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Fulltext Population divergence in compensatory growth responses and their costs in sticklebacks

Ab Ghani NI, Merilä J

Ecol Evol, 2015 Jan;5(1):7-23.
PMID: 25628860 DOI: 10.1002/ece3.1342

Compensatory growth (CG) may be an adaptive mechanism that helps to restore an organisms' growth trajectory and adult size from deviations caused by early life resource limitation. Yet, few studies have investigated the genetic basis of CG potential and existence of genetically based population differentiation in CG potential. We studied population differentiation, genetic basis, and costs of CG potential in nine-spined sticklebacks (Pungitius pungitius) differing in their normal growth patterns. As selection favors large body size in pond and small body size in marine populations, we expected CG to occur in the pond but not in the marine population. By manipulating feeding conditions (viz. high, low and recovery feeding treatments), we found clear evidence for CG in the pond but not in the marine population, as well as evidence for catch-up growth (i.e., size compensation without growth acceleration) in both populations. In the marine population, overcompensation occurred individuals from the recovery treatment grew eventually larger than those from the high feeding treatment. In both populations, the recovery feeding treatment reduced maturation probability. The recovery feeding treatment also reduced survival probability in the marine but not in the pond population. Analysis of interpopulation hybrids further suggested that both genetic and maternal effects contributed to the population differences in CG. Hence, apart from demonstrating intrinsic costs for recovery growth, both genetic and maternal effects were identified to be important modulators of CG responses. The results provide an evidence for adaptive differentiation in recovery growth potential.

Matched MeSH terms: Body Size
Fulltext Fish oil supplementation is beneficial on caloric intake, appetite and mid upper arm muscle circumference in children with leukaemia

Abu Zaid Z, Shahar S, Jamal AR, Mohd Yusof NA

Asia Pac J Clin Nutr, 2012;21(4):502-10.
PMID: 23017308

A randomised trial was carried out to determine the effect of supplementation of fish oil among 51 children with leukaemia aged 4 to 12 years on appetite level, caloric intake, body weight and lean body mass. They were randomly allocated into the trial group (TG) and the control group (CG). At baseline, 30.8% of TG subjects and 44.0% of CG subjects were malnourished and 7.7% of subject from TG and 28.0% from CG were classified as stunted. The majority of subjects from TG and CG were in the mild malnutrition category for mid upper arm muscle circumference (MUAMC)-for-age. The TG group showed significant increment in MUAMC (0.13 cm vs -0.09 cm) compared with CG at 8 weeks (p<0.001). There was a significant higher increase for appetite level (0.12±0.33) (p<0.05) and an increasing trend on energy and protein intake in the TG group (213±554 kcal; 3.64 ±26.8 g) than in the CG group. In conclusion, supplementation of fish oil has a positive effect on appetite level, caloric intake and MUAMC among children with leukaemia.

Matched MeSH terms: Body Size
The mercury levels in crustaceans and cephalopods from Peninsular Malaysia

Ahmad NI, Noh MF, Mahiyuddin WR, Jaafar H, Ishak I, Azmi WN, et al.

Environ Sci Pollut Res Int, 2015 Sep;22(17):12960-74.
PMID: 25916470 DOI: 10.1007/s11356-015-4415-9

This study is to determine total mercury in edible tissues of eight species of cephalopods and 12 species of crustaceans purchased from 11 identified major fish landing ports and wet markets throughout Peninsular Malaysia. The concentration of mercury was measured by cold vapor atomic absorption spectrometry (AAS) technique using the Perkin Elmer Flow Injection Mercury System (FIMS-400). In general, the mercury levels were low with concentrations in cephalopods ranging from 0.099 to 2.715 mg/kg dry weight (or 0.0184-0.505 mg/kg wet weight) and in crustaceans ranging from 0.057 to 1.359 mg/kg dry weight (or 0.0111-0.265 mg/kg wet weight). The mercury levels showed no significant differences (P > 0.05) between species for both cephalopods and crustaceans. There was no significant correlation between mercury concentrations and the body size of individual for both groups as well. Comparisons with mercury levels obtained found from other previous studies and/or species noted that they were of the same magnitude or relatively low compared to various locations reported worldwide.

Matched MeSH terms: Body Size
Fulltext Mercury levels of marine fish commonly consumed in Peninsular Malaysia

Ahmad NI, Noh MF, Mahiyuddin WR, Jaafar H, Ishak I, Azmi WN, et al.

Environ Sci Pollut Res Int, 2015 Mar;22(5):3672-86.
PMID: 25256581 DOI: 10.1007/s11356-014-3538-8

This study was conducted to determine the concentration of total mercury in the edible portion of 46 species of marine fish (n = 297) collected from selected major fish landing ports and wholesale markets throughout Peninsular Malaysia. Samples were collected in June to December 2009. Prior to analysis, the fish samples were processed which consisted of drying at 65 °C until a constant weight was attained; then, it was grounded and digested by a microwave digestion system. The analytical determination was carried out by using a mercury analysis system. Total mercury concentration among fish species was examined. The results showed that mercury concentrations were found significantly higher (p 20 cm) and were positively related with fish size (length and weight) in all fish samples. Despite the results, the level of mercury in marine fish did not exceed the permitted levels of Malaysian and JECFA guideline values at 0.5 mg/kg methylmercury in fish.

Matched MeSH terms: Body Size
Fulltext Relationship of self-reported body size and shape with risk for prostate cancer: A UK case-control study

Aladwani M, Lophatananon A, Robinson F, Rahman A, Ollier W, Kote-Jarai Z, et al.

PLoS One, 2020;15(9):e0238928.
PMID: 32941451 DOI: 10.1371/journal.pone.0238928

INTRODUCTION: Previous evidence has suggested a relationship between male self-reported body size and the risk of developing prostate cancer. In this UK-wide case-control study, we have explored the possible association of prostate cancer risk with male self-reported body size. We also investigated body shape as a surrogate marker for fat deposition around the body. As obesity and excessive adiposity have been linked with increased risk for developing a number of different cancers, further investigation of self-reported body size and shape and their potential relationship with prostate cancer was considered to be appropriate.
OBJECTIVE: The study objective was to investigate whether underlying associations exist between prostate cancer risk and male self-reported body size and shape.
METHODS: Data were collected from a large case-control study of men (1928 cases and 2043 controls) using self-administered questionnaires. Data from self-reported pictograms of perceived body size relating to three decades of life (20's, 30's and 40's) were recorded and analysed, including the pattern of change. The associations of self-identified body shape with prostate cancer risk were also explored.
RESULTS: Self-reported body size for men in their 20's, 30's and 40's did not appear to be associated with prostate cancer risk. More than half of the subjects reported an increase in self-reported body size throughout these three decades of life. Furthermore, no association was observed between self-reported body size changes and prostate cancer risk. Using 'symmetrical' body shape as a reference group, subjects with an 'apple' shape showed a significant 27% reduction in risk (Odds ratio = 0.73, 95% C.I. 0.57-0.92).
CONCLUSIONS: Change in self-reported body size throughout early to mid-adulthood in males is not a significant risk factor for the development of prostate cancer. Body shape indicative of body fat distribution suggested that an 'apple' body shape was protective and inversely associated with prostate cancer risk when compared with 'symmetrical' shape. Further studies which investigate prostate cancer risk and possible relationships with genetic factors known to influence body shape may shed further light on any underlying associations.

Matched MeSH terms: Body Size*
Influence of habitat structure and environmental variables on larval fish assemblage in the Johor Strait, Malaysia

Ara R, Arshad A, Amin SMN, Idris MH, Gaffar MA, Romano N

J Environ Biol, 2016 07;37(4 Spec No):745-54.
PMID: 28779734

Our previous study demonstrated that among different habitat sites (mangrove, estuary, river, seagrass and Open Sea) in Johor Strait, Malaysia, seagrass showed highest family diversity and abundance of larval fish. However, it is unclear whether this was due to difference in habitat complexity or water quality parameters.? To test this, larval fish were collected by using a bongo net equipped with a flow meter by subsurface horizontal towing from different habitats in Johor Strait between October 2007 and September 2008.? Various physico-chemical parameters were measured and then examined for any relationship to fish larvae diversity and abundance. Among the 24 families identified from the sites, seven families (Blenniidae, Clupeidae, Mullidae, Nemipteridae, Syngnathidae, Terapontidae and Uranoscopeidae) were significantly correlated with the tested waters quality parameters.? Salinity showed a positive and negative significant correlation with Clupeidae (p < 0.01) and Uranoscopeidae (p < 0.05), respectively. Terapontidae was significantly correlated with dissolved oxygen (p < 0.01), while both Mullidae and Syngnathidae were significantly correlated with pH (p < 0.05). However, a canonical correspondence analysis test indicated weak overall correlation (36.4%) between larval assemblage and in the seagrass-mangrove ecosystem of Johor Strait, Malaysia. This likely indicates that habitat structure was more important in determining larval abundance (highest in the seagrass habitat) as compared to water quality at the tested sites. This study emphasizes the need to conserve seagrass beds as important nursery grounds for various fish larvae to ensure adequate recruitment and ultimately sustainable fisheries management. ?

Matched MeSH terms: Body Size
Notes on the occurrence of the tropical eel Anguilla bicolor bicolor in Peninsular Malaysia, Malaysia

Arai T, Chino N, Zulkifli SZ, Ismail A

J Fish Biol, 2012 Mar;80(3):692-7.
PMID: 22380562 DOI: 10.1111/j.1095-8649.2011.03154.x

Previous studies indicated that a tropical freshwater eel Anguilla bicolor bicolor occurs in Africa, India, Sri Lanka, Bangladesh, Myanmar, Indonesia and Australia, but an intensive survey has indicated an extended distribution range for the species into Peninsular Malaysia. Thus, A. b. bicolor is a native subspecies of Malaysia.

Matched MeSH terms: Body Size
Seven new species of the earthworm genus Metaphire Sims & Easton, 1972 from Thailand (Clitellata: Megascolecidae)

Bantaowong U, Chanabun R, James SW, Panha S

Zootaxa, 2016;4117(1):63-84.
PMID: 27395158 DOI: 10.11646/zootaxa.4117.1.3

Earthworm specimens collected from various parts of Thailand were found to contain seven new species of the genus Metaphire Sims & Easton, 1972. These are M. songkhlaensis sp. n. in the octothecal pulauensis species group, M. trangensis sp. n. in the octothecal ignobilis species group, M. khaoluangensis sp. n. and M. khaochamao sp. n. in the sexthecal houlleti species group, M. doiphamon sp. n. in the sexthecal peguana species group, M. saxicalcis sp. n. in the quadrithecal planata species group, and the bithecal M. surinensis sp. n. Type material of some established species from Thailand or northern Malaysia was reinvestigated and illustrated to confirm the status of the new species and to facilitate species comparisons: M. pulauensis (Beddard, 1900), M. baruana (Stephenson, 1932), both with newly designated lectotypes, and M. planata (Gates, 1936), illustrated and redescribed.

Matched MeSH terms: Body Size
Fulltext Evaluation of trace metal levels in tissues of two commercial fish species in Kapar and Mersing coastal waters, Peninsular Malaysia

Bashir FA, Shuhaimi-Othman M, Mazlan AG

J Environ Public Health, 2012;2012:352309.
PMID: 22046193 DOI: 10.1155/2012/352309

This study is focused on evaluating the trace metal levels in water and tissues of two commercial fish species Arius thalassinus and Pennahia anea that were collected from Kapar and Mersing coastal waters. The concentrations of Fe, Zn, Al, As, Cd and Pb in these coastal waters and muscle, liver and gills tissues of the fishes were quantified. The relationship among the metal concentrations and the height and weight of the two species were also examined. Generally, the iron has the highest concentrations in both water and the fish species. However, Cd in both coastal waters showed high levels exceeding the international standards. The metal level concentration in the sample fishes are in the descending order livers > gills > muscles. A positive association between the trace metal concentrations and weight and length of the sample fishes was investigated. Fortunately the level of these metal concentrations in fish has not exceeded the permitted level of Malaysian and international standards.

Matched MeSH terms: Body Size
Two new species of Pharta Thorell, 1891 with the description of Ibana senagang gen. et sp. nov. (Araneae: Thomisidae)

Benjamin SP

Zootaxa, 2014;3894:177-82.
PMID: 25544630 DOI: 10.11646/zootaxa.3894.1.15

Two new species of Pharta, P. sudmannorum sp. nov. (♂♀, Borneo) and P. koponeni sp. nov. (♂, Thailand) are described. Furthermore, Ibana senagang gen. nov. & sp. nov. from Malaysia is described based on its exceptional palp, which has a reduced, movable conductor and thick-long spines on the distal, ventral surface of the tibia, reminiscent of Epidius Thorell, 1877.

Matched MeSH terms: Body Size
A new species of Angaeus from Malaysia with possible affinity to related genera within Stephanopinae (Araneae: Thomisidae)

Benjamin SP

Zootaxa, 2017 Oct 17;4337(2):297-300.
PMID: 29242447 DOI: 10.11646/zootaxa.4337.2.10

The crab spider genus Angaeus Thorell, 1881 currently contains 10 described species (Benjamin 2013; WSC 2017). All species of the genus are restricted to tropical Asia. The aim of this correspondence is to illustrate and describe a new species of the genus characterized by a number of features previously found in the genera Angaeus, Borboropactus Simon, 1884, Epidius Thorell, 1877 and Geraesta Simon, 1889. The most unusual feature is the elongated tibia of the male palp that was previously thought to be diagnostic of Epidius (Figs 1, 2, 8; character 1 in Benjamin 2011; Benjamin 2017). However, the new species lacks tibial macrosetae (Figs 1, 2, 8) and lacks a flexibly attached MA, both also being characteristics of Epidius (characters 2 and 18 in Benjamin 2011). Furthermore, this new species differs considerably in general appearance from all known species of Epidius.

Matched MeSH terms: Body Size
Revision of the genus Coeligetes from Malaysia and Indonesia, and description of Coeligetoides gen. nov. (Coleoptera: Chrysomelidae: Galerucinae)

Bezděk J

Zootaxa, 2016 Mar 04;4085(4):504-24.
PMID: 27394316 DOI: 10.11646/zootaxa.4085.4.3

The species of the genus Coeligetes Jacoby, 1884 distributed in Malaysia and Indonesia are revised, illustrated and keyed. New species, C. howardi sp. nov. from Borneo is described. New synonymy Coeligetes submetallica Jacoby, 1884 = C. wilcoxi Mohamedsaid, 1994 (syn. nov.) is proposed. New genus and species Coeligetoides trifurcatus gen. nov., sp. nov. (Malaysia, Brunei, Indonesia and Thailand) is described, illustrated and compared with related genera.

Matched MeSH terms: Body Size
Fulltext Lowland biotic attrition revisited: body size and variation among climate change 'winners' and 'losers'

Brodie JF, Strimas-Mackey M, Mohd-Azlan J, Granados A, Bernard H, Giordano AJ, et al.

Proc Biol Sci, 2017 01 25;284(1847).
PMID: 28100818 DOI: 10.1098/rspb.2016.2335

The responses of lowland tropical communities to climate change will critically influence global biodiversity but remain poorly understood. If species in these systems are unable to tolerate warming, the communities-currently the most diverse on Earth-may become depauperate ('biotic attrition'). In response to temperature changes, animals can adjust their distribution in space or their activity in time, but these two components of the niche are seldom considered together. We assessed the spatio-temporal niches of rainforest mammal species in Borneo across gradients in elevation and temperature. Most species are not predicted to experience changes in spatio-temporal niche availability, even under pessimistic warming scenarios. Responses to temperature are not predictable by phylogeny but do appear to be trait-based, being much more variable in smaller-bodied taxa. General circulation models and weather station data suggest unprecedentedly high midday temperatures later in the century; predicted responses to this warming among small-bodied species range from 9% losses to 6% gains in spatio-temporal niche availability, while larger species have close to 0% predicted change. Body mass may therefore be a key ecological trait influencing the identity of climate change winners and losers. Mammal species composition will probably change in some areas as temperatures rise, but full-scale biotic attrition this century appears unlikely.

Matched MeSH terms: Body Size*
Revision and phylogenetic analysis of the orb-weaving spider genus Glenognatha Simon, 1887 (Araneae, Tetragnathidae)

Cabra-García J, Brescovit AD

Zootaxa, 2016 Jan 27;4069(1):1-183.
PMID: 27395905 DOI: 10.11646/zootaxa.4069.1.1

A taxonomic revision and phylogenetic analysis of the spider genus Glenognatha Simon, 1887 is presented. This analysis is based on a data set including 24 Glenognatha species plus eight outgroups representing three related tetragnathine genera and one metaine as the root. These taxa were scored for 78 morphological characters. Parsimony was used as the optimality criterion and a sensitivity analysis was performed using different character weighting concavities. Seven unambiguous synapomorphies support the monophyly of Glenognatha. Some internal clades within the genus are well-supported and its relationships are discussed. Glenognatha as recovered includes 27 species, four of them only known from males. A species identification key and distribution maps are provided for all. New morphological data are also presented for thirteen previously described species. Glenognatha has a broad distribution occupying the Neartic, Afrotropic, Indo-Malaya, Oceania and Paleartic regions, but is more diverse in the Neotropics. The following eleven new species are described: G. vivianae n. sp., G. caaguara n. sp., G. boraceia n. sp. and G. timbira n. sp. from southeast Brazil, G. caparu n. sp., G. januari n. sp. and G. camisea n. sp. from the Amazonian region, G. mendezi n. sp., G. florezi n. sp. and G. patriceae n. sp. from northern Andes and G. gouldi n. sp. from Southern United States and central Mexico. Females of G. minuta Banks, 1898, G. gaujoni Simon, 1895 and G. gloriae (Petrunkevitch, 1930) and males of G. globosa (Petrunkevitch, 1925) and G. hirsutissima (Berland, 1935) are described for the first time. Three new combinations are proposed in congruence with the phylogenetic results: G. argyrostilba (O. P.-Cambridge, 1876) n. comb., G. dentata (Zhu & Wen, 1978) n. comb. and G. tangi (Zhu, Song & Zhang, 2003) n. comb., all previously included in Dyschiriognatha Simon, 1893. The following taxa are newly synonymized: Dyschiriognatha montana Simon, 1897, Glenognatha mira Bryant, 1945 and Glenognatha maelfaiti Baert, 1987 with Glenognatha argyrostilba (Pickard-Cambridge, 1876) and Glenognatha centralis Chamberlin, 1925 with Glenognatha minuta Banks, 1898.

Matched MeSH terms: Body Size
Fulltext Safety of thoracic pedicle screw application using the funnel technique in Asians: a cadaveric evaluation

Chan CY, Kwan MK, Saw LB

Eur Spine J, 2010 Jan;19(1):78-84.
PMID: 19763636 DOI: 10.1007/s00586-009-1157-8

The objective of this cadaveric study is to determine the safety and outcome of thoracic pedicle screw placement in Asians using the funnel technique. Pedicle screws have superior biomechanical as well as clinical data when compared to other methods of instrumentation. However, misplacement in the thoracic spine can result in major neurological implications. There is great variability of the thoracic pedicle morphometry between the Western and the Asian population. The feasibility of thoracic pedicle screw insertion in Asians has not been fully elucidated yet. A pre-insertion radiograph was performed and surgeons were blinded to the morphometry of the thoracic pedicles. 240 pedicle screws were inserted in ten Asian cadavers from T1 to T12 using the funnel technique. 5.0 mm screws were used from T1 to T6 while 6.0 mm screws were used from T7 to T12. Perforations were detected by direct visualization via a wide laminectomy. The narrowest pedicles are found between T3 and T6. T5 pedicle width is smallest measuring 4.1 +/- 1.3 mm. There were 24 (10.0%) Grade 1 perforations and only 1 (0.4%) Grade 2 perforation. Grade 2 or worse perforation is considered significant perforation which would threaten the neural structures. There were twice as many lateral and inferior perforations compared to medial perforations. 48.0% of the perforations occurred at T1, T2 and T3 pedicles. Pedicle fracture occurred in 10.4% of pedicles. Intra-operatively, the absence of funnel was found in 24.5% of pedicles. In conclusion, thoracic pedicle screws using 5.0 mm at T1-T6 and 6.0 mm at T7-T12 can be inserted safely in Asian cadavers using the funnel technique despite having smaller thoracic pedicle morphometry.

Matched MeSH terms: Body Size/physiology
Reappraisal of the Javanese Bullfrog complex, Kaloula baleata (Müller, 1836) (Amphibia: Anura: Microhylidae), reveals a new species from Peninsular Malaysia

Chan KO, Grismer LL, Brown RM

Zootaxa, 2014;3900(4):569-80.
PMID: 25543757 DOI: 10.11646/zootaxa.3900.4.7

A new species of Narrow-mouthed frog of the genus Kaloula is described from northern Peninsular Malaysia. Kaloula latidisca sp. nov. is genetically and morphologically most similar to K. baleata and K. indochinensis but differs from those and other congeners by the unique combination of the following characters: (1) adult males SVL 49.2-56.2 mm (x̅=53.5 ± 3.0; N=4); (2) finger tips expanded into large, transversely expanded discs (disc width 2.8-3.1 mm, x̅=3.0 ± 0.1); (3) inner metatarsal tubercle large, oval, distinctly raised, slightly shorter than first toe; (4) three subarticular tubercles on fourth toe; (5) toe webbing formula: I 1-2 II 1-3 III 2-3.5 IV 4-2 V; and (6) yellow to orange irregularly shaped patch on the axillary, inguinal and posterior region of thigh.

Matched MeSH terms: Body Size
Fulltext Trap geometry in three giant montane pitcher plant species from Borneo is a function of tree shrew body size

Chin L, Moran JA, Clarke C

New Phytol, 2010 Apr;186(2):461-70.
PMID: 20100203 DOI: 10.1111/j.1469-8137.2009.03166.x

*Three Bornean pitcher plant species, Nepenthes lowii, N. rajah and N. macrophylla, produce modified pitchers that 'capture' tree shrew faeces for nutritional benefit. Tree shrews (Tupaia montana) feed on exudates produced by glands on the inner surfaces of the pitcher lids and defecate into the pitchers. *Here, we tested the hypothesis that pitcher geometry in these species is related to tree shrew body size by comparing the pitcher characteristics with those of five other 'typical' (arthropod-trapping) Nepenthes species. *We found that only pitchers with large orifices and lids that are concave, elongated and oriented approximately at right angles to the orifice capture faeces. The distance from the tree shrews' food source (that is, the lid nectar glands) to the front of the pitcher orifice precisely matches the head plus body length of T. montana in the faeces-trapping species, and is a function of orifice size and the angle of lid reflexion. *Substantial changes to nutrient acquisition strategies in carnivorous plants may occur through simple modifications to trap geometry. This extraordinary plant-animal interaction adds to a growing body of evidence that Nepenthes represents a candidate model for adaptive radiation with regard to nitrogen sequestration strategies.

Matched MeSH terms: Body Size*
Inter- and intraspecific aggression in the invasive longlegged ant (Hymenoptera: Formicidae)

Chong KF, Lee CY

J Econ Entomol, 2010 Oct;103(5):1775-83.
PMID: 21061979

The longlegged ant, Anoplolepis gracilipes (Fr. Smith) (Hymenoptera: Formicidae), is a highly invasive species that can aggressively displace other ant species. We conducted laboratory assays to examine interspecies aggression of A. gracilipes versus 15 sympatric ant species found in the urban environment and disturbed habitat in Malaysia: Monomorium pharaonis (L.), Monomorium floricola (Jerdon), Monomorium orientale Mayr, Monomorium destructor (Jerdon), Pheidole parva Mayr, Crematogaster sp., Solenopsis geminata (F.), Tapinoma indicum (Forel), Tapinoma melanocephalum (F.), Technomyrmnex butteli Forel, Dolichoderus thoracicus (Smith), Paratrechina longicornis (Latrielle), Oecophylla smaragdina (F), Camponotus sp., and Tetraponera rufonigra (Jerdon). A. gracilipes showed aggressive behavior toward all opponent species, except the smallest M. orientale. Opponent species size (body size, head width, and mandible width) was significantly correlated with A. gracilipes aggression level and mortality rate. We also found a significant positive relationship between A. gracilipes aggression level and the mortality of the opponent species. The results suggest that invasive populations of A. gracilipes would have the greatest impact on larger ant species. In addition, we examined the intraspecific aggression of A. gracilipes. We found that A. gracilipes from different localities in Malaysia showed intraspecific aggression toward one another. This finding differs from the results of studies conducted in Christmas Island earlier. Differences in the genetic variability among populations may explain these differing results.

Matched MeSH terms: Body Size
Beyond Moa's Ark and Wallace's Line: extralimital distribution of new species of Austronothrus (Acari, Oribatida, Crotoniidae) and the endemicity of the New Zealand oribatid mite fauna

Colloff MJ, Cameron SL

Zootaxa, 2014;3780:263-81.
PMID: 24871836 DOI: 10.11646/zootaxa.3780.2.3

The genus Austronothrus was previously known from three species recorded only from New Zealand. Austronothrus kinabalu sp. nov. is described from Sabah, Borneo and A. rostralis sp. nov. from Norfolk Island, south-west Pacific. A key to Austronothrus is included. These new species extend the distribution of Austronothrus beyond New Zealand and confirms that the subfamily Crotoniinae is not confined to former Gondwanan landmasses. The distribution pattern of Austronothrus spp., combining Oriental and Gondwanan localities, is indicative of a curved, linear track; consistent with the accretion of island arcs and volcanic terranes around the plate margins of the Pacific Ocean, with older taxa persisting on younger island though localised dispersal within island arc metapopulations. Phylogenetic analysis and an area cladogram are consistent with a broad ancestral distribution of Austronothrus in the Oriental region and on Gondwanan terranes, with subsequent divergence and distribution southward from the Sunda region to New Zealand. This pattern is more complex than might be expected if the New Zealand oribatid fauna was derived from dispersal following re-emergence of land after inundation during the Oligocene (25 mya), as well as if the fauna emanated from endemic, relictual taxa following separation of New Zealand from Gondwana during the Cretaceous (80 mya).

Matched MeSH terms: Body Size
Fulltext Prey Capture Ecology of the Cubozoan Carukia barnesi

Courtney R, Sachlikidis N, Jones R, Seymour J

PLoS One, 2015;10(5):e0124256.
PMID: 25970583 DOI: 10.1371/journal.pone.0124256

Adult Carukia barnesi medusae feed predominantly on larval fish; however, their mode of prey capture seems more complex than previously described. Our findings revealed that during light conditions, this species extends its tentacles and 'twitches' them frequently. This highlights the lure-like nematocyst clusters in the water column, which actively attract larval fish that are consequently stung and consumed. This fishing behavior was not observed during dark conditions, presumably to reduce energy expenditure when they are not luring visually oriented prey. We found that larger medusae have longer tentacles; however, the spacing between the nematocyst clusters is not dependent on size, suggesting that the spacing of the nematocyst clusters is important for prey capture. Additionally, larger specimens twitch their tentacles more frequently than small specimens, which correlate with their recent ontogenetic prey shift from plankton to larval fish. These results indicate that adult medusae of C. barnesi are not opportunistically grazing in the water column, but instead utilize sophisticated prey capture techniques to specifically target larval fish.

Matched MeSH terms: Body Size

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