丝带凤蝶线粒体基因组全序列及其系统学意义(英文)

锯凤蝶类与凤蝶科其他类群的系统发生关系及其分类学地位一直存在争议。本研究采用PCR和long PCR技术测定了属于锯凤蝶类的丝带凤蝶Sericinus montelus线粒体基因组全序列; 结合已有的其他凤蝶科物种的相应序列数据, 基于13个蛋白质编码基因重建了凤蝶科主要类群的系统发生树, 探讨了它们之间的系统发生关系。基因组分析结果表明： 丝带凤蝶线粒体基因组全长15 242 bp, 包括13个编码蛋白基因(ATP6, ATP8, COⅠ-Ⅲ, ND1-6, ND4L和Cytb)、 22个tRNA基因、 16S和12S rRNA基因以及非编码的控制区; 基因组A, T, G和C含量分别为40.1%, 40.8%, 7.4%和11.7%, 表现出明显的AT偏倚。所有的蛋白质编码基因都使用标准的起始密码子(ATN); 除ND4 和 ND4L基因使用单个的T作为终止密码子外, 其余蛋白编码基因都使用了标准的终止密码子(TAA)。除丝氨酸 tRNA的二氢尿苷突环缺失外, 所有tRNA基因都形成典型的三叶草型结构。基因组中共存在12个大小介于2~65 bp之间的基因间隔区以及15个大小介于1~8 bp之间的基因重叠区, 其中, 存在于COⅡ和tRNA^Lys之间的24 bp的间隔区在其他鳞翅目昆虫中未曾见到。以邻接法和最大简约法并基于13个蛋白质编码基因序列对凤蝶科进行了系统发生分析。结果显示, 丝带凤蝶和中华虎凤蝶Luehdorfia chinensis先构成一个支系, 再和冰清绢蝶Parnassius bremeri构成姊妹群; 表明锯凤蝶类应作为族级分类单元归于凤蝶科下的绢蝶亚科。     

Pupal colour dimorphism in a desert swallowtail (Lepidoptera: Papilionidae) is driven by changes in food availability,not photoperiod

1. The swallowtail butterfly Battus polydamas archidamas Boisduval, 1936, exhibits polyphenism for pupal coloration (green and brown). It is distributed across arid regions with winter rains and is monophagous on Aristolochia plants, which emerge after the winter rains and dry out the during summer. Thus, day length does not covary positively with host plant productivity. It was hypothesised that pupal colour was driven by food availability, not photoperiod. The benefits of pupal coloration matching the colour of pupation sites in terms of field survival were also investigated to evaluate the adaptive value of pupa colour. 2. Larvae were reared under a factorial array of two photoperiods (LD 10:14 h and LD 14:10 h) and two food availability regimes (leaves ad libitum and available every other day) to assess the frequency of green and brown pupae. Field survival of green and brown pupae was quantified in three commonly used habitats that differ in background coloration (cacti, rocks and shrubs). 3. Food availability determined pupal colour. Larvae in the ad libitum regime resulted mostly in green pupae, while those with restricted food were mostly brown. In contrast, photoperiod did not influence pupal colour. Survival probability of pupae placed on cacti was higher than those placed on rocks and shrubs, and the lowest predation risk across habitats was for green pupae on cacti. 4. Food availability plays a major role in the seasonal polyphenism for pupal colour of specialist butterflies inhabiting arid environments with winter rains.     

Divergence in the ovipositional behavior of the Papilio glaucus group

This study contrasts the ovipositional profiles of four members of the Papilio glaucus group, P. glaucus , P. multicaudatus , P. canadensis , and P. rutulus. We used seven choice oviposition bioassays containing leaves from hosts in seven plant families utilized by members of the P. glaucus group. Specifically, we contrast the overall ovipositional profiles of these species and their acceptance of a host in a novel plant family ( Populus tremuloides : Salicaceae) and a host in a putatively ancestral host plant family ( Liriodendron tulipifera : Magnoliaceae). Significant differences were observed between the ovipositional profiles of P. glaucus and P. multicaudatus relative to each other and to P. canadensis and P. rutulus. In contrast, no significant differences were observed between the ovipositional profiles of P. canadensis and P. rutulus , which were also the only species that accepted P. tremuloides. Unlike the acceptance of P. tremuloides , the acceptance of L. tulipifera was present throughout the group despite the inability of the larvae of most species in the group to utilize this host. These results support the prediction of the "hierarchical threshold model" that ancestral host plants are likely to be retained in the ovipositional hierarchy while novel hosts should only be accepted by derived populations.     

Diversification of host use in two polyphagous butterflies: differences in oviposition specificity or host rank hierarchy?

Novel host usage may represent an initial step towards diversification or radiation onto novel hosts within an evolutionary lineage, particularly if a shift in host plant preference ranking takes place. Polyphagous stages of evolutionary lineages may represent transitional states in which novel host associations are more likely to develop, but may be more difficult to detect experimentally. The polyphagous sister species Papilio glaucus L. and Papilio canadensis (Lepidoptera: Papilionidae; these Papilio = Pterourus) are known to exhibit differences in host‐plant use, despite significant overlap in host‐use abilities, providing an opportunity to examine how host shifts in polyphagous species may occur and what the implications for future divergence may be. In particular, we were interested in (i) determining whether differences in oviposition behavior of these species were due to changes in specificity or shifts in host‐plant hierarchy, (ii) whether the varying preference for primary hosts also affected the preference for secondary hosts, and (iii) what the oviposition preferences of a new hybrid swarm population are. We examined more than 40 000 oviposition bouts from more than 400 P. glaucus, P. canadensis, and hybrid females placed in seven‐, three‐, or two‐choice assays. In each of the choice assays, leaves from plants in different plant families of varying suitability for P. glaucus and P. canadensis larvae were used. We found the primary difference between P. glaucus and P. canadensis to be limited to a Z‐linked shift in host rank hierarchy due to an acceptance of Populus tremuloides Michx. (Salicaceae) and reduced specificity for Liriodendron tulipifera L. (Magnoliaceae) in P. canadensis. In addition, we found the absence of the Z‐linked oviposition acceptance of P. tremuloides in a recently formed allochronically separated hybrid swarm population found in P. canadensis territory at the northern border of the P. glaucus and P. canadensis hybrid zone.     

Patterns of Amazonian area relationships based on raw distributions of papilionid butterflies (Lepidoptera: Papilioninae)

Diversifications within a biota are due to several factors. Although some of these are untestable with current analytical methods, hierarchical congruence obtained with different cladistic methods and based on independent taxa are undoubtedly important. In the recent past, most hypotheses of historical biogeography (e.g. refugial, riverine, disturbance, vicariance) were tested on the Amazonian biota, selecting a number of diverse organisms such as plants, anurans, lizards, butterflies, birds and monkeys. In this study we used parsimony analysis of endemicity to infer historical relationships among 16 interfluvial areas in the Amazonian lowlands based on raw distributions of 114 Papilioninae (Lepidoptera). The analysis yielded two most parsimonious trees of area relationships. One tree was characterized by two main clusters of areas which showed a separation of Guyanan + south-east Amazonian interfluvial areas from western Amazonian interfluvial areas. The second tree showed the Guyanan interfluvial areas basal to a cluster which included all the other interfluvial areas. This latter cluster was subdivided into two main groups of areas separating the south-east Amazonian and the western Amazonian interfluvial areas. This result is discussed in the light of previous hypotheses obtained with the same method using some vertebrate taxa in the Amazonian lowlands. Likewise, comparisons with other hypotheses on lineages of birds, mammals and butterflies obtained applying cladistic biogeographical methods are made. The two alternative vicariant patterns presented for papilionid butterflies are strictly congruent with those for birds.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 345–357.     

Diapause pupal color diphenism induced by temperature and humidity conditions in Byasa alcinous (Lepidoptera: Papilionidae)

We investigated whether diapause pupae of Byasa alcinous exhibit pupal color diphenism (or polyphenism) similar to the diapause pupal color polyphenism shown by Papilio xuthus. All diapause pupae of B. alcinous observed in the field during winter showed pupal coloration of a dark-brown type. When larvae were reared and allowed to reach pupation under short-day conditions at 18 °C under a 60 ± 5% relative humidity, diapause pupae exhibited pupal color types of brown (33%), light-brown (25%), yellowish-brown (21%), diapause light-yellow (14%) and diapause yellow (7%). When mature larvae reared at 18 °C were transferred and allowed to reach pupation at 10 °C and 25 °C under a 60 ± 5% relative humidity after a gut purge, the developmental ratio of brown and light-brown, yellowish-brown, and diapause light-yellow and diapause yellow types was 91.2, 8.8 and 0.0% at 10 °C, and 12.2, 48.8 and 39.0% at 25 °C, respectively. On the other hand, when mature larvae reared at 18 °C were transferred and allowed to reach pupation at 10 °C, 18 °C and 25 °C under an over 90% relative humidity after a gut purge, the developmental ratio of brown and light-brown, yellowish-brown, and diapause light-yellow and diapause yellow types was 79.8, 16.9 and 3.3% at 10 °C, 14.5, 26.9 and 58.6% at 18 °C, and 8.3, 21.2 and 70.5% at 25 °C, respectively. These results indicate that diapause pupae of brown types are induced by lower temperature and humidity conditions, whereas yellow types are induced by higher temperature and humidity conditions. The findings of this study show that diapause pupae of B. alcinous exhibit pupal color diphenism comprising brown and diapause yellow types, and suggest that temperature and humidity experienced after a gut purge are the main factors that affect the diapause pupal coloration of B. alcinous as environmental cues.     

Beak marks on the wings of butterflies and predation pressure in the field

Beak marks on butterfly wings have been used as an indicator of predation pressure. The relationship between butterflies and their predators in the field was examined to evaluate the beak mark rate as an indicator of predation pressure. Transect censuses were conducted to measure the beak mark rate on butterflies from May to November, 2010, in Shiga Prefecture, Japan. A total of 1216 butterflies of 42 species from five families were observed during the study period. The beak mark rate in the Papilionidae was significantly higher than those of all other families. Analysis of the monthly fluctuations in the beak mark rate and relative abundance of predators revealed that the higher beak mark rates observed for two butterfly families (Papilionidae and Nymphalidae) were significantly and positively related to predation pressure, while no significant relationship was found for other families (Lycaenidae, Pieridae and Hesperiidae). Beak marks in larger butterflies (Papilionidae and Nymphalidae) can be used as an indicator to evaluate the relative intensity of predation pressure in the field.     

Survivorship and growth in the larvae of Luehdorfia japonica feeding on old leaves of Asarum megacalyx

Although the papilionid butterfly Luehdorfia japonica, usually lays eggs on new leaves of the host plant (Asarum sp.; Aristolochiaceae), eggs of the butterfly were frequently found on old leaves of Asarum megacalyx in Suyama, Tokamachi, Niigata prefecture. Larvae hatched on new leaves and those hatched on old leaves did not show significant differences in their survival rate in the field. In laboratory breeding, about 90% of larvae that were fed old leaves survived and developed normally to the pupal stage. Their growth rate, however, was slightly lower than those that were fed new leaves. No nutritional differences were found between the old and new leaves. The reason why oviposition on the old leaves was so frequent and why larvae that hatched on old leaves could survive in the study area is discussed.     

Taste sensitivity and divergence in host plant acceptance between adult females and larvae of Papilio hospiton

On the island of Sardinia the lepidopteran Papilio hospiton uses Ferula communis as exclusive host plant. However, on the small island of Tavolara, adult females lay eggs on Seseli tortuosum, a plant confined to the island. When raised in captivity on Seseli only few larvae grew beyond the first–second instar. Host specificity of lepidopterans is determined by female oviposition preferences, but also by larval food acceptance, and adult and larval taste sensitivity may be related to host selection in both cases. Aim of this work was: (i) to study the taste sensitivity of larvae and ovipositing females to saps of Ferula and Seseli; (ii) to cross‐compare the spike activity of gustatory receptor neurons (GRNs) to both taste stimuli; (iii) to evaluate the discriminating capability between the two saps and determine which neural code/s is/are used. The results show that: (i) the spike responses of the tarsal GRNs of adult females to both plant saps are not different and therefore they cannot discriminate the two plants; (ii) larval L‐lat GRN shows a higher activity in response to Seseli than Ferula, while the opposite occurs for the phagostimulant neurons, and larvae may discriminate between the two saps by means of multiple neural codes; (iii) the number of eggs laid on the two plants is the same, but the larval growth performance is better on Ferula than Seseli. Taste sensitivity differences may explain the absence of a positive relationship between oviposition preferences by adult females and plant acceptance and growth performance by larvae.     

Taste input from tarsal sensilla is related to egg‐laying behavior in Papilio hospiton

In herbivorous insects, host selection involves various sensory modalities (sight, smell, taste), but the contact chemoreceptors capable of detecting stimuli both from host and non‐host plants play an important role in the final steps of oviposition behavior. Female butterflies scratch and drum the leaf surface and taste the compounds present in plant saps with their tarsal chemosensilla. We assumed that tarsal taste sensitivity may be related to the breadth of host selection in ovipositing females of Papilio hospitonGéné (Lepidoptera: Papilionidae). The spike activity of tarsal taste basiconic sensilla was recorded in response to stimulation with NaCl, bitter compounds, and carbohydrates, with the aim of characterizing the gustatory receptor neurons (GRNs) and of comparing the response patterns in the light of differences in acceptability of host plants. Then we studied the sensitivity of GRNs to saps of the host plants Ferula communis L., Peucedanum paniculatumLoisel, Pastinaca latifolia (Duby) DC. (all Apiaceae), and Ruta lamarmorae Bacch., Brullo et Giusso (Rutaceae), and evaluated the relationship between taste sensitivity and oviposition preference. The results indicate that (1) each sensillum houses sugar‐, bitter‐, and salt‐sensitive cells; (2) the spike activity of the gustatory neurons in response to plant saps produces a different response pattern across all active GRNs; and (3) the number of eggs laid on each plant is highest on F. communis and lowest on R. lamarmorae. These results suggest that the varying activity of the tarsal GRNs may affect host plant acceptability and that ovipositing females of P. hospiton seem to be able to discriminate between host plants.