Predator naïve minnows respond to their conspecific alarm substance but not the odour from a non-native predator

When exposed to predator cues, ostariophysan fishes exhibit short-term anti-predator behavioural responses in order to minimise predation risk. Non-native predator cues are, however, likely to elicit poor behavioural responses in native prey fishes. This study investigated whether chubbyhead barb Enteromius anoplus, a native freshwater minnow in South Africa, had the innate ability to recognise and respond to largemouth bass Micropterus salmoides, a non-native piscivore. This was experimentally evaluated by investigating behavioural responses to both the non-native predator's odour and damage-released conspecific alarm substance (CAS). Chubbyhead barbs did not exhibit any behavioural response to largemouth bass odour both before and after exposure to CAS. This suggests that the chubbyhead barbs likely lacked the innate ability to recognise the non-native largemouth bass predator kairomones. By comparison, exposure to CAS was associated with significant behavioural responses, with chubbyhead barbs shifting from free-swimming to hovering, and frequent use of refugia. This suggests that despite ineffective response to non-native largemouth bass odour, chubbyhead barbs responded to general predator attack. Overall, this study suggests the potential for non-native largemouth bass to induce negative consumptive effects on chubbyhead barbs due to their inability to identify non-native predator's odour. In addition, nonconsumptive effects are likely due to altered activities in response to predator attack.     

Interrelationships and evolution of the east Asian grass lizards, Takydromus (Squamata: Lacertidae)

The east Asian lacertid lizard genus, Takydromus , is well-defined but its relationships to other primitive Palaearctic lacertids are still uncertain and, although it has similarities to the lower Miocene Miolacerta, Takydromus does not appear to be identical with this. The 16 or 17 recognizable species are reviewed and a key provided for their identification; the remaining area of uncertainty about species boundaries is the Takydromus sexlineatus group in Assam. A phylogeny for Takydromus is estimated using a data set of 35 morphological characters drawn from external features, skeleton and soft-parts. There are two main constituent clades which may be informally recognized as Takydromus s.s. and Platyplacopus. Platyplacopus is subtropical and perhaps relict, whereas Takydromus ranges from temperate to tropical areas. The two clades have different ranges of eggs per clutch. In both of them, elongate forms that climb extensively in flimsy vegetation have evolved and have independently acquired similar features that confer performance advantages in this situation. Interestingly, the order of assembly of tliese features is markedly different.     

Mitochondrial DNA phylogeography reveals a west–east division of the northern grass lizard (Takydromus septentrionalis) endemic to China

We sequenced partial mitochondrial DNA from the cytochrome b gene (1143 bps) for 385 northern grass lizards (Takydromus septentrionalis) from 14 mainland and 14 island populations covering almost the lizard’s entire range to examine the influence of geographic barriers (mountain ranges and water bodies) on the diversification of lineages. Phylogenetic analyses revealed a detailed distribution of three evolutionary lineages (W, E and G). Lineage G included individuals exclusively from Guiyang, in the south‐western distributional limit. Lineage W included individuals from the central and western parts of the lizard’s range on the mainland. Lineage E included individuals from East China, both on the mainland and on islands in the East China Sea. Haplotypes from lineages W and E were co‐distributed in Chuzhou and Chibi. The averaged pairwise distance of 6.23% between these lineages indicated a Miocene‐Pliocene lineage‐split. Lineage E was further subdivided to three sublineages: E1 and E2 comprised of haplotypes from the Zhoushan Islands, and E3 included haplotypes from the eastern mainland, the Zhoushan Islands and two islands south of the Zhoushan Islands. Lineages W and E showed evidence of demographic extensions. The isolation caused by the last transgression (0.01 Ma) has not yet led to a significant genetic differentiation between mainland and island populations in East China. However, divergence among some small islands may be driven by the restriction of migration and genetic drift.     

Isolation and characterization of 12 tetra‐repeated microsatellite loci from the Formosan grass lizard (Takydromus formosanus)

Twelve tetra‐repeated microsatellite loci were developed for the island‐endemic grass lizard Takydromus formosanus (Squamata: Lacertidae). We characterized these loci by genotyping 51 individuals sampled from six localities. The number of alleles per locus ranged between 12 and 23, whereas the observed heterozygosity ranged between 0.686 and 0.941. None of these loci showed gametic disequilibrium or sex linkage. With such high polymorphism, we believe that these loci should be suitable for fine‐scaled analysis of population structure, hybridizations or individual identification of grass lizards.     

Identification of 2-phenylethanol with a rose-like odor from anal sac secretions of the small Indian mongoose (Herpestes auropunctatus)

The small Indian mongoose (Herpestes auropunctatus) is an invasive species in Okinawa and Amami-Oshima, Japan. Major strategies for their eradication have been the use of baited traps, which suffer from decreasing efficiency with declining populations and the bycatch of native animals. To address these concerns, mongoose-specific lures are required. In this study, we aimed to identify species- and/or sex-specific compounds from anal sac secretions of small Indian mongooses. Volatile compounds emitted from male and female mongoose anal sac secretions were analyzed by thermal desorption-gas chromatography-mass spectrometry. In addition to several fatty acids, 2-phenylethanol was identified as a minor compound, which is uncommon in mammalian secretions but a dominant odorant in roses. Female samples emitted higher levels of 2-phenylethanol than male samples did. These findings indicate that 2-phenylethanol is a female-specific volatile compound of anal sac secretions in small Indian mongooses, and it may be useful as an ingredient of mongoose-specific scent lures.     

Know thy enemy: Behavioural response of a native mammal (Rattus lutreolus velutinus) to predators of different coexistence histories

Abstract Predation is recognized as a major selective pressure influencing population dynamics and evolutionary processes. Prey species have developed a variety of predator avoidance strategies, not least of which is olfactory recognition. However, within Australia, European settlement has brought with it a number of introduced predators, perhaps most notably the red fox (Vulpes vulpes) and domestic cat (Felis catus), which native prey species may be unable to recognize and thus avoid due to a lack of coexistence history. This study examined the response of native Tasmanian swamp rats (Rattus lutreolus velutinus) to predators of different coexistence history (native predator‐ spotted‐tail quoll (Dasyurus maculatus), domestic cats and the recently introduced red fox). We used an aggregate behavioural response of R. l. velutinus to predator integumental odour in order to assess an overall behavioural response to predation risk. Rattus lutreolus velutinus recognized the integumental odour of the native quoll (compared with control odours) but did not respond to either cat or fox scent (compared with control odur). In contrast, analyses of singular behaviours resulted in the conclusion that rats did not respond differentially to either native or introduced predators, as other studies have concluded. Therefore, measuring risk assessment behaviours at the level of overall aggregate response may be more beneficial in understanding and analysing complex behavioural patterns such as predator detection and recognition. These results suggest that fox and cat introductions (and their interactive effects) may have detrimental impacts upon small native Tasmanian mammals due to lack of recognition and thus appropriate responses.     

A native predator utilising the invasive brown marmorated stink bug,Halyomorpha halys (Hemiptera: Pentatomidae) as a food source

The nest provisions of a native predator species Bicyrtes quadrifasciata (Say) (Hymenoptera: Crabronidae) were surveyed and examined for the presence of nymphs of Halyomorpha halys, which is an invasive pest of many economically important agricultural crops in the U.S.A. We found 96% of the nest provisions of B. quadrifasciata were H. halys indicating the potential of B. quadrifasciata in biocontrol of this pest. Potential of B. quadrifasciata in regulating population dynamics of H. halys is discussed.     

Suitability of native North American Rutaceae to serve as host plants for the Asian citrus psyllid (Hemiptera: Liviidae)

The Asian citrus psyllid, Diaphorina citri Kuwayama, a vector of citrus huanglongbing, is now present in all citrus‐producing states in the USA and Mexico. In addition to citrus, the insect can reproduce on several other plant species in the Rutaceae family; orange jasmine (Murraya spp.) and curry leaf (Bergera koenigii) are among its preferred hosts. There are several indigenous Rutaceae species in North America, and some are popular ornamentals. A study was therefore initiated to determine the suitability of some of these plants for feeding and development of the psyllid in choice and no‐choice experiments. D. citri was found to reproduce successfully on Choisya ternata, C. arizonica and Helietta parvifolia in no‐choice tests, but preferentially selected orange jasmine and curry leaf for feeding and reproduction, in choice tests. On Amyris madrensis, A. texana and Zanthoxylum fagara, adult psyllids laid eggs which hatched, but no successful nymphal development was recorded beyond the first instars. No oviposition was recorded on Esenbeckia berlandieri, Ptelea trifoliata and Casimiroa tetrameria, although adult psyllids were able to survive on these species for several days. Results showed that C. ternata, C. arizonica and H. parvifolia can serve host plants of D. citri and this constitutes the first report of these plants serving as host for D. citri. The findings of the present study suggest that native rutaceous host plants can serve as host plants and thus affect D. citri population dynamics and the epidemiology of Huanglongbing, the deadly citrus greening disease whose pathogen is vectored by D. citri. Thus, area‐wide management of this pest also should target these riparian habitats where these host plants are present with D. citri biological control agents for sustainable management of this pest.     

Effects of diet on development of Podisus nigrispinus (Dallas) (Het., Pentatomidae), a predator of the cotton leafworm

Abstract:  The effects of diet on development of Podisus nigrispinus (Dallas) (Het., Pentatomidae) were studied at 25°C, relative humidity of 60 ± 10%, and photoperiod of 14 h light : 10 h dark. Development times of P. nigrispinus nymphs were similar when fed with third or fifth instar larvae of cotton leafworm ( Alabama argillacea Hübner) (Lep., Noctuidae) or Tenebrio molitor L. (Col., Tenebrionidae). When fed with housefly larvae ( Musca domestica L.) (Dipt., Muscidae) or artificial diet, the predator had a longer development time. Independent of diet, instar or sex, the females of P. nigrispinus showed a longer longevity than the males. The total survival of the nymphal stage, on the different diets, varied from 22.46 (fed with housefly) to 77.33% (fed with T. molitor larvae). P. nigrispinus males were heavier when fed with third or fifth instar cotton leafworm larvae than when fed with artificial diet. The weight of the females varied from 37.91 (with artificial diet) to 64.68 mg (with fifth instar cotton leafworm larvae). Independently of the diet, newly emerged females of P. nigrispinus were heavier than the males. Females of P. nigrispinus which were fed with fifth instar cotton leafworm larvae had heavier ovaries than those fed other diets.     

Food consumption does not affect the preferred body temperature of Yarrow's spiny lizard (Sceloporus jarrovi)

When animals consume less food, they must reduce their body temperature to maximize growth. However, high temperatures enhance locomotion and other performances that determine survival and reproduction. Therefore, thermoregulatory behaviors during different metabolic states reveal the relative importance of conserving energy and sustaining performance. Using artificial thermal gradients, we measured preferred body temperatures of male spiny lizards (Sceloporus jarrovi) in fed and fasted states. Both the mean and maximal body temperatures (33° and 35 °C, respectively) were unaffected by metabolic state. This finding suggests that the benefits of foraging effectively, evading predators, and defending territory outweigh the energetic cost of a high body temperature during fasting.     

Volatile chemical composition does not support a native status of the cryptogenic Bupleurum fruticosum (Apiaceae) in peninsular Italy

Cryptogenic (or doubtfully native) species could have relevant implications in biogeography and in nature conservation. Bupleurum fruticosum is native in Sicily, Sardinia, and Liguria, whereas the single Tuscan population is considered cryptogenic. Given its pharmacological activity, several studies investigated the essential oil composition of this species, but an analysis of geographic pattern of the chemical composition was never performed. In the present study, the essential oil composition of the Tuscan population was investigated for the first time, and a comparison with other populations from literature was performed in order to provide useful data to disentangle its cryptogenic status. Our results highlight a major similarity of plants from Tuscany with geographically distant populations from Portugal and France, whereas other Italian populations show a very different chemical composition. These results do not support a native status of Tuscan population, suggesting an ancient human introduction. Our analysis also revealed a high percentage of (Z)-β-ocimene in stems of plants from Tuscany.     

The nectar alkaloid, gelsemine, does not affect offspring performance of a native solitary bee, Osmia lignaria (Megachilidae)

Abstract.  1. The ecology and evolution of foliar-feeding insects are thought to be closely tied to plant secondary compounds. Although secondary compounds are also abundant in floral nectar, their role in mediating pollinator preference and performance remains relatively unexplored.
2. This study tested the effects of an alkaloid, gelsemine, found in the nectar of Carolina jessamine ( Gelsemium sempervirens L., Loganiaceae), on the performance of a native solitary bee ( Osmia lignaria lignaria Say, Megachilidae). Nectar gelsemine reduces visits from pollinators, including O. lignaria lignaria , and gelsemine is toxic to vertebrates and possibly non-native honey bees ( Apis mellifera L., Apidae). To test the hypothesis that the deterrent effects of nectar gelsemine reflect negative consequences for pollinator performance, O. lignaria lignaria offspring provisions were supplemented with nectar containing different gelsemine concentrations. Effects on larval development time, prepupa cocoon mass, adult emergence, and adult mass were measured.
3. Nectar gelsemine had no effect on any measure of offspring performance. Thus, although gelsemine deters foraging by adult bees, this behaviour did not optimize offspring performance under the experimental conditions of this study. In contrast, sugar added to nectar treatments increased offspring mass.
4. While adult pollinators may avoid nectar with secondary compounds, this could hinder offspring performance by reducing sugar in provisions if nectar is limiting in the environment. Preference-performance trade-offs, which are studied extensively with foliar herbivores, have seldom been tested for pollinating plant consumers. Future studies of nectar secondary compounds and insect pollinator preference and performance may help to integrate studies of foliage-consuming insect herbivores with nectar-consuming insect pollinators.     

Determinants of successful establishment and post‐translocation dispersal of a new population of the critically endangered St. Croix ground lizard (Ameiva polops)

Translocation to areas free of exotic predators, habitat degradation, or disease may be the most viable restoration option for many endangered species. We report on a successful translocation of the critically endangered St. Croix ground lizard, Ameiva polops, extirpated from St. Croix, U.S. Virgin Islands, Caribbean, by predation from introduced mongooses (Herpestes auropunctatus). We translocated 57 adult A. polops from Green Cay to Buck Island in May 2008. We placed 4 females and 3 males each in eight, 100 m², enclosures on Buck Island for 71 days, then the enclosures were opened. During the enclosure period, 20 individuals were identified and 32 others were seen. The average number sighted per survey was only 5.28 (range = 2–10). One hatchling was sighted in an enclosure, indicating a translocated female successfully nested. Body condition of the translocated individuals increased significantly by the end of the enclosure period. Population monitoring surveys at 61 sites across Buck Island showed that 5 years after the initial translocation in June 2013, the new population had grown to an estimated 1,473 individuals and occupied 58.9% of the island. We attribute eradication of mongoose, life history of the species, large propagule size, condition of habitat, soft‐release, use of adults, interagency collaboration, and systematic assessment as primary factors that facilitated this successful translocation. Our findings provide meaningful insights on factors that enhance the potential for successful translocations, and point to new strategies aimed at restoring populations of endangered reptiles in their native ranges.     

Biological studies of the flesh flySarcophaga (Parasarcophaga) misera and its effects as a predator of the snailIndoplanorbis exustus

Attempts were made to identify a natural predator of the freshwater snailIndoplanorbis exustus, vector of schistosomiasis. Ochterlony's double immunodiffusion technique was used. The flySarcophaga (Parasarcophaga) misera was identified as a predator ofI. exustus. Various aspects of the biology of this fly and its effects as a predator of snailI. exustus were studied in the laboratory. The possible use of the larvae of this fly to controlI. exustus is discussed as an additional control measure to chemical control.      

Genetic diversity does not affect the invasiveness of fountain grass (Pennisetum setaceum) in Arizona, California and Hawaii

Pennisetum setaceum (Poaceae) is a perennial bunch grass that invaded the United States during the 20th century and is highly invasive in Hawaii, moderately invasive in Arizona, and not yet invasive in southern California. Pennisetum setaceum is apomictic, a condition that is normally associated with low genetic variation within populations, but even moderate levels of genetic variation among populations could account for differences in invasiveness. To determine whether genetic factors are causing the variable invasion success, we used Inter‐Simple Sequence Repeat markers (ISSRs) to examine genetic variation in populations from the three areas. Screening of 16 primers revealed no genetic variation within any population or between any geographical areas, a pattern consistent with complete apomixis. Variation in invasion success appears unrelated to genetic differences among populations. Differences in the seasonal timing of rainfall among the regions may be the cause of variable invasiveness of fountain grass. Alternatively, differences in timing of introduction or duration of lag phase may have limited invasiveness in Arizona and southern California.     

Pre-mRNA processing enhancer (PPE) element increases the expression of an intronless thymidylate synthase gene but does not affect intron-dependent S phase regulation

The pre-mRNA processing enhancer (PPE) element is an RNA sequence element derived from the intronless HSV-TK gene. Insertion of the element into the highly intron-dependent human β-globin gene leads to efficient expression in the absence of splicing. We have analyzed the effect of the PPE element on the expression of mouse thymidylate synthase (TS) minigenes. We have previously shown that the expression of intronless TS minigenes is moderately (up to 20-fold) stimulated by the inclusion of introns. Furthermore, S phase-specific expression of TS minigenes in growth-stimulated cells depends on the presence of a spliceable intron as well as the TS promoter. The goal of our study was to determine if the PPE element would overcome the dependence on introns for efficient expression and for S phase-specific expression of transfected TS minigenes. We found that insertion of the PPE element into an intronless TS minigene partially overcame intron dependence. However, the increase in expression was much less than that observed for the intronless β-globin gene. We also found that intronless TS or HSV-TK genes that contained the PPE element and that were driven by the TS promoter were expressed at a constant level in serum-stimulated cells. However, when an intron was included in these genes, they were expressed in an S phase-specific manner. Thus the PPE element was not able to overcome the dependence on introns for S phase-specific expression of TS minigenes. J. Cell. Biochem. 69:104–116, 1998. © 1998 Wiley-Liss, Inc.