Population growth, trophic level, and some aspects of reproductive biology of two congeneric archer fish species, Toxotes chatareus and Toxotes jaculatrix, collected from Johor coastal waters, Malaysia, were studied. Growth pattern by length-weight relationship (W=aL(b)) for the sexes differed, and exhibited positive allometric growth (male, female and combined sexes of T. chatareus; female and combined sexes of T. jaculatrix) and isometric growth (male samples of T. jaculatrix only). Trophic levels of both species were analyzed based on 128 specimens. The results show that, in both species, crustaceans and insects were the most abundant prey items, and among crustaceans the red clawed crab Sesarma bidens and Formicidae family insects were the most represented taxa. The estimated mean trophic levels for T. chatareus and T. jaculatrix were 3.422+/-0.009 and 3.420+/-0.020, respectively, indicating that they are largely carnivores. Fecundity of T. chatareus ranged from 38 354 to 147 185 eggs for females with total length ranging from 14.5 to 22.5 cm and total body weight from 48.7 to 270.2 g, and T. jaculatrix 25 251 to 150 456 eggs for females with total length ranging from 12.2 to 23.0 cm and total body weight from 25.7 to 275.0 g. Differences in values of gonadosomatic and hepatosomatic indexes calculated for both species in this study may have resulted from uneven sample size ranges.
We describe a new species of Leptolalax from Gunung Mulu National Park in eastern Sarawak, Malaysian Borneo. The new species had been assigned to Leptolalax dringi and Leptolalax gracilis in the past. It is shown to differ from both these species and from all other species of the genus by a unique combination of morphological characters including large body size, rounded snout, interorbital distance being smaller than width of upper eyelid, bipartite subgular vocal sac in males, basal toe webbing, shagreened skin with tiny tubercles on dorsum and dorsal side of head, angled supratympanic fold, small pectoral glands, absence of supraaxillary glands and ventrolateral glandular ridges, spotted venter, advertisement call consisting of long series of 8-289 notes, each composed of three or four pulses, and dominant frequency at 7225-9190 Hz, with prominent frequency modulation.
The higher-level taxonomy of the stingrays (Dasyatidae) has never been comprehensively reviewed. Recent phylogenetic studies, supported by morphological data, have provided evidence that the group is monophyletic and consists of four major subgroups, the subfamilies Dasyatinae, Neotrygoninae, Urogymninae and Hypolophinae. A morphologically based review of 89 currently recognised species, undertaken for a guide to the world's rays, indicated that most of the currently recognised dasyatid genera are not monophyletic groups. These findings were supported by molecular analyses using the NADH2 gene for about 77 of these species, and this topology is supported by preliminary analyses base on whole mitochondrial genome comparisons. These molecular analyses, based on data generated from the Chondrichthyan Tree of Life project, are the most taxon-rich data available for this family. Material from all of the presently recognised genera (Dasyatis, Pteroplatytrygon and Taeniurops [Dasyatinae]; Neotrygon and Taeniura [Neotrygoninae]; Himantura and Urogymnus [Urogymninae]; and Makararaja and Pastinachus [Hypolophinae]), are included and their validity largely supported. Urogymnus and the two most species rich genera, Dasyatis and Himantura, are not considered to be monophyletic and were redefined based on external morphology. Seven new genus-level taxa are erected (Megatrygon and Telatrygon [Dasyatinae]; Brevitrygon, Fluvitrygon, Fontitrygon, Maculabatis and Pateobatis [Urogymninae], and an additional three (Bathytoshia, Hemitrygon and Hypanus [Dasyatinae]) are resurrected from the synonymy of Dasyatis. The monotypic genus Megatrygon clustered with 'amphi-American Himantura' outside the Dasyatidae, and instead as the sister group of the Potamotrygonidae and Urotrygonidae. Megatrygon is provisionally retained in the Dasyatinae pending further investigation of its internal anatomy. The morphologically divergent groups, Bathytoshia and Pteroplatytrygon, possibly form a single monophyletic group so further investigation is needed to confirm the validity of Pteroplatytrygon. A reclassification of the family Dasyatidae is provided and the above taxa are defined based on new morphological data.
The genus Anipocregyes Breuning, 1939 is reviewed. Cristipocregyes rondoni Breuning, 1965, Metipocregyes rondoni Breuning, 1965, and Mesosa (Perimesosa) seminivea Breuning, 1965 are transferred to the genus Anipocregyes, and Setomesosa rondoni Breuning, 1968 is synonymized with A. seminivea comb. nov. As a result, two genera, Cristipocregyes Breuning, 1965 and Setomesosa Breuning, 1968, are synonymized with Anipocregyes. Metipocregyes rondoni Breuning, 1965 becomes a secondary homonym and Anipocregyes albifrons nom. nov. is proposed as a replacement name. Anipocregyes kawakamii sp. nov. and A. wakabayashii sp. nov. are described from Borneo. All the seven known species of Anipocregyes are illustrated with their male genitalia (except for A. laosensis) and a key to the species is provided.
Six new species of marpissoid jumping spiders from Sarawak, Borneo, are described in the new genus Tisaniba Zhang & Maddison. They are the type species, T. mulu Zhang & Maddison sp. nov., as well as the species T. bijibijan Zhang & Maddison sp. nov., T. dik Zhang & Maddison sp. nov., T. kubah Zhang & Maddison sp. nov., T. selan Zhang & Maddison sp. nov., and T. selasi Zhang & Maddison sp. nov. The spiders are small and brown to black, living in leaf litter in the tropical forest. Phylogenetic analyses based on 28s and 16sND1 genes indicate that they are a distinctive group within the marpissoids. Diagnostic illustrations and photographs of living spiders are provided for all species.
One species of lace bug Cochlochila bullita Stål (Heteroptera: Tingidae) was found heavily infested Orthosiphon aristatus Blume Miq., an important medicinal plant in Malaysia. A morphological re-description of C. bullita was done in order to facilitate the identification of this oligophagous insect pest. Five variables, body length and width, antenna length, tibia length and head width were measured from 15 samples from each stage. Among these variables, body length and width were used to construct the ratio for species identification; while body lengths with the other three variables were used to distinguish the nymphs from each developmental stage. The measurements of four traits except the antenna length showed significant differences between the development stages. And thus suggest the body width, tibia length and head width were suitable parameters used to distinguish the nymphal stages. However, the result on the growth factor showed only the sizes of the head followed a more constant growth rate with growth ratios (1.21-1.39) lie between the Dyar's ratio. Body length and width ratio for the adult female and male was 1.51 +/- 0.00 and 1.59 +/- 0.01, respectively. These data are pertinent for identifying developmental stages and to distinguish the species of the lace bug.
Phaenandrogomphus safei is described from a male from the Kalabakan Forest Reserve, Sabah, Malaysian Borneo. It is the first species of Phaenandrogomphus to be recorded from Borneo. Onychogomphus treadawayi, known from Busuanga Island in the Palawan region of the Philippines, is transferred to Phaenandrogomphus.
A new species Uroballus koponeni sp. n. (♀) from Malaysia (Borneo) is diagnosed, illustrated and described. The genus is unusual for jumping spiders in having extremely long spinnerets.
The genus Cryptopsocus Li, 2002 is synonymized with Trichadenotecnum Enderlein, 1909. The type species of Crypto-psocus, T. cynostigmus (Li, 2002) n. comb., is considered to be a close relative of T. marginatum New & Thornton, 1976. These species cannot be assigned to any species group previously established in Trichadenotecnum so that the marginatum species group is here proposed for them. Three new species belonging to this species group are described: T. tigrinum and T. sharkeyi from Thailand and T. sabahense from Sabah, Malaysia. The phylogenetic position of the marginatum group is discussed using morphological data.
In general, demand feeding devices are equipped with a mechanical trigger switch. Such a switch is not suitable for
juvenile fish with a small body size, because the body weight is insufficient to trigger the feeder. An infrared light
sensor that does not require the fish to push a feeder switch is more suitable for small fish. The brown-marbled grouper
Epinephelus fuscoguttatus is an important fish species in Southeast Asia. The purpose of this study was to compare the
growth rates (GRs) of brown-marbled grouper juveniles reared using customised demand feeding devices with an infrared
light sensor (the infrared light demand feeder (IRDF) group) and automatic feeding devices (the automatic feeder (AF)
group). The results indicated that GRs of standard lengths and body weights showed no significant differences using
one-way analysis of variance; however, the standard length of the IRDF group showed a tendency of a higher GR than
the AF group. Although the feed conversion ratio (FCR) also showed no significant difference, the FCR of the IRDF group
was more efficient, indicating that the IRDF group yielded a more desirable FCR. These results indicate that IRDF can be
used in the culture of brown-marbled grouper juveniles. In view of the working schedule of the fish farm staff, IRDF are
superior to other feeding devices, because they are less labour-intensive than usual tasks. We conclude that IRDF is a
useful feeding system for aquaculture.
Eight species of armored spiders belonging to two families, Pacullidae Simon, 1894 and Tetrablemmidae O. Pickard-Cambridge, 1873, are reported from Singapore. Five species are documented as new to science: Paculla bukittimahensis Lin & Li, sp. n. (male and female), Paculla globosa Lin & Li, sp. n. (male and female), Ablemma malacca Lin & Li, sp. n. (male and female), Singaporemma lenachanae Lin & Li, sp. n. (male and female), and Sulaimania brevis Lin & Li, sp. n. (male). The three known species are Brignoliella besutensis Lin, Li & Jäger, 2012, Brignoliella michaeli Lehtinen, 1981, and Singaporemma singulare Shear, 1978, of which the female of Brignoliella besutensis is described for the first time. For comparison, types of Singaporemma adjacens Lehtinen, 1981 from Vietnam, Singaporemma halongense Lehtinen, 1981 from Vietnam, Singaporemma singulare from Singapore and Sulaimania vigelandi Lehtinen, 1981 from Malaysia are studied and photographed.
The Oriental pselaphine genus Horniella Raffray, 1905 (tribe Tyrini: subtribe Somatipionina) is redefined and revised. Twenty-five new species are described: H. centralis Yin & Li, sp. n., H. confragosa Yin & Li, sp. n., H. dao Yin & Li, sp. n., H. hongkongensis Yin & Li, sp. n., H. nakhi Yin & Li, sp. n., H. schuelkei Yin & Li, sp. n., H. sichuanica Yin & Li, sp. n., H. simplaria Yin & Li, sp. n., and H. tianmuensis Yin & Li, sp. n. from China, H. himalayica Yin & Li, sp. n. from Nepal and North India, H. asymmetrica Yin & Li, sp. n., H. burckhardti Yin & Li, sp. n., H. intricata Yin & Li, sp. n., H. kaengkrachan Yin & Li, sp. n., H. khaosabap Yin & Li, sp. n., H. loebli Yin & Li, sp. n., H. phuphaman Yin & Li, sp. n., H. prolixo Yin & Li, sp. n., and H. schwendingeri Yin & Li, sp. n. from Thailand, H. philippina Yin & Li, sp. n. from the Philippines, H. awana Yin & Li, sp. n., H. gigas Yin & Li, sp. n., H. pilosa Yin & Li, sp. n., and H. smetanai Yin & Li, sp. n. from Malaysia, and H. cibodas Yin & Li, sp. n. from Indonesia. The two previously described species, H. hirtella Raffray, 1901 (type species) from Sri Lanka and H. falcis Yin & Li, 2010 from China are redescribed, and a lectotype is designated for H. hirtella. Illustrations of habitus and important diagnostic features, an identification key, and distributional maps for all species are provided. Eleven unidentified species represented only by females are left unnamed. Illustrations of the habitus and the genital complex, and label data of these species are given to facilitate future study. All available data indicates that species of Horniella typically inhabit leaf litter of various kinds of forests, and can be most efficiently collected by sifting and use of Winkler-Moczarski extractors.
Tmesiphodimerus Coulon and Yin, new genus (Pselaphitae: Tmesiphorini) is proposed for T. sinensis Yin and Coulon, new species from Hainan, South China (type species), and T. malaysianus Coulon and Yin, new species from Perak, West Malaysia. The new taxa are described, with their major diagnostic features illustrated. The taxonomic placement of Tmesiphodimerus is discussed.
Tropical ectotherms are generally believed to be more vulnerable to global heating than temperate species. Currently, however, we have insufficient knowledge of the thermoregulatory physiology of equatorial tropical mammals, particularly of small diurnal mammals, to enable similar predictions. In this study, we measured the resting metabolic rates (via oxygen consumption) of wild-caught lesser treeshrews (Tupaia minor, order Scandentia) over a range of ambient temperatures. We predicted that, similar to other treeshrews, T. minor would exhibit more flexibility in body temperature regulation and a wider thermoneutral zone compared with other small mammals because these thermoregulatory traits provide both energy and water savings at high ambient temperatures. Basal metabolic rate was on average
1.03 ± 0.10
mL O2 h-1 g-1, which is within the range predicted for a 65-g mammal. We calculated the lower critical temperature of the thermoneutral zone at 31.0°C (95% confidence interval: 29.3°-32.7°C), but using metabolic rates alone, we could not determine the upper critical temperature at ambient temperatures as high as 36°C. The thermoregulatory characteristics of lesser treeshrews provide a means of saving energy and water at temperatures well in excess of their current environmental temperatures. Our research highlights the knowledge gaps in our understanding of the energetics of mammals living in high-temperature environments, specifically in the equatorial tropics, and questions the purported lack of variance in the upper critical temperatures of the thermoneutral zone in mammals, emphasizing the importance of further research in the tropics.
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.
This study examined the fecundity, oviposition, nymphal development and longevity of field-collected samples of the tropical bedbug, Cimex hemipterus (Fabricius) (Hemiptera: Cimicidae). Under environmental conditions of 26+/-2 degrees C, 70 +/- 5% relative humidity and a 12-h photoperiod, with bloodmeals provided by a human host, six strains of tropical bedbug had a fecundity of up to 50 eggs per lifetime, over 11-14 oviposition cycles. Increased feeding frequency improved fecundity. After feeding and mating, adult females normally took 2-3 days to produce a first batch of eggs. The oviposition period lasted 2-7 days before cessation of the oviposition cycle. The egg incubation period usually lasted 5-7 days before the emergence of first instars. The nymphs underwent five stadia (the first four of which each took 3-4 days, whereas the last took 4-5 days) before becoming adults at a sex ratio of 1 : 1. More than five bloodmeals were required by the nymphs to ensure a successful moult. Unmated adults lived significantly longer than mated adults (P < 0.05). Unmated females lived up to almost 7 months, but the longevity of mated males and females did not differ significantly (P > 0.05).
The genus Doryscus Jacoby, 1887 is revised. Twelve new species are described: D. indochinensis sp. nov. from China (Yunnan), India, Laos, Thailand, Vietnam; D. krausi sp. nov. from Laos and Thailand; D. kubani sp. nov., from China (Yunnan); D. geiseri sp. nov. from Singapore and Thailand; D. nepalensis sp. nov. from Bhutan, north India, and Nepal; D. luzonensis sp. nov., and D. mindanaoensis sp. nov. from Philippines; D. barclayi sp. nov., D. boreri sp. nov., D. javanensis sp. nov., and D. sumatrensis sp. nov. from Indonesia; D. wangi sp. nov. from East Malaysia (Sabah). Doryscus chujoi Takizawa, 1978 and D. varians (Gressitt & Kimoto, 1963) are removed from synonymy with D. testaceus Jacoby, 1887. Doryscus nigricollis Jiang, 1992 and D. marginicollis Jiang, 1992 are regarded as junior synonyms of D. varians (Gressitt & Kimoto, 1963). A lectotype is designated for Doryscus testaceus Jacoby, 1887.
The uniquely enlarged noses of male proboscis monkeys are prominent adornments, and a sexually selected male trait. A recent study showed significant correlations among nose, body, and testis sizes and clear associations between nose size and the number of females in a male's harem. However, to date, the analyses of other common male traits, i.e., canines, are lacking. Whereas male nose size had a positive correlation with body size, we unexpectedly found a negative correlation between body and canine sizes. We explain this by an interaction between sexual and natural selection. Larger noses in males may interfere with the use of canines, thereby reducing their effectiveness as weapons. Additionally, longer canines are opposed by natural selection because the larger gape it imposes upon its bearer reduces foraging efficiency, particularly in folivores. This unique case of decoupling of body and canine size reveals that large canines carry an ecological cost.
The taxonomy of poorly known Mesagraecia Ingrisch, 1998 is reviewed. A new species of Mesagraecia spine-headed katydid (Conocephalinae: Agraeciini) is described from Bukit Larut, Perak, Peninsular Malaysia: Mesagraecia larutensis sp. n. A key to species is also presented.