in the aquarium
trade industry (Calado et al., 2003). In recent years, research-
ers have begun a worldwide effort to minimize the growing
pressure on natural populations of marine ornamental
species and to promot e the sustainable use of these highly
valued resources (Corbin, 2001). Nevertheless, this goal will
only be achieved if wild specimen collection is significantly
replaced by the artificial rearing of these species (Calado
et al., 2003). Aquaculture is thus a viable long-term alternative
to wild collection , allowing the aquarium trade’s future to
become independent from natural resources (Lin & Shi,
2002; Rhyne et al., 2005), and minimizing the negative
impacts on the natural environment (Lin & Shi, 200 2).
Studies on the larval development of decapod crustaceans
have received great attention because they provide not only
valuable information on the larval morphology that helps in
the identification and general classification of larvae and
species, but provide knowledge on the effects of environ-
mental factors such as temperature, salinity, water quality,
antibiotics, culture systems, feeding, etc. on the larval develop-
ment of species with biological and/or economic interests
(Boschi & Scelzo, 1969; Bolan
˜
os, 1992; Nagaraj, 1992;
Gonc¸alves et al., 1995). Raising larvae to juveniles also
provides opportunities for detailed studies in physiology,
biochemistry, genetics and behaviour (Sastry, 1970).
Early stages of development are the most sensitive phase in
the complex life cycle of marine invertebrates, and to maxi-
mize their survival, larvae should be reared close to optimal
conditions (Zacharia & Kakati, 2004). Defining these
optimal conditions for culture of euryhaline marine species
is fundamental to develop optimal rearing protocols for
these species (Sastry, 1970; Zacharia & Kakati, 2004).
Larval development in Crustacea occurs within a well
defined range of environmental conditions characteristic to
a species. Of the environmental factors that affect crustacean
development, temperature and salinity have received great
Corresponding author:
J.L. Palazo
´
n-Ferna
´
ndez
Emails: juis.palazon@icman.csic.es; jose.palazon@ne.udo.edu.ve
505
Journal of the Marine Biological Association of the United Kingdom, 2012, 92(3), 505513. # Marine Biological Association of the United Kingdom, 2010
doi:10.1017/S0025315410000809
attention because they significantly affect survival and the
extent of larval life (Costlow & Bookhout, 1968; Hicks,
1973; Anger, 1983; Gonc¸alves et al., 1995; La
´
rez et al., 2000;
Li & Hong, 2007). Differences in tolerance to these factors
have been observed depending, in part, on the stage of devel-
opment, the species and its habitat (Dı
´
az & Bevilacqua, 1986).
Within a tolerated range, temperature mostly affects dur-
ation of larval stages, and these in turn affect dispersal and
gene flow interacting with coastal physical processes (Crisp,
1976). Salinity influences many physiological functions and
is therefore important in regulating the distribution of estuar-
ine and marine organisms (Ehlinger & Tankersley, 2004).
Larval survival is thus strongly affected by temperature and
salinity (Sandifer, 1973; Paula et al., 2001) although each
species tolerance will be specific for its degree of adaptation
to the environmental gradients of coastal systems (Paula
et al., 2003).
In the field, environmental factors such as temperature and
salinity frequently affect organisms in an interactive way.
Therefore, it is important to investigate responses to the com-
bined effects of temperature and salinity in order to under-
stand, at least in part, the significance of these factors on
survival during early larval development and the problems
involved in recruitment in the natural enviro nment, as well
as the possibility of its successful culture (Mene et al., 1991;
Zacharia & Kakati, 2004).
The arrow crab, Stenorhynchus seticornis (Herbst, 1788) is
a common species in eastern Venezuelan coastal waters.
It lives in a variety of bottoms—rocks, corals, pebbles, sand,
or sand mixed with broken shell, wharf piling and rock
jetties—from the intertidal zone to 188 m in depth
(Williams, 1984) and ranges alo ng the west Atlanctic coasts,
from North Carolina to Argentina (Melo, 1996). It is com-
monly associated with sponges, stony corals, soft corals, gor-
gonians, anemones and echinoderms (Hayes et al., 1998).
The species is appreciated by aquarists owing to its extremely
long legs which resemble those of a spider. As stressed by
Rhyne et al. (2005) for the majoid crabs, the abbreviated
larval development of the species (two zoeae and one mega-
lopa) should be appealing for commercial culture if high
larval survival can be obtained.
Few studies have been conducted on the biology of S. seti-
cornis. Larval development was described by Yang (1976).
Quintero (1986) tested animal and vegetal based diets on
larval development; Herna
´
ndez et al. (1999) tested the
effects of starvation on the larvae; Cobo (2002) and
Okamori & Cobo (2003) studied some reproductive traits.
The purpose of the present work was to determine the
effects of various temperaturesalinity combinations on the
survival and duration of the larval stages of S. seticornis
under laboratory conditions.
MATERIALS AND METHODS
Ovigerous females of S. seticornis were collected from El
Morro beach, south-east coast of Margarita Is land,
Venezuela (10857
15
′′
N63848
30
′′
W), and brought to the lab-
oratory in aerated containers with seawater from the site of
collection. The animals were maintained in individual
aquaria at temperatures of 25278C and salinities of 36
38‰, and fed with Artemia, Mysidacea, and/or filamentous
green algae.
Five females with eggs near hatching (following the general
criteria given by Boschi, 1981) were selected, and isolated.
After hatching of their eggs, the females were removed from
the aquaria, and the larvae were subdivided into groups of
10 and transferred into glass bowl s containing 125 ml filtered
(5 m m) and UV-irradiated (1.5 l. min
21
) seawater at the
experimental temperatures and salinities. Only vigorously
swimming, apparently healthy larvae were used.
Selected larvae were reared in each of nine temperature (22,
25 and 288C) and salinity (30, 35 and 40‰) combinations.
The ranges of temperature and salinity used were chosen so
as to span the ranges found in coastal waters near Margarita
Island where the ovigerous females were collected. Each
rearing was carried out in six replicates (bowls with 10
larvae) per female. A total of 2700 larvae (540 per female)
were used in the experiment. Bowls were covered to reduce
evaporation, and/or contamination. All larvae were exposed
to a photoperiod of approximately 10 hours light and 14
hours dark. As a precaution against possible thermal shock,
larvae were acclimated to the experimental temperatures by
gradually reducing or increasing temperatures (approximately
1 degree/hour) within the bowls until the experimental con-
ditions were reached. Experimental temperatures were
obtained by placing the experimental bowls in temperature-
controlled water baths.
Forty ppt salinity was obtained by mixing locally-obtained
seawater with hypersaline water (147‰) from Boca Chica
Lagoon, Margarita Island. Both waters were previously fil-
tered, and UV-irradiated. Low salinities were obtained by
diluting filtered and UV-irradiated seawater with distilled
water.
Larvae were fed daily on newly hatched Artemia nauplii
(Great Salt Lake, Utah), (approximately 5 nauplii per ml), as
recommended by Quintero (1986). In order to avoid salinity
changes in the experimental bowls, nauplii were previously
screened and rinsed with filtered seawater at the experimental
salinities. Artemia cysts were decapsulated in a hypochlorite
solution (Ortiz et al., 1991).
The number of moults and mortality within each bowl was
recorded daily. Remaining larvae were transferred to clean
bowls with filtered and UV-treated seawater at the same temp-
erature and salinity, and newly hatched Artemia nauplii were
added. The experiment was concluded when all larvae had
moulted to the first crag stage or died.
Differences between survival (arcsin-transformed percen-
tages) and duration for each stage and for the complete devel-
opment were assessed by means of a factorial, model I,
analysis of variance (ANOVA) (Sokal & Ro
¨
hlf, 1981).
Females were treated as blocks. In the case of duration of
the first zoeae, bowls were considered as a possible source of
variation and treated as a nested factor. The Student
NewmanKeuls (SNK) multiple range test was used to con-
trast means when treatment differences were significant
(Sokal & Ro
¨
hlf, 1981). Perc entage survival for each stage
was calculated with respect to the number of larvae reaching
that stage.
RESULTS
As in other majoids, the early postembryonic development of
S. seticornis consists of two zoeal stages before attaining the
506 jesu
se.herna
ndez et al.
megalopa. The experimental conditions used in the present
work did not affect this pattern of development.
Survival
Day to day survival from hatching to the first crab stage at
different experimental temperaturesalinity combinations is
illustrated in Figure 1. The rate of survival shows a steeper
decline at 288C at all salinities.
Complete larval development occurred in all experimental
conditions, except at 288 C, 35‰, even though only 1% of
the larvae in the experiment reached the first crab stage. The
highest mean survival from hatching to the first crab stage
(4.5%) occurred at 258C; 30‰. At this temperature salinity
combination some recipients showed survivals as high as
26.6%, At 228C larvae required longer times (2735 days)
to complete development to the first crab (Figure 1).
first zoea
Mean survival at this stage was 61% under all experimental
conditions, and was influenced by salinity (F ¼ 3.43; P ,
0.05), but not by temperature (F ¼ 2.02; P . 0.05). The
effect of temperaturesalinity interaction was not significant
(F ¼ 0.32; P . 0.05) so the effects were considered as inde-
pendent. Only 30 and 35‰ differed in percentage survival.
Highest mean survival (61.3%) occurred at 288C, 30‰, the
lowest survival (49.3%), was at 258C, 35‰ (Figure 2).
second zoea
Mean survival at this stage varied from 26% at 288C, 35‰ to
59.6% at 258C, 30‰. Analysis of variance showed differences
due to different salinities (F ¼ 3.65; P , 0.05), and tempera-
tures (F ¼ 20.55, P , 0.001). The effect of temperaturesal-
inity interaction was not significant (F ¼ 0.59, P . 0.05).
The SNK test indicated that there was no difference in percen-
tage survival between 22 and 258C, which had the highest
survival. The observed differences are due to the considerable
reduction in survival at the highest temperature (288C), at all
salinities (Figure 2). Only extreme salinities differed in percen-
tage survival. The higher mean survi val was observed at 30‰
(Figure 2) .
megalopa
This stage showed the highest mortality during the exper-
iment. Percentage survi val was lower than 12% under all
experimental conditions. No megalopa moulted to the first
crab under 288C, 35‰, and only 1% larvae moulted at
288C, 40‰. The highest mean survival rate (12.2%) occurred
at 258C, 30‰ (Figure 2).
Percentage survival in megalopae differed significantly
within temperatures (F ¼ 4.41; P , 0.05) but not within
salinities (F ¼ 1.55; P . 0.05). Interaction between these two
parameters was not significant (F ¼ 1.93; P . 0.05).
Extreme temperatures (22 and 288C) resulted in decreased
percentage survival.
cumulative survival fr om hatching
to the first crab stage
Survival was low under all experimental conditions. The
highest mean survival (3.0%) occurred at 258C, 30‰ and
the lowest (0%) at 288C , 35‰.
Analysis of variance showed significant differences due to
temperatures only (F ¼ 4.19; P , 0.05). A SNK test indicated
differences between 25 and 28 8C, which showed the
maximum and minimum survival, respectively.
Rate of development
As shown in Figure 3, the duration of the two zoeal stages, the
megalopa and total time required for development to the first
crab stage were influenced to some extent by different sali-
nities and temperatures, with the effect of temperature being
greater. Times of development showed a gradual reduction
from low to high temperature.
Fig. 1. Percentage of survival from hatching to the first crab stage in
Stenorhynchus seticornis larvae reared in different salinities at 22, 25, and 288C.
temperature--salinity effects on s. seticornis larvae 507
first zoea
The time required by first zoeae to moult to the second stage
varied between 3 and 5 days (Figure 4A). At 25 and 28 8C the
first moult began at day 3, while at 228C it began at day 4. At
higher temperatures, all larvae completed ecdysis in a three
day period while at 228C it extended to five days. Regardless
of salinity, at 25 and 288C more than 60% of the larvae com-
pleted ecdysis during day 4 while at 228C the percentage of
moulting larvae on this day was reduced to ,2%.
Two-way ANOVA showed that temperatu re (F ¼ 1437.30;
P , 0.001) had a considerably greater influence than salinity
(F ¼ 12.22; P , 0.001). The temperaturesalinity interaction
was not significant (F ¼ 2.11; P . 0.05) indicating that the
effects of both variables were independent. The rate of devel-
opment increased with increasing temperature. Mean dur-
ation of first zoeae was 5.5 days (range 48 days) at 228C;
4.3 days (range 3 6 days) at 258C and 4.1 days (range 35
days) at 288C. In relation to salinity, duration was significantly
higher at 40‰, while no difference between 30 and 35‰
could be detected.
second zoea
Duration of this stage varied between 3 and 6 days (Figure 4B).
As in the former stage, the time required by the larvae to
moult to the megalopa stage declined with increasing temp-
eratures. Except for those larvae reared at 258C, 40‰, which
started to moult at day 8, at 25, and 288C, larvae started to
moult at day 7. At 228C ecdysis began at day 10 whereas the
majority of the larvae at 25, and 28 8C had completed ecdysis.
Analysis of variance showed differences in mean time
required to moult between temperatures (F ¼ 255.07; P ,
0.001) but not between salinities (F ¼ 2.88; P . 0.05).
Temperaturesalinity interaction was not significant (F ¼
0.25; P . 0.05). The SNK test indicated a significant decrease
in time for moulting with increasing temperature. On the
average, larvae required 6.5 days at 228C, 4.7 days at 258C
and 4.3 days at 288C.
megalopa
The persistent lag and the tendency for each moult to require a
greater period of time at the lower temperature continued in
Fig. 2. Mean (+SE) percentage survival of zoea and megalopa stages of Stenorhynchus seticornis reared at different salinities and temperatures. zoea I;
zoea II; megalopa.
Fig. 3. Comparison of time required for the development from hatching of
larvae of Stenorhynchus seticornis reared at different salinities and
temperatures. Vertical lines represent total range, blocks represent standard
deviation and horizontal lines are mean values.
508 jesu
se.herna
ndez et al.
the megalopae. In all test salinities, larvae reared at 288C
moulted to the first crab stage before those maintained at
228C began to moult. At 288C megalopae moulted to the
first crab between days 18 and 22 (5 days), but at 228C they
did not begin to moult until day 24, and needed 8 days for
all to complete ecdysis. At 258C, ecdysis began at day 17
and some larvae did not mo ult until day 27 (Figure 4C).
The ANOVA showed a significant effect of temperature
(F ¼ 3.55; P , 0.05), while no effect of salinity (F ¼ 0.06;
P . 0.05) was evident. Multiple comparison of means
showed a reduction in the duration of the megalopa stage at
25 and 288C, requiring on the average, 15.0 days at 228C,
12.2 days at 258C and 11.9 days at 288C.
cumulative rate of development from
hatching to the first crab stage
Depending on the experimental conditions, S. seticornis
required 17 to 31 days to complete development to the first
crab. The shortest time required to complete development
to the crab stage was, on average, 19.7 days (range 18 to 22
days) at 288C, 21.0 days (range 17 to 27 days) at 258C,
Fig. 4. Comparison of time of moult for (A) first zoeae; (B) second zoeae; (C) megalopae of Stenorhynchus seticornis reared at different salinities and temperatures.
228C; 258C; 288C.
temperature--salinity effects on s. seticornis larvae 509
while at 228C, the same stage was attained at an average time
of 26.9 days (range 24 to 31 days).
The ANOVA indicated a significant effect of temperature
only (F ¼ 14.07; P , 0.001). Larvae reared at 228C showed
an increased duration of larval development while no differ-
ence between 25 and 28 8C could be detected.
DISCUSSION
It is generally recognized tha t temperature, acting either inde-
pendently or simultaneously with other environmental
factors, is one of the major physical factors affecting survival,
duration of stages and growth of decapod larvae (Ong &
Costlow, 197 0; Nagaraj, 1993; La
´
rez et al., 2000; Zacharia &
Kakati, 2004). We found evidence that survival and duration
of the individual stages and the complete development to
the first crab of Stenorhynchus seticornis were affected by
the temperatures and salinities used; temperature having a
more pronounced effect than salinity.
Survival
The highest survival rates obtained for the first and second
zoeae (61.3% and 59.6%, respectively) were high compared
with those obtained by Quintero (1986) (34%, and 50%,
respectively) for the same species at 22248C; 36 38‰,
and similar feeding conditions. This author found a high mor-
tality during the first zoeal stag e and stated that during devel-
opment some stages require better care and/or better quality
or a special kind of food. However, those survival rates were
lower tha n that observed by Yang (1976) at 17298C; 32
36‰ (ZI: 77.8%, ZII: 64.3%). The differences obtained in
both cases may be due to the different temperaturesalinity
regimes and/or explained according to Costlow (1967),
Quintero (1986) and La
´
rez et al. (2000) who stated that survi-
val is extremely variable in eggs masses obtained from differ-
ent female crabs (genetic quality), differences in the natural
environment from which the ovigerous females were collected
and/or in eggs hatched at different times of the year.
High survival obtained in the zoeal stages could have been
favoured, to some extent by: (i) food supply. It is known that
the lack of food of proper size and nutritional value during the
period when larvae first begin feeding cause extensive mortal-
ities in some species (Sastry, 1983). Larvae of S. seticornis were
fed immediately after eclosion as recommended by Herna
´
ndez
et al. (1999) who tested the effects of starvation on S. seticornis
larvae, and found that only larvae fed immediately after eclo-
sion were able to moult to the second zoeal stage; (ii) water
quality. All water used in the experiment was previously fil-
tered and UV-irradiated in order to reduce harmful microor-
ganisms such as bacteria and protozoa; (iii) nutritional quality
of food and/or the fact that the Artemia cysts were decapsu-
lated using a hypochlorite solution, thus preventing the con-
tamination of the culture media with micro-organisms
(New & Singholka, 1984); and (iv) the larvae were transferred
daily to clean bowls, containing seawater at the same exper-
imental conditions avoiding thermal or sali nity shock.
In the present study, a reduction in the effect of salinity,
both in survival and duration of development with each suc-
cessive stage of development was observed; this suggests, as
stressed by Nagaraj (1993), that salinity tolerance increases
with each successive stage and euryhalinity may be attained
in the juvenile phase of the life history. Additionally,
Charmantier (1998) stated that the osmoregulatory capability
develops throughout the larval sequence of stages and com-
monly the tolerance ranges of larval stages to temperature
and salinit y are narrower than those of adults.
The highest survival rate in the megalopa stage, although
low, was higher than that obtained by Yang (1976) and
Quintero (1986) (7.4% and 6%, respectively). Yang (1976)
stated that the major cause of mortality in the megalopa
stage of S. seticornis in his experiment seemed to have been
a failure to complete moult into the crab stage because of an
inability of the animals to ext ract the lengthy pereopods.
Poor megalopal survival has been observed in other
majoids (Quintero, 1986; Harms & Seeger, 1989; La
´
rez et al.,
2000; Rhyne et al., 2005), as well as in other Decapoda
(Costlow et al., 1960; Mene et al., 1991; Luppi et al., 2003),
and has been attributed, in part, to a shift in the food prefer-
ences and/or in nutritional requirements, to the necessity of
an adequate substrate for settlement, and cannibalism.
According to Williams (1984), adults of S. seticornis are
omnivorous, while its zoeal stages are carnivorous. Maybe
megalopae of S. seticornis shift from the carnivorous diet
typical of the zoeae to an omnivorous diet typical of the
adults and, therefore, would require a mixed (animal and veg-
etable) food supply not necessarily of planktonic origin or
maybe they have higher energy requirements to fulfil meta-
bolic costs and/or growth, as well as preparation of the organ-
ism for metamorphosis as demonstrated in other decapods
(see Barros & Valenti, 2003 for reference s).
Although only 1% of the larvae in the experiment reached
the first crab stage, at 258C30‰ survival of megalopae was
as high as 12.2%. In nature, larval survival is generally very
low, often ,1% (Thorson, 1950; Morgan, 1995), and
decreases exponentially with time when mortality sources
such as predation or the likelihood of encount ering harsh
environmental conditions are relativel y constant over the
lifespan of a larva (Thorson, 1950; Morgan, 1995). The low
survival in the development to the first crab stage was due
to the high mortality in the megalopa stage, so the successful
completion of the life history of S. seticornis in the laboratory
appears to depend largely on the succes sful rearing of the
megalopa. The reasons for the high mortality of megalopae
of S. seticornis remain unsolved. This could be tested in
future studies focused on megalopae feeding and settlement
cues using the combination of temperature and salinity
(258C, 30‰) which yielded the higher survival rate (12.2%)
as reference.
On the other hand, the traditional water exchange of
rearing systems often requires larval manipulation and can
induce stress, so larvae could be raised to the megalopa and
then moved to an alternative rearing system that allow high
prey densities, good water quality, suspension of the larvae
in the water column (thus avoiding clumping), and where
settlement induction could be better achieved. This kind of
system was used succe ssfully by Rhyne et al. (2005) for
rearing Mithraculus forceps (A. Milne-Edwards, 1875) and
M. sculptus (Lamarck, 1818) larvae.
Rate of development
Although the rate of larval development may be genetically
determined (Sastry, 1983; Gonc¸alves et al., 1995), it may be
modified by environmental factors within the tolerance
510 jesu
se.herna
ndez et al.
limits for the species, and as well as by the quality and quantity
of available food (Sastry, 1983).
With the exception of the first zoeae, the duration of the
stages of development of S. seticornis was not affected by
the range of salinities used. The mean duration of the zoeal
stages, as well as the megalopa, was inversely related to temp-
erature. This last result is consistent with the general trend for
most other crustaceans including majoids (Wilson et al., 1979;
Scotto & Gore, 1980; Rengel et al., 1993; La
´
rez et al., 2000) and
other decapod larvae (Ong & Costlow, 1970; Goy et al., 1981;
Mene et al., 1991; Nagaraj, 1993; Paula et al., 2003; Zacharia &
Kakati, 2004), in which an inverse relationship between temp-
erature and duration of development has been also found.
Gonc¸alves et al. (1995) stated that, within certain limits,
higher temperatures shorten larval development, and that
this is important for the life history of the species since a shor-
tened developmental time increases the chance of reaching
maturity.
The effect of temperature on zoeal duration can have
important consequences to recruitment success. The length
of zoeal duration can affect dispersal, as well as total survival
to settlement based on the length of time zoeae are subjected
to predation. There could also be effects on survival and
growth based upon prey availability and energetics (Sulkin
& McKeen, 1994).
In crustaceans, moulting is a complex and continuous
process affected by metabolic activities controlled by
enzymes and moulting hormones (Passano, 1960; Chang,
1985; Skinner, 1985). As found for Mithrax caribbaeus
Rathbun, 1920 (La
´
rez et al., 2000), and Crangon uritari
Hayashi & Kim, 1999 (Li & Hong, 2007), the decrease in
the length of the intermoult period in S. seticornis at 288C
could be explained as the result of an increase in metabolic
rate along with an increase in the activity of enzymes and hor-
mones involved in the moulting process all as a consequence
of the increase in temperature within the tolerable physiologi-
cal limits for the species.
As observed by La
´
rez et al. (2000) for Mithrax caribbaeus,
the range of salinities used in the present work did not affect
significantly the time of development of the different stages of
S. seticornis. However, in other majoids a gradual increase in
larval life with decreasing salinity has been found (see La
´
rez
et al., 2000 for references). This may indicate that the effects
of salinity would be related to the physiological and adaptive
capacities and evolutionary history of each species.
Although laboratory experiments cannot exactly represent
natural conditions, they allow the analysis of the responses of
larvae to environmental variables in relation to adult habitats
and have greatly enhanced the understanding of the ecology
of pelagic crustacean larvae. They can also represent approxi-
mate environmental limits and how these variables affect
survival and rate of development of the larvae in nature
(Sastry, 1983).
Previous studies on the effects of temperature and salinity
on the larval development of Brachyura have fitted the
observed duration and mortality to a response surface, consid-
ering temperature, salinity and their interaction effects as pre-
dictor variables (Costlow et al., 1960; Costlow, 1967; Laughlin,
1983; Nagaraj, 1993; La
´
rez et al., 2000; Paula et al., 2003; Li &
Hong, 2007). We tried to fit a response surfa ce of these charac-
teristics to our data using a quadratic model. In all the cases,
the fitted model did not represent the data adequately.
Probably a greater number of temperaturesalinity
combinations, a higher order surface or the use of additional
variables must be included in the model.
As observed in the megalopa stage of other decapods
(Felder et al., 1985; Rodrı
´
guez et al., 1990; Stevens, 2003;
Suprayudi et al., 2004; Rhyne et al., 2005) moult frequency
and time of dev elopment of S. seticornis megalopae should
have been affected by factors other than salinity and tempera-
ture, such as nutrition, the absence of an appropriate substrate
and/or other settlement cues.
A longer period as megalopae increases the individual’s
probability to spread and reach an appropriate substrate
prior to metamorphosis (Jac kson & Strathmann, 1981).
Extension of the duration of late larval stages might allow
the species to colonize new areas or repopulate already colo-
nized ones, and enha nce the possibilities of gene flow
among local populations (Dı
´
az & Bevilacqua, 1986); neverthe-
less, a longer larval development period is correlated with a
rise in mortality, so its advantages are not obvious (Luppi
et al., 2003).
In order to make S. seticornis an ideal candidate for aqua-
culture, further studies are needed to address the nutritional
and substrate issues in order to improve the larval survivor-
ship and settlement of megalopae. Further research is also
needed to develop mass larvae rearing protocols as well as a
grow-out system for juveniles. This will allow the production
of quality animals at a low cost, enabling the commercial
production of the species.
ACKNOWLEDGEMENTS
We thank Dr Andrew Gannon and the anonymous referees
for assistance with revision of the manuscript, appreciative
comments and constructive criticism. This study received
financial support from the Consejo de Investigacio
´
ndela
Universidad de Oriente, Venezuela.
REFERENCES
Anger K. (1983) Temperature and the larval development of Hyas
araneus L. (Decapoda: Majidae); extrapolation of laboratory data to
field conditions. Journal of Experimental Marine Biology and Ecology
69, 203 215.
Barros H.P. and Valenti W.C. (2003) Ingestion rates of Artemia nauplii
for different larval stages of Macrobrachium rosenbergii. Aquaculture
217, 223 233.
Bolan
˜
os J.A. (1992) Desarrollo larval de Stenocionops furcata coelata
(Milne-Edwards, 1978) (Crustacea: Decapoda, Majidae), realizado en
condiciones experimentales. MSc thesis. Universidad de Oriente,
Cumana
´
, Venezuela.
Boschi E. (1981) Larvas de Crustacea Decapoda. In Boltovskoy D. (ed.)
Atlas del zooplancton del Atla
´
ntico Sudoccidental. Argentina:
Instituto Nacional de Investigacio
´
n y Desarrollo Pesquero (INIDEP),
pp. 699 758.
Boschi E. and Scelzo M.A. (1969) El desarrollo larval de los crusta
´
ceos
deca
´
podos. Ciencia e Investigacio
´
n 25, 146154.
Calado R., Narciso L., Morais S., Rhyne A.L. and Lin J. (2003) A rearing
system for the culture of ornamental decapod crustacean larvae.
Aquaculture 218, 329339.
Chang E.S. (1985) Hormonal control of molting in decapod crustacea.
American Zoologist 25, 179185.
temperature--salinity effects on s. seticornis larvae 511
Charmantier G. (1998) Ontogeny of osmoregulation in crustaceans: a
review. Invertebrate Reproduction and Development 33, 177 190.
Cobo V.J. (2002) Breeding period of the arrow crab Stenorhynchus seticor-
nis from Couves Island, south-eastern Brazilian coast. Journal of the
Marine Biological Association of the United Kingdom 82, 10311032.
Corbin J.S. (2001) Marine omamentals’99, conference highlights and pri-
ority recommendations. Aquarium Sciences and Conservation 3, 311.
Costlow J.D. (1967) The effect of salinity and temperature on survival and
metamorphosis of megalops of the blue crab, Callinectes sapidus.
Helgola
¨
nder Wissenschaftliche Meeresuntersuchungen 15, 8497.
Costlow J. and Bookhout C. (1968) The effect of environmental factors
on development of the land-crab Cardisoma guanhumi Latreille.
American Zoologist 8, 339410.
Costlow J., Bookhout C. and Monroe R. (1960) The effect of salinity and
temperature on larval development of Sesarma cinereum (Bosc) reared
in the laboratory. Biological Bulletin. Marine Biological Laboratory,
Woods Hole 118, 183202.
Crisp D.J. (1976) Settlement responses in marine organisms. In Newel
R.C. (ed.) Adaptation to environment: essays on the physiology of
marine animals. London: Butterworths, pp. 83124.
´
az H. and Bevilacqua M. (1986) Larval development of Aratus pisonii
(Milne-Edwards) (Brachyura, Grapsidae) from marine and estuarine
environments reared under different salinity conditions. Journal of
Coastal Research 2, 4350.
Ehlinger G.S. and Tankersley R.A. (2004) Survival and development of
horseshoe crab (Limulus polyphemus) embryos and larvae in hypersa-
line conditions. Biological Bulletin. Marine Biological Laboratory,
Woods Hole 206, 8794.
Felder D.L., Martin J.W. and Goy J.W. (1985) Patterns in early postlarval
development of decapods. In Wenner A.M. (ed.) Crustacean Issues 2.
Larval growth. Rotterdam and Boston: A.A. Balkema, pp. 163225.
Gonc¸alves F., Ribeiro R. and Soares A. (1995) Laboratory study of effects
of temperature and salinity on survival and larval development of a
population of Rhithropanopeus harrisii from the Mondego River
estuary, Portugal. Marine Biology 121, 639645.
Goy J., Bookhout C. and Costlow J. (1981) Larval development of the
spider crab Mithrax pleuracanthus Stimpson reared in the laboratory
(Decapoda: Brachyura: Majidae). Journal of Crustacean Biology 1,
5162.
Harms J. and Seeger B. (1989) Larval development and survival in seven
decapods species (Crustacea) in relation to laboratory diet. Journal of
Experimental Marine Biology and Ecology 133, 129 139.
Hayes F.E., Joseph V.L., Gurley H.S. and Wong B.Y.Y. (1998) Selection
by two decapod crabs (
Percnon gibbesi and Stenorhynchus seticornis)
associating with an urchin (Diadema antillarum) at Tobago, West
Indies. Bulletin of Marine Science 63, 241247.
Herna
´
ndez J.E., Bolan
˜
os J., Herna
´
ndez G. and Maga
´
nI.(1999) Estudios
preliminares del efecto de la inanicio
´
n en el desarrollo larval de
Stenorhynchus seticornis (Herbst, 1788) (Crustacea: Brachyura:
Majidae). Acta Cientı
´
fica Venezolana 50, 188.
Hicks G. (1973) Combined effects of temperature and salinity on
Hemigrapsus edwardsi (Hilgendorf) and H. creonulatus
(Milne-Edwards) from Wellington Harbour, New Zealand. Journal
of Experimental Marine Biology and Ecology 13, 1 4.
Jackson G.A. and Strathmann R.R. (1981) Larval mortality from offshore
mixing as a link between precompetent and competent periods of
development. The American Naturalist 118, 1626.
La
´
rez M.B., Palazo
´
n-Ferna
´
ndez J.L. and Bolan
˜
os J. (2000) The effect of
salinity and temperature on the larval development of Mithrax
caribbaeus Rathbun, 1920 (Brachyura: Majidae) reared in laboratory.
Journal of Plankton Research 22, 18551869.
Laughlin R. (1983) The effects of temperature and salinity on larval
growth of the horseshoe crab Limulus polyphemus. Biological
Bulletin. Marine Biological Laboratory, Woods Hole 164, 93103.
Li H.Y. and Hong S.Y. (2007) The effect of temperature and salinity on
survival and growth of Crangon uritai (Decapoda: Crangonidae)
larvae reared in the laboratory. Marine Ecology 28, 288295.
Lin J. and Shi H. (2002) Effect of broodstock diet on reproductive per-
formance of the golden banded coral shrimp Stenopus scutellatus.
Journal of the World Aquaculture Society 33, 383 386.
Luppi T.A., Spivak E.D. and Bas C.C. (2003) The effects of temperature
and salinity on larval development of Armases rubripes Rathbun, 1897
(Brachyura, Grapsoidea, Sesarmidae), and the southern limit of its
geographical distribution. Estuarine, Coastal and Shelf Science 58,
575585.
Melo G. (1996) Manual de identificac¸a
˜
o dos Brachyura (Caranguejos e
siris) do litoral brasileiro.Sa
˜
o Paulo: Editora Ple
ˆ
iade.
Mene L., Alvarez-Ossorio M.T., Gonza
´
lez-Gurriara
´
n E. and Valde
´
sE.
(1991) Effects of temperature and salinity on larval development of
Necora puber (Brachyura: Portunidae). Marine Biology 108, 7381.
Morgan S.G. (1995) Life and death in the plankton: larval mortality and
adaptation. In McEdward L. (ed.) Ecology of marine invertebrate
larvae. Boca Raton, FL: CRC Press, pp. 279 321.
Nagaraj M. (1992) Combined effects of temperature and salinity on the
development of the copepod Eurytemora affinis. Aquaculture 103,
6571.
Nagaraj M. (1993) Combined effects of temperature and salinity on the
zoeal development of the green crab Carcinus maenas (Linnaeus,
1758) (Decapoda: Portunidae). Scientia Marina 57, 1 8.
New M.B. and Singholka S. (1984) Cultivo del camaro
´
n de agua dulce.
Manual para el cultivo de Macrobrachium rosenbergii. FAO
Documento Te
´
cnico de Pesca 225, 1 118.
Okamori C.M. and Cobo V.J. (2003) Fecundity of the arrow crab
Stenorhynchus seticornis on the southern Brazilian coast. Journal of
the Marine Biological Association of the United Kingdom 83, 979 980.
Ong K. and Costlow J.D. (1970) The effect of salinity and temperature on
the larval development of the stone crab, Menippe mercenaria (Say),
reared in the laboratory. Chesapeake Science 11, 16 29.
Ortiz F., Sandoval M. and Araneda G. (1991) Metodologı
´
a y recomenda-
ciones te
´
cnicas para la cualificacio
´
n y utilizacio
´
n de las cepas nativas de
Artemia. Boletı
´
n de la Red de Acuicultura 5, 15 23.
Passano L.M. (1960) Molting and its control. In Waterman T.H. (ed.) The
physiology of Crustacea, Volume I. New York: Academic Press, pp.
473536.
Paula J., Nogueira Mendes R., Paci S., McLaughlin P., Gherardu F. and
Emmerson W. (2001) Combined effects of temperature and salinity
on the larval development of the estuarine mud prawn Upogebia
africana (Crustacea, Thalassinidea). Hydrobiologia 449, 141148.
Paula J., Nogueira Mendes R., Mwaluma J., Raedig C. and Emmerson
W. (2003) Combined effects of temperature and salinity on larval
development of the mangrove crab Parasesarma catenata Ortman,
1897 (Brachyura: Sesarmidae). Western Indian Ocean Journal of
Marine Science 2, 5763.
Quintero L.G. (1986) Efecto de varias dietas en la sobrevivencia y tiempo
de duracio
´
n de los estadios larvales de los cangrejos Mithrax caribbaeus
Rathbun, 1920 y Stenorhynchus seticornis Herbst, 1788 (Decapoda:
Brachyura) en condiciones de laboratorio. Undergraduate thesis.
Universidad de Oriente, Boca del
´
o, Venezuela.
512 jesu
se.herna
ndez et al.
Rengel I., Chung K., Bolan
˜
os J. and Fermı
´
nJ.(1993) El efecto de la
interaccio
´
n entre el cadmio, la salinidad y la temperatura sobre el
desarrollo larval de Mithrax verrucosus Milne-Edwards 1832
(Crustacea, Decapoda, Majidae). Ciencia 1, 1325.
Rhyne A.L., Penha-Lopes G. and Lin J. (2005) Growth, development, and
survival of larval Mithraculus sculptus (Lamark) and Mithraculus
forceps (A. Milne-Edwards) (Decapoda: Brachyura: Majidae): econ-
omically important marine ornamental crabs. Aquaculture 245,
183191.
Rodrı
´
guez B., Medina D. and Arrue M. (1990) Nutricio
´
n de larvas de
Mithrax spinosissimus en aguas del Pacı
´
fico. Boletı
´
n de la Red de
Acuicultura 4, 1517.
Sandifer P.A. (1973) Effects of temperature and salinity on larval devel-
opment of grass shrimp, Palaemonetes vulgaris (Decapoda, Caridea).
Fishery Bulletin 71, 115123.
Sastry A. (1970) Culture of brachyuran crab larvae using re-circulating
seawater system in the laboratory. Helgola
¨
nder Wissenschaftliche
Meeresuntersuchungen 20, 406416.
Sastry A. (1983) Pelagic larval ecology and development. In Vernberg F.J.
and Vernberg W.B. (eds) The biology of Crustacea, Volume 7. Behavior
and ecology. New York: Academic Press, pp. 214 269.
Scotto L. and Gore R. (1980) Larval development under laboratory
conditions of the tropical spider crab Mithrax (Mithraculus) coryphe
(Herbst, 1801) (Brachyura: Majidae). Proceedings of the Biological
Society of Washington 93, 551562.
Skinner D.M. (1985) Molting and regeneration. In Bliss D. and Mantel
L.H. (eds) The biology of Crustacea, Volume 9. New York: Academic
Press, pp. 43 146.
Sokal R.R. and Ro
¨
hlf F.J. (1981) Biometry. San Francisco: W.H. Freeman.
Stevens B.G. (2003) Settlement, substratum preference, and survival of
red king crab Paralithodes camtschaticus (Tilesius, 1815) glaucothoe
on natural substrata in the laboratory. Journal of Experimental
Marine Biology and Ecology 283, 6378.
Sulkin S. and McKeen G. (1994) Influence of temperature on larval devel-
opment of four co-occurring species of the brachyuran genus Cancer.
Marine Biology 118, 593600.
Suprayudi M.A., Takeuchi T. and Hamasaki K. (2004) Essential fatty
acids for larval mud crab Scylla serrata: implications of lack of the
ability to convert C18 unsaturated fatty acids to highly unsaturated
fatty acids. Aquaculture 231, 403 416.
Thorson G. (1950) Reproductive and larval ecology of marine bottom
invertebrates. Biological Reviews 25, 1 45.
Williams A. (1984) Shrimps, lobsters and crabs of the Atlantic coast of the
eastern United States, Maine to Florida. Washington, DC: Smithsonian
Institution Press.
Wilson K., Scotto L. and Gore R. (1979) Studies on decapod Crustacea
from the Indian River region Florida. XIII. Larval development
under laboratory conditions of the spider crab, Mithrax forceps (A.
Milne-Edwards, 1875) (Brachyura: Majidae). Proceedings of the
Biological Society of Washington 90, 735752.
Yang W. (1976) Studies on the western Atlantic arrow crab genus
Stenorhynchus (Decapoda: Brachyura: Majidae). I. Larval characters
of two species and comparison with other larvae of Inachinae.
Crustaceana 31, 157177.
and
Zacharia S. and Kakati V.S. (2004) Optimal salinity and temperature
for early developmental stages of Penaeus merguiensis De Man.
Aquaculture 232, 373382.
Correspondence should be addressed to:
J.L. Palazo
´
n-Ferna
´
ndez
Universidad de Oriente
Instituto de Investigaciones Cientı
´
ficas
Boca del
´
o, Isla de Margarita
Venezuela
emails: juis.palazon@icman.csic.es; jose.palazon@ne.udo.edu.ve
temperature--salinity effects on s. seticornis larvae 513
... Differences in tolerance to these factors partly depend on the stage of development, the species, and the habitat in which the species is found (Díaz and Bevilacqua, 1986). For S. seticornis, different survival rates were recorded in different locations, even with larvae exposed to different combinations of temperature and salinity (Yang 1976;Quintero 1986;Hernández and Bolãnos 2012), pointing to the need to set temperature and salinity according to the natural environment from where the ovigerous females were obtained. ...
... Factor two was salinity and the factor levels were: 25, 30, 35, and 40 PSU. These values represent the temperature and salinity variation range verified in previous studies carried out in the same locality (Alves et al. 2012) and these ranges are also the standards to cultivate small tropical decapods and compatible with stenotopic reef systems (Santana et al. 2003;Calado et al. 2003aCalado et al. , 2007Calado et al. , 2008Rhyne et al. 2005;Hernández et al. 2012;Monteforte-Sánchez et al. 2018). Only larvae hatched in 5 days after the sampling of the breeding females were used in the experiments (Gebauer et al. 2010) in order to prevent the rearing effect of the laboratory on larval quality. ...
... The best combination of temperature and salinity in the culture of S. seticornis larvae was 23 °C x 35 PSU, in which 6.6% of the larvae reached the first juvenile stage. The survival rate was higher than the maximum of 1% obtained by Hernández et al. (2012). Some previous studies (Thorson 1950;Morgan 1995;Hernández et al. 2012) suggest that the larval survival rate does not reach 2% in noncontrolled conditions, probably, due to a change in the alimentary preference and nutritional exigencies, despite an adequate substratum for megalopae settlement. ...
Article
Full-text available
Was tested the viability of a rearing system for management of broodstock of crabs and the salinity and temperature effect in larval survival and duration of the larval stages of Stenorhynchus seticornis. We used a completely randomized 4 × 4 factorial experiment with 16 treatments and 3 replicates per treatment. Factor one was temperature with the following factor levels: 23 °C, 25 °C, 27 °C, and 29 °C and factor two was salinity: 25, 30, 35, and 40 PSU. A total of 960 larvae (zoea I), obtained from 7 females kept in the rearing system, were transferred and distributed in batches of 20 larvae kept in glass flasks (500 mL) and then subjected to temperature and salinity experiments. They were checked daily for seedlings or deaths. The larval development took from 22 to 25 days (7.3 ± 4.14), and occurred only in experimental conditions of 23 °C x 35 PSU, in which 6.6% of larvae reached the juvenile stage. About the the viability of a rearing system, 15 ovigerous females were maintained in the rearing system, composed by 6 aquaria with water-recirculation and filtering system (400 L), released from 1 to 4 viable larval lots each during 2 months. Such results highlight the importance of studies in larval interaction with environmental conditions regarding larval survival, enabling the juvenile offer for commercial purposes and restocking of native populations, also promoting a efficient system for broodstock maintenance and larval attainment for aquaculture.
... The ability of larvae to cope with salinities outside the optimum range is normally also strongly influenced by the surrounding temperature (Crisp 1976;Anger 1991). In nature, environmental stressors such as warming and desalination usually do not occur in isolation and can therefore interactively affect the organism (Hernández et al. 2012). Therefore, studying the combined effects of these two factors is important to assess the response of a population to abiotic changes (Epifanio et al. 1998;Hernández et al. 2012). ...
... In nature, environmental stressors such as warming and desalination usually do not occur in isolation and can therefore interactively affect the organism (Hernández et al. 2012). Therefore, studying the combined effects of these two factors is important to assess the response of a population to abiotic changes (Epifanio et al. 1998;Hernández et al. 2012). ...
... Experimental temperatures were achieved in two sibling constant-temperature chambers at GEOMAR Helmholtz Centre for Ocean Research Kiel, adjusted to the respective air and water temperatures. As a precaution against possible thermal shock, larvae were acclimated after hatching to the higher temperature treatment (i.e., 23 °C) by gradually increasing the temperature at a rate of 1 °C per h (Hernández et al. 2012). ...
Article
Full-text available
Salinity is a common stressor restricting the distribution of various decapod crustaceans. The interactive effects of such regional stressors with global climate change drivers are important to be considered when aiming to realistically predict the potential of a species’ dispersal and further spread into new habitats. Within species, their larval stages commonly determine a species tolerance and with this their potential to invade and successfully develop a sustaining population. This laboratory study investigated the combined effect of salinity (6 levels, 10–25) and temperature (19 and 23 °C) on larval survival, development to megalopa, and feeding (in Zoea I, III, and V) of the decapod Hemigrapsus takanoi. Larval development and survival to megalopa were generally favored by increasing salinity. While no larva developed to the megalopa stage at 23 °C and a salinity of 16, in 19 °C some larvae could successfully develop under a salinity as low as 16. All larval stages fed generally more with increasing salinity and temperature, but there was no interaction between the two factors. The results revealed that the H. takanoi population from Kiel Fjord (southwestern Baltic Sea) is capable of completing its larval development under the current Kiel Fjord environmental conditions. The geographical spread of this H. takanoi population into the wider Baltic Proper may, however, be restricted mainly due to the inability to establish and maintain a self-sustaining population under lower salinity conditions. Furthermore, the projected desalination of the Baltic Sea together with rising temperatures due to global warming and heat waves in summer may likely exert additional stress to this existing population, unless H. takanoi adapts at appropriate rates.
... For example, strong physiological stress on intertidal organisms is expected at low tide under the influence of the Mediterranean climate as they are exposed to temperatures near or at the limit of their thermal tolerance (Helmuth et al., 2006;Somero, 2002). These effects can be exacerbated during the critical life phases of organisms such as the early stages which are highly sensitive to environmental change (Hernández et al., 2012;Torres et al., 2011). In fact, thermal stress is most harmful during larval and brood development times affecting survival and this has been documented previously in various decapod species (Hamasaki et al., 2009;Larez et al., 2000;Nurdiani and Zeng, 2007;Perez-Miguel et al., 2019). ...
... possible since they did not report survival rates, average larval survival of X. poressa increased with increasing temperature in the range of 17-25 • C. Similarly, the highest survival rates of the zoeal phase for other species of crabs were also reported at 25 • C and between 22 and 28 • C (Hernández et al., 2012;Larez et al., 2000). It is worth mentioning that the high survival rates reported in this study for X. poressa may be the result of the constant temperatures established for the experiments and enhanced by the continuous food supply and water quality. ...
... Therefore, at higher temperatures, the frequency of moulting increases and the duration of development decreases (Anger, 2001). A reduction in the development times at higher temperatures may be the result of an increase in metabolism and moultingenzymes and hormone activity rates (Anger, 1991;Hernández et al., 2012;Larez et al., 2000). In contrast, longer development periods due to lower temperatures enable larvae to spend more time in the water column and therefore enhances larval dispersal (Roberts et al., 2012). ...
Article
Temperature is a well-known environmental factor that affects the survival rate and development times of larvae in many brachyuran species. Intertidal species, such as the stone crab Xantho poressa are subject to aquatic and aerial temperature conditions, which make them suitable model species to analyse the effects of climate change. In this study, we analyse the effects of temperature on the duration of embryonic and larval development, as well as larval survival, of X. poressa under laboratory conditions. For brood incubation times, 18 ovigerous females were maintained at three different constant temperatures (17, 21 and 25 °C) in seawater (salinity of 35) until hatching. The larvae from other three ovigerous females were reared individually at the same temperature and in the same salinity conditions as for the brood incubation experiments. Embryonic incubation times decreased as temperature increased. Mean incubation times ranged between 23 and 9 days at 17 and 25 °C, respectively. Larvae development was completed at the three temperatures tested with the highest survival rate occurring at 25 °C. The duration of larval development also decreased with increasing temperature. The mean number of days from hatching to the megalopa stage ranged between 35 (17 °C) and 15 days (25 °C). An additional zoeal stage (ZV) was observed at the lowest temperature tested (17 °C).
... Ranges of 24-28°C and 34-37‰ are generally recommended, thus the values obtained on MLT 50 and MLS 50 suggest that S. debilis is compatible with stenotopic reef systems. These ranges are also the standards to cultivate small tropical decapods (Calado et al. 2003a(Calado et al. , 2007a(Calado et al. , 2008Goy et al. 1981;Hernández et al. 2012;Rhyne et al. 2005;Sandifer and Van Engel 1972;Santana et al. 2003) but fine points are yet to calibrate to achieve full-cycle production of S. debilis. ...
... This last piece of identity may be useful to assess further factors that are determinant in building protocols of full-cycle cultivation dedicated to S. debilis on the basis of what is known for commercial decapods and ornamental marine crabs (e.g. Calado et al. 2003aCalado et al. , 2007aCalado et al. , 2008Goy et al. 1981;Hernández et al. 2012;Rhyne et al. 2005;Sandifer and Van Engel 1972;Santana et al. 2003). Unfortunately, this objective was not accomplished for the moment. ...
Article
Full-text available
Ornamental marine species from the tropical west American coast are poorly known although many of them are being commercialized since a while ago. For example, yellow-arrow spider crabs, Stenorhynchus debilis (Brachyura: Inachidea), are frequently found for sale in web-based stores and as tenants into domestic aquaria. Therefore, the interest in studying the species’ requirements for management in land-based conditions is pertinent. This paper examines S. debilis as experimental actor. Specimens were collected along May to August 2015 into cultivation artifacts designed for pearl oysters farming at La Paz bay, Gulf of California. Five experiments were prepared towards two main objectives viewing at the practical framework of ornamental marine species: (1) Find the species’ profile into selected tests. Data included: anesthetic therapies, acute responses to temperature and salinity, special effects (food and feeding, density, sex-ratio, size, shelters, and handling in general), and notes concerning ovigerous females, eggs and larvae, and (2) Evaluate outputs seeking explanations for growth, survival and performances as a function of tropical-temperate and small-crab criteria. Our results agreed with expected bio-benchmarks overall, so did as to consistency of highlights regarding compatibility in domestic aquaria, and species-dependent aspects. Nevertheless, growth happened in a diet experiment even if only one crab out of the 24 under test displayed an incomplete –deadly—molt. A triangular-like Size Index was assessed, finding that two of the three food types tested had promoted better performance. Finally, this paper may contribute with some updates for the still incomplete mosaic of knowledge about ornamental marine crabs.
... The reproductive strategy of Percnon gibbesi, with a planktonic larval stage carried by currents, allows it to disperse over long distances [26]. Its routine habitat in the intertidal zone is usually on boulders that cover gravel bottoms and sands rich in organic matter, although its presence also extends along rocky infralittoral bottoms up to 25 m deep. ...
Article
Full-text available
Percnon gibbesi is a native crab species characteristic of intertidal and subtidal zones of the Atlantic coast of the European Macaronesian archipelagos (Azores, Madeira, and Canary Islands), and probably also in the neighbouring rocky coasts of northwest Africa. P. gibbesi is considered an invasive alien species in almost all of the Mediterranean, with expanding populations from Spain to Turkey, including Libya; however, its biology and ecology are highly unknown, despite all its range of distribution. In the intertidal zones of Gran Canaria Island, this crab, in the intertidal zones of Gran Canaria Island, shows a carapace length range between 4.1 and 22.7 mm (4.1–22.7 in males and 5.7–22.3 in females), where females showed higher weights and lengths than males on average; however, males predominated in all samples, with a sex ratio of 1:0.57. The L∞ for this crab was estimated to be 27 ± 3 mm (23 ± 4 mm for females and 25 ± 4 mm for males). The growth coefficient (K) was 0.24 year−1, the total mortality (Z) was Z = 1.71 year−1, and the natural mortality (M) was 0.47 year−1. Although females grow faster than males, males are more abundant in the larger length classes. Although the presence of ovigerous females indicated that reproduction takes place twice a year, from March to April and from August to September, the number of cohorts detected by the modal progression analysis showed that reproduction takes place all year.
... Ruscoe et al. (2004) noted a wide range of salinity tolerance in intermolt duration of the 18.43 mg crablets of mud crab (S. serrata) and they advised that these resistant features were considered the species a potential nominee for cultivation. In contrast, an ornamental marine crab species, Stenorhynchus seticornis, was reared at 30, 35 and 40‰ salinity levels, but the authors declared the salinity affected the percentage survival of the zoeal stages (Hernández et al., 2012). In the present study, marbled crabs (P. ...
Article
Full-text available
This study was conducted to evaluate the parameters on growth performance, molting frequency and carapace coloration of marbled crab (Pachygrapsus marmoratus Fabricius, 1787). Crabs were collected from Urla, İzmir. The experiment was performed in 10 L plastic containers filled with 6 L of seawater at four different salinity levels (5‰, 15‰, 25‰ and 35‰). Ten crabs with an initial mean weight of 0.78±0.03 g were placed in each container with three replicates. Crabs were fed once a day with a commercial diet (46% protein and 18% lipid) for 12 weeks. At the end of the study, the final mean weight (FMW) of the 25‰ group was significantly higher than the 5‰ and 15‰ groups (P<0.05). Specific growth rates (SGR) of the 15‰ and the 35‰ groups and feed conversion ratio (FCR) of the 25‰ group were significantly higher than the 5‰ group (P<0.05). The mean molting frequency (MMF) of the 25‰ group was significantly higher than the 5‰ group (P<0.05). Final lightness (L*) of the 5‰ and 15‰ were significantly lower than their initials (P<0.05). Final redness (a*) of the 25‰ group was the highest among the experimental groups (P<0.05). Final yellowness (b*) of the 25‰ group was significantly higher than the 5‰ and 15‰ groups (P<0.05). According to the results, it is recommended to keep the salinity at 25‰ under marble crab rearing conditions. Further studies are needed to reveal the potential properties of this species in marine aquariums.
... Water temperature is a key factor affecting both the survival of brachyuran larvae (Hernández et al., 2012) and the duration of their development (Anger, 1991;Lárez et al., 2000). Survival is reduced at extreme temperatures, and temperature is an especially important factor in more temperate regions, where seasonal fluctuations in temperature are more extreme than those experienced in more stable tropical environments, leading to distinct patterns of development (Bryars & Havenhand, 2006). ...
Article
Full-text available
Brachyuran crabs, like other decapod crustaceans, adopt a number of different strategies for larval dispersal. We verified the influence of variations in temperature, salinity, and pH on the abundance and taxonomic composition of brachyuran larvae in an Amazonian estuary and found evidence of both retention and export dispersal strategies. We identified larvae of 20 different taxa belonging to the families Grapsidae, Ocypodidae, Panopeidae, Pinnotheridae, and Sesarmidae. Ucides cordatus (Linnaeus, 1763) (Ocypodidae), Pachygrapsus gracilis (Saussure, 1857) (Grapsidae), Leptuca cumulanta (Crane, 1943) (Ocypodidae), and Armases rubripes (Rathbun, 1897) (Sesarmidae) were the most abundant species. Most of the taxa present in the study area were at the zoea I stage but later larval stages were found in some species, indicating retention and export. Results were supported by canonical correspondence analysis and general linear model, which related larval community structure and reproduction patterns to variations in salinity, influenced primarily by the enormous discharge of the Amazon River and the high rainfall levels in the region. Further investigations of the distribution of larvae on the continental shelf are necessary to confirm the identified dispersal patterns. The study also presents novel data on the composition, abundance, and dispersal of brachyuran larvae in the tropical estuaries of the Amazon River.
... The marine ornamental species trade exploits S. seticornis because of their hardiness in captivity and unique colouration and morphology (Calado et al. 2003). Aside from their exploitation, only a few aspects are known about the larval development of S. seticornis, such as their complete description (Yang 1976) and how temperature and salinity affect said development (Hernández et al. 2012(Hernández et al. ). 2006). ...
Article
Full-text available
Knowledge of the critical points in larval stages is essential to evaluate the physiological state of the larvae in their natural environment. This study investigated the nutritional vulnerability index (NVI) of the first (ZI) and second (ZII) zoeal stages of Stenorhynchus seticornis. Zoeae were assigned to two experiments: (1) point of no return (PNR), consisting of treatments with increasing days of starvation and subsequent days of feeding; and (2) point of reserve saturation (PRS), consisting of treatments with increasing days of feeding and subsequent days of starvation. There were two control groups: continuous starvation (CS) and continuous feeding (CF). Mortality was used to estimate the time when 50% of initially starved larvae (PNR50) lost the ability to moult to the next stage and when 50% of initially fed larvae (PRS50) were capable of moulting to the next stage. The mean (±s.d.) development time of ZI and ZII under CF was 4.4 ± 1.2 and 5.1 ± 1.8 days respectively. Mortality in the CF groups was 30 and 52% for ZI and ZII respectively. For ZI, PNR50 and PRS50 were 1.0 ± 0.0 and 2.1 ± 1.0 days respectively. The estimated NVI for ZI was 2.2, which indicates that S. seticornis depends on exogenous food and is considered planktotrophic during the first larval stage.
Preprint
Full-text available
Invasive species are a growing threat to marine ecosystems, and the recent proliferation of the Atlantic blue crab (Callinectes sapidus) in the Po Delta (Italy) has had significant ecological and economic impacts, particularly on clam farming. This study explores the influence of C. sapidus on clam production in the Po Delta, combining biological and ecological data with socio-economic analysis. Field data collected between August and December 2023 from the Canarin and Scardovari Lagoons revealed seasonal fluctuations in crab abundance, with a peak in captures during the warmer months. The predatory behaviour of C. sapidus has led to a sharp decline in clam production, reaching near-zero levels in early 2024. Statistical analysis confirmed a strong correlation between the increase of the invasive crab population and the decrease in clam yields. This study also explores potential management strategies, including the economic valorisation of C. sapidus as a commercial resource, turning an ecological challenge into an opportunity. These findings highlight the urgent need for targeted management interventions to mitigate the impact of this invasive species on local fisheries and ecosystems.
Article
Temperature and light are important factors affecting production in the aquaculture industry, as they can drive behaviour and physiological responses of free‐swimming larval stages. However, the influence of light on crustacean farming has received little consideration. The common spider crab Maja brachydactyla Balss, 1922 has a great potential for aquaculture because of the easy maintenance, high fecundity, and short larval development. In order to optimize larval culture techniques, we quantified the influence of temperature and light on larval survival, development, and elemental (carbon and nitrogen) body composition. Constant darkness resulted in longer developmental time as compared with daily light photoperiod (6–16 light hours). Larvae reared under constant darkness showed also reduced dry mass, carbon and nitrogen content, and C:N ratio. We also found carry‐over effects of light conditions: constant darkness experienced during the zoeal stage led to increased developmental time in the megalopa stage. Temperature and light showed additive effects. We optimized the larval culture of M. brachydactyla requiring around 14 days from hatch to first juvenile by keeping cultures under 21 ± 1°C and light sources simulating the daily light cycle.
Article
Larvae of Mithrax caribbaeus were reared in the laboratory in a factorial experiment employing three temperatures (22, 25 and 28 °C) and three salinities (32, 35 and 38‰). Survival and duration of larval stages were recorded. Ovigerous females of M.caribbaeus were collected from the south-eastern coast of Margarita Island, Venezuela, and maintained in individual aquaria until hatching. Eggs from three of the females hatched in the laboratory. Larvae from each hatching were subdivided into groups of 10 and reared in plastic bowls containing 200 ml filtered and UV-irradiated sea water at different temperature-salinity combinations. Larvae were transferred daily to clean bowls with newly hatched Artemia nauplii, and the number of molts and mortality within each bowl was recorded. Complete larval development of M.caribbaeus occurred under all experimental conditions. Salinity had the greatest effect on percentage survival of each larval stage and complete development up to the first crab stage. The first zoeal stage exhibited the highest survival rate. Maximum survival for this stage occurred at 25 °C, 32-35‰. Survival in the second zoeal stage and the megalopa was affected only by salinity. Effects of temperature and salinity on survival decreased with advance in development. The duration of the two zoeal stages, the megalopa, and development to the first crab stage showed a gradual reduction with increasing temperature. Salinity showed an effect on the duration of zoeal stages but not on the megalopal stage. Development from hatching to the first crab stage required 8-18 days, depending on the temperature-salinity combination, and was inversely related to temperature, averaging 14.3 days at 22 °C, 11.8 days at 25 °C and 9.2 days at 28 °C.
Article
Larval development of the mangrove crab Aratus pisonii was studied using larvae hatched from females collected from 2 populations off the Venezuelan coast: one located at mangrove swamps associated with an estuarine coastal lagoon and the other at a marine bay. Laboratory rearings were performed using offshore sea water diluted to 15, 25 and 35per milleS. Salinity and larval origin have a significant effect only upon survival of zoea I. Only mean duration of zoea I of marine larvae were significantly affected by salinity. A differential response was found for the whole larval phase associated with salinity; this response was similar for marine and estuarine larvae. Differences in larval survival are interpreted as an adaptation of the species to the environmental conditions of localities where adults were collected.-from Authors
Article
The larvae of two populations, presumably both belonging to the western Atlantic majid crab, Stenorhynchus seticornis (Herbst) were reared in the laboratory, and described and illustrated. Larvae obtained from the shallow water population differ from the larvae obtained from the deep water population. The marked larval character differences suggest that there are two species involved in the present nominal species of