Volume 95, Issue 5
October 1986, pages 487-639
pp 487-507 October 1986
Six new species are described:Melanagromyza erawanensis sp nov.Melanagromyza inthanonensis sp.nov.,Melanagromyza pasiae sp.nov., andMelanagromyza pasiensis sp.nov.;Tropicomyia pilosa sp.nov; andPseudonapomyza rampae sp.nov. Two new synonyms are established in the genusCerodontha, subg.Icteromyza-hirsuta Sasakawa withpiliseta (Becker) andhardyi Sasakawa withduplicata Spencer,Phytagromyza santokhi Garg from India is synonymised withPseudonapomyza atrata (Malloch).Cerodontha rishii Garg from India is resurrected from synonymy. Fourteen species are now recorded as new to Thailand, making the total now to 27.
pp 509-513 October 1986
Experiments were conducted withAnisops bouvieri as predator to study the advantages of helmet development in cyclomorphic formDaphnia cephalata King and the results were compared with another non-helmetedDaphnia similis Claus. The helmetedDaphnia cephalata avoidedAnisops bouvieri predation better than the non-helmeted formDaphnia similis. The predator selectively preys upon smaller sizedDaphnia similis than the largerDaphnia cephalata.
pp 515-524 October 1986
The 96 h LC50 value for zinc was 100 ppb. Larvae reared in 7 sublethal (1, 5, 10, 30, 50, 70, 90 ppb) and 96 h LC50 level concentrations (100 ppb) showed survival rates more than 10%, thus perfectly fitting in with definition of chronic concentration. Survival rate of larvae decreased with increase in test concentration but in the different chronic test concentrations, the overall time required for the completion of zoeal development did not differ significantly from that of control.
pp 525-532 October 1986
In vivo sub-acute physiological stress induced by phosphamidon on carbohydrate metabolism in phasic and tonic muscles of penaeid prawn,Penaeus indicus (H Milne Edwards) during acute and chronic exposure
Penaeid prawn,Penaeus indicus (H Milne Edwards), was subjected to acute (2 day) and chronic (15 day) exposure to sublethal concentration (0·2 ppm) of phosphamidon, and changes in the carbohydrate metabolism of phasic and tonic muscles were investigated. Differential patterns in carbohydrate metabolism were witnessed. The glycogen content of phasic muscle was elevated, whereas that of tonic muscle was depleted in response to acute exposure. During chronic exposure, both muscle tissues had elevated glycogen content. In general, both phasic and tonic muscles exhibited low-level of glycolysis and elevated oxidative pathway operation, leading to elevated glycogen content. Both, phasic and tonic muscle metabolisms were oriented towards conservation of carbohydrates and lesser production of organic acids during chronic exposure, as a possible adaptive metabolic mechanism of this prawn enabling it to counteract the toxic stress imposed by phosphamidon.
pp 533-537 October 1986
Changes in the nitrogen metabolic profdes of midgut gland, muscle and gill tissues were studied, following the exposure ofPenaeus indicus to acute (2 day) and chronic (10, 20 and 30 day) exposure to sublethal concentration (0–2 ppm) of phosphamidon. The proteolytic activity of phosphamidon exposed prawn tissues was significantly elevated. All the phosphamidon exposed prawn tissues showed efficient mechanisms of ammonia detoxification in the chronically exposed prawns when compared to acutely exposed prawns. The survivability of these prawns in the polluted habitats might be due to the operation of compensatory adaptive mechanisms in the metabolic profdes such as increased biosynthesis of different kinds of proteins and also the detoxification and transformation of ammonia, the toxic nitrogenous end product of aquatic organisms.
pp 539-547 October 1986
The snailMorula granulata (Duclos) survived the starvation stress over a period of 30 days but 50% mortality occurred on the 70th day. The changes in the level and content of different biochemical constituents viz carbohydrates, glycogen, free sugars, protein, total ninhydrin positive substances and lipids were investigated in foot, gonad digestive gland complex and viscera of the animal at intervals of 10 days up to 70 days. All these biochemical constituents (both level and content) were found to decrease with the period of starvation showing their utilisation except total ninhydrin positive substances which exhibited an increase. Of all the 3 tissues, the gonad digestive gland complex was affected most during starvation. ‘Lipid-oriented’ metabolism was observed in this animal showing maximum utilisation of lipids during starvation. Respiratory studies revealed a decreased pattern of oxygen consumption with increasing period of starvation when calculated per snail or per tissue weight. The recalculated intercept values (a) also showed a decreasing trend when exposed to starvation.
pp 549-555 October 1986
A year round study was conducted in Trivandrum city during the period of March 1984 to February 1985 to elucidate the relation between certain physico-chemical factors and seasonal density ofMansonia larvae (Culicidae: Diptera).Mansonia uniformis was found to be the predominant species during this period, whereasMansonia annulifera was less than 10% of the totalMansonia collected. The period of high prevalence was found to be January–March. Out of the 6 physico-chemical factors studied Na+, K+, and pH showed statistically significant correlation with the larval density, while Ca++, Mg++ and rainfall showed no significant relation.
pp 557-560 October 1986
Relative performance of morphologically indistinguishable and phylogenetically closely related forms ofDrosophila was assessed in two different media. The flies performed better in media with molasses than in media with fructose. There were significant differences in the ability of these strains to exploit a similar sugar resource suggesting differences in the adaptedness of these forms. The implications of these findings are discussed.
pp 561-566 October 1986
Studies conducted for a period of one year (from April 1982 to March 1983) revealed that temperature and relative humidity play a significant role on incubation period, pupal period, emergence percentage, adult longevity and fecundity of uzi fly,Tricholyga bombycis. Correlation between temperature, humidity and certain developmental stages is also established.
pp 567-577 October 1986
The differential distribution of cones in the various regions of the retina of the fishNemipterus japonicus (Bloch) was studied. In tangential section two types of cones are observed viz single and double cones, double cones being greater in number than single cones. Of the total cones, double cones constitute 86% while single cones constitute only 14%. In most of the retinal regions, cones are in the square mosaic pattern. The temporal region has greater number of cones than the other retinal regions which were studied. The correlation coefficients for the temporal region with all other regions are invariably positive.
The test shows that there is no significance between the eyes whereas significance is observed among the various retinal regions. The pattern of cone arrangement agrees with the bottom dwelling habit of the fish. The shape of the eye is modified by being slightly ablong with comparatively longer anterio-posterior axis. The retinal cup is more hollow at the temporal region than at the nasal region.
pp 579-586 October 1986
Laboratory measurements of physiological energetics were coupled with the field observations on time budget/energy intake ofMegachile nana andMegachile flavipes to estimate the daily energy budget. The energy budget varied from one day to another, and crop to crop. In general, the foraging profitability/attractibility was in the following order for both the species:Parkinsonia aculeata> Medicago sativa> Trifolium alexandrium. The studies revealed the competitive superiority ofParkinsonia aculeata overMedicago sativa andTrifolium alexandrium.
pp 587-593 October 1986
Ethyl methanesulphonate (0·75%) was mixed with food (1∶9) and fed to developing F1 (Oregon-K+/dumpy black cinnabar, dp b cn) individuals in second one-third part (54–86 h after egg deposition) of larval life, at 25±1°C, for inducing recombination in males ofDrosophila melanogaster. In control and 0·75% ethyl methanesulphonate experiments, pooled test cross progeny comprised 3475 and 13887 flies, respectively, out of which 9 and 236 were recombinants. From these, 9 and 192 recombinants were further test-crossed and 55·5% and 87·0% were verified, respectively. Non-reciprocal recombination was observed indp-b but not inb-cn region with 0·75% ethyl methanesulphonate as evidenced by high frequency of +b cn male recombinants over its complementary classdp ++. Majority of the +b cn male recombinants verified did not produce in their test cross progeny the two phenotypes (+b cn anddp b cn) in expected 1∶1 ratio contrary to +b cn female recombinants, suggesting influence of cytoplasm in transmission of recombinant (+b cn) phenotype from male.
pp 595-603 October 1986
The sensory receptors of the flagellum ofApis florea were studied with simple and transmission electron microscopy. The antenna consists of scape, pedicel and 10 segmented flagellum. Scape and pedicel have only feather like hairs and no structures like the setae or sensillae of the flagellum. The first two segments of the flagellum were covered with setae. The distribution and population of sensilla trichodea, sensilla placodea and sensilla basiconica were determined. Sensilla trichodea were found in maximum numbers and were present on all the flagellar segments. Sensilla placodea and sensilla basiconica were present on 8 distal segments. Transmission electron microscopy studies revealed that the surface of the shaft of sensilla trichodea is serially striated having small permeable points probably indicating pores. The lumen of the sensillum is filled with many dendrites and the dendrites are enclosed in the dendritic sheath.
pp 605-612 October 1986
Self and social play of 29 rhesus monkeys were observed in a free-ranging group situation for 6 months. Subjects of various age-sex classes were observed by focal animal and one-zero sampling. Frequencies for 5 categories of play were analyzed in a 3 way factorial analysis of variance. Age and frequencies of play were found to be inversely related. Analysis also revealed that except during infancy, females played more than male subjects. Among categories, self play and non-contact mutual play were dominant forms than those involving physical contact of either or both partners. However, it was also influenced by age, as the preference shifts from self play to non-contact mutual play in a developmental perspective. Among adult monkeys, the occurrence of play was least. Obtained results have been interpreted in terms of ontogenetic and situational variables. Rhesus monkeys preferred peers in social play than youngers and elders. However, adolescent/subadult and adult animals played with younger animals.
pp 613-616 October 1986
An extremely low egg output, almost approaching zero level, and with no sign of viability, occur inEarias vittella (F.) when the females are coupled for mating with antennectomised males or if both sexes paired for coition are wingless. However, sexual union arranged between normal females and males whose both wings or only fore or hindwings are excised facilitates these insects to deposit fertile eggs whose number, however, always remains markedly lower (more so when the males in the breeding pairs are without hindwings) in comparison to that recorded for mated females in pairs where both sexes are normal.
pp 617-622 October 1986
Mahua oil cake, a derivative from the plantBassia latifolia, is extensively used as fish toxicant cum pond manure in inland aquaculture systems of India. Saponin, one of the haemolytic components of mahua oil cake, has a lethal effect on fishes and other organisms. In the present investigation,Heteropneustes fossilis—an air-breathing catfish andCyprinus carpio—a carp, were treated with mahua oil cake and their haematological indices were evaluated. The effect was fatally critical with gradual and complete shrinkage of erythrocytes, followed by ultimate haemolysis of cells, and significant reduction of the values of haematocrit, haemoglobin concentration and red cell count.
pp 623-628 October 1986
Histochemical method for non-specific esterases has been applied to cercariae belonging to 4 different trematode groups viz Monostome, Amphistome, Xiphidio and Echinostome. Various structures containing esterases revealed positive reactions to the standard method and are visualized in simple whole mount preparation. Different degrees of non-specific esterase activities were observed in the nervous and the excretory systems, suckers and sub-tegumentary cells. In general, nervous systems of cercariae are composed of a pair of cerebral ganglia connected to each other by a transverse commissure to form a cerebral complex. These give off 3 pairs of anterior longitudinal and 3 pairs of posterior longitudinal nerve cords. Simultaneously nervous systems of redia of monostome cercaria have also been focused in the present study.
pp 629-639 October 1986
The von Bertalanffy parameters of growth inPenaeus indicus are estimated as L∞=218·9 mm,K=2·0 per year, andt0=0·01 year in females and 227·2 mm, 1·8 per year and −0·0729 year, respectively in males. The instantaneous rates of mortality are estimated asZ=9·42,M=3·30 andF=6·12 in females and 12·73, 2·90 and 9·83, respectively in males. Various morphometric and length-weight relationships are worked out. At the current rate of fishing, the yield in weight per recruit is 23·05 g in females and 31·74 g in males. There is scope to increase the yield of this species by increasingF (i.e. effort).