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1.
A hard tick larva in Cretaceous Burmese amber is described as Cornupalpatum burmanicum n. g., n. sp. Diagnostic characters include a subcircular body with a marginal groove, 11 festoons, elongate four-segmented palpi with the fourth segment distinct and apical, the absence of an anal groove and eyes, and the presence of claws on palpal segment 3. The last character is unique for all members of the Ixodida, both fossil and extant. Aside from the palpal claws and marginal groove, features of the tick larva closely resemble those of members of the genus Aponomma Neumann 1899, considered one of the most primitive tick lineages today, whose hosts are primarily reptiles.  相似文献   

2.
The tick Hyalomma (Euhyalomma) asiaticum Schulze & Schlottke is provisionally considered to belong to the H. (E.) asiaticum group of closely related species. Males of H. asiaticum can be distinguished from those of other species of the group by their long and very deep cervical grooves, long, narrow, straight adanal plates, long dorsal prolongation of the spiracular plates, dorsal posterior margin of the basis capituli deeply concave and angular, and unbroken ivory-coloured strip on the dorsal aspect of the leg segments. Females of H. asiaticum can be distinguished from those of other species of the H. asiaticum group by their very deep cervical grooves, narrowly U-shaped genital aperture, with bulging preatrial fold. Larger domestic and wild ungulates are the principal hosts of the adults, while nymphs and larvae parasitize mainly rodents, leporids and hedgehogs. Hyalomma asiaticum is widely distributed in Asia, from Syria in the West to eastern China in the East. Here all the parasitic stages of H. asiaticum are illustrated and redescribed. Data on its disease relationships are also provided.  相似文献   

3.
Amblyomma integrum Karsch, 1879 (Acari: Ixodidae) is one of four Amblyomma Koch, 1844 species with eyes found in southern India and Sri Lanka. The immature stages of this species were poorly described. Therefore, accurate identification is difficult. Here we re‐describe the male, female, nymph and larva of A. integrum and illustrate all the stages in greater detail for the first time. A set of diagnostic morphological characters is defined to distinguish this species from other sympatric species of eyed Amblyomma in any parasitic stage of development. Adults of A. integrum parasitize mostly various larger mammals whereas nymphs and larvae use mostly larger and medium mammals. Amblyomma integrum is recorded from India (Andhra Pradesh, Goa, Karnataka, Orissa and Tamil Nadu States) and throughout Sri Lanka.  相似文献   

4.
The complete larval development (four zoeae and one megalopa) of Clibanarius aequabilis and C. erythropus, reared under laboratory conditions, is described and illustrated. The larval stages of the two northeastern Atlantic Clibanarius species cannot be easily differentiated. Their morphological characters are compared with those of other known Clibanarius larvae. The genus Clibanarius is very homogeneous with respect to larval characters. All Clibanarius zoeae display a broad and blunt rostrum, smooth abdominal segments and an antennal scale without a terminal spine. Beyond the second zoeal stage, the fourth telson process is present as a fused spine, and the uropods are biramous. In the fourth larval stage all species display a mandibular palp. The Clibanarius megalopa presents weakly developed or no ocular scales, symmetrical chelipeds, apically curved corneous dactylus in the second and third pereiopods, and 5–11 setae on the posterior margin of the telson. Apart from the number of zoeal stages, Clibanarius species may be separated, beyond the second zoeal stage, by the telson formula and the morphology of the fourth telson process.  相似文献   

5.
曾蕾  闫瑞亚  张梅  许为斌  张林静  于胜祥 《广西植物》2016,36(10):1245-1252
棒凤仙亚属代表着凤仙花属最先分化出的一支,以多年生草本,多于5朵花的总状花序,侧生萼片4枚,3沟花粉,心皮四室且每室具1枚种子,果实棒锤状,种子椭圆形以及三沟花粉其极面观为三角形而区别于其它种类。该亚属主要分布于中国南部,少数种类辐射分布至华中和中南半岛地区。已有报道证实花粉的形态特征对凤仙花属植物的属下分类具有重要意义,但对棒凤仙亚属的种类少有涉及。为了进一步探讨该亚属花粉的形态特征及其分类学价值,该研究应用扫描电镜技术对国产棒凤仙亚属植物的14种以及凤仙花亚属的窄萼凤仙花的花粉进行了观察。结果表明:棒凤仙亚属的花粉以单粒存在,具3条萌发沟,辐射对称,极面观为三角形或三角状圆形,花粉粒外壁具均匀的网状纹饰,网脊平滑或具波状边缘,网眼中具不同密度的颗粒状突起。棒凤仙亚属的花粉形态与水角属的花粉形态相似,表现出了其原始性;其花粉形态特征与花部形态性状等相关性差,对该亚属的组级分类意义较小,但对于该亚属的种间界定具有重要意义;而其花粉的极面观形状、赤道面观形状以及网状纹饰等变异相对稳定,对于界定该亚属具有重要的分类学价值。  相似文献   

6.
The larval stage of Tortopus is redescribed based on three species: T. puella from North America, the only species of the genus previously known from larva, and the larvae of T. obscuripennis and T. sarae from South America described here. Generic characters of the larva include: relatively large finger-like gill near base of maxilla, inner margin of mandibular tusks with a subdistal tubercle, straight or weakly convex frontal ridge present between antennae, reduced unilamellated gill on abdominal segment I. Additionally the male imagines of both Neotropical species are described for the first time, and T. obscuripennis is recorded from Bolivia. Diagnoses, SEM photographs, and illustrations are given for the new stages described and for the identification of the three Tortopus species known as larvae.  相似文献   

7.
Herein, we provide external and internal morphological data of Scinax skuki tadpoles from its type locality. The benthic tadpole of S. skuki has eyes and nostrils positioned dorsally, vent tube dextral and reaching the free margin of the ventral fin, oral disk ventral with posterior margin concave when partially closed, labial tooth row formula 2/3, and the presence of nonpigmented spurs behind the lower jaw. These characters, together with the absence of a tectum parietale, and the shapes of the pars articularis quadrati and suprarostral, are useful for species identification and may be informative for systematic purposes.  相似文献   

8.
Lu Jiang  Chao Yue  Baozhen Hua 《ZooKeys》2014,(398):69-82
Larval characters play a significant role in evolutionary and systematic studies of holometabolous insects. However, Panorpodidae, a derived family of Mecoptera, are largely unknown in their immature stages to date. Here, the first instar larva of the short-faced scorpionfly Panorpodes kuandianensis Zhong, Zhang & Hua, 2011 is described and illustrated using light and scanning electron microscopy. The larva of Panorpodes is remarkable for the absence of compound eyes on the head and the presence of seven small unpaired proleg-like processes along the midventral line on abdominal segments II–VIII. The homology of these unpaired appendage-like processes, their ecological adaptation, and the evolutionary implications of some larval characters of Panorpodidae are discussed.  相似文献   

9.
记述了郑氏红蚁Myrmica zhengi Ma & Xu雌性生殖蚁新发现。该蚁与工蚁相似,但头部具3枚单眼;复眼大,具深色斑块。唇基圆凸成球状,端缘平直。中胸背板发达,遮盖前胸背板,背侧平坦,后胸背板明显;并胸腹节刺粗大,基部宽,约为并胸腹节基面长的一半。上颚具有光泽;并腹胸具纵形刻纹;腹柄,后腹柄背面和腹部光亮。体棕色,中胸背板边缘具直立毛,后腹柄后部具1列横直立毛。其余刻纹被毛的分布情况似工蚁。标本存放于陕西师范大学动物研究所。  相似文献   

10.
Larval morphology can provide valuable characters for taxonomic and phylogenetic analyses of insects and reflect the adaptations to various living habits. Compared with the adult stages, larval study has lagged far behind in Mecoptera. Although several genera of Panorpidae have been studied for their larval stages, the larva of Dicerapanorpa Zhong and Hua, 2013 basically remains unclear. Here the larva of Dicerapanorpa magna (Chou) is described and illustrated in detail for the first time using light microscopy and scanning electron microscopy. The larva is eruciform, with eight pairs of abdominal prolegs in addition to three pairs of thoracic legs, as in other Panorpidae. The most remarkable characteristics of the larvae include a pair of erect subdorsal annulated processes each on abdominal segments I–IX (A1–A9) and a single middorsal annulated process on A10, as well as a pair of prominent compound eyes composed of over 40 ommatidia, which distinguish this genus from other genera of Panorpidae. The annulated processes may have adaptive significance for fossorial and soil-living habits.  相似文献   

11.
A new Heterorhabditis species was isolated from nymphal stages of the seasonal cicada Diceroprocta ornea (Walker) in an asparagus field in the state of Sonora, Mexico. Concomitantly, another isolate of the same nematode species was also collected from an oak woodland habitat in the Chiricahua mountain range in southeastern Arizona. Morphological and molecular studies together with cross-hybridization tests indicate these two isolates are conspecific and represent a new undescribed Heterorhabditis sp. This new species is distinguished from other species in this genus by a combination of several qualitative and quantitative morphological traits. Key diagnostic features include: presence of a pronounced post-anal swelling in the hermaphrodite; male with nine pairs of bursal rays, with pairs 4 and 7 bent outwards and one pair of papillae placed on the cloacal opening, value of D% (average: 79); infective juveniles with a well developed cuticular tooth, long tail (average: 105 μm) and values of D% (average: 90) and E% (average: 99). In addition to these diagnostic characters, cross-hybridization tests between the new species with H. bacteriophora and H. mexicana yielded no fertile progeny. Comparison of ITS rDNA sequences with other available sequences of described species depicted the two isolates as a new species. Phylogenetic analysis of these sequence data placed H. sonorensis n. sp. as a member of the indica-group.  相似文献   

12.
王永  何顺志 《广西植物》2015,35(4):476-486
采用制作叶脉标本和透明叶标本的方法,对贵州产28种2变种小檗属植物叶脉特征进行比较研究。结果表明:贵州小檗属植物的脉序类型有5种:半达缘羽状脉、花环状半达缘羽状脉、简单弓形羽状脉、花环状弓形羽状脉和混合型。叶脉分支一般有五级:1一级脉构架均为羽状脉,粗度有很粗、粗、中等粗细和纤细四种类型,分支方式包括单轴分支和合轴分支;2粗二级脉构架中有分支达缘或分支均不达缘,与中脉夹角变化各异,内二级脉存在或缺失,细二级脉半达缘、真曲行或简单弓形,间二级脉类型复杂多变但频度种间有差异;3三级脉贯串型、结网型或分支型;4四、五级脉网状或自由分支且常混合在一起。脉间区从发育差到良好,小脉从不分支到不均等分支等各种类型均有,叶缘末级脉缺失、不完整、钉状和环状。大部分种类叶缘具齿,每1cm齿数目和齿内腺点的特性等特征在不同种类间有区别,具有鉴定价值,但齿其它特征复杂多变或种间区别较小,同时齿内脉性状也不稳定。此外,齿的有无会对脉序类型产生影响。小檗属植物叶脉类型存在种间差异,具有重要的分类学价值,叶脉类型的变化和复杂程度显示了该属植物的进化特点;叶齿的有无和齿特征具有分类学和系统学意义。基于叶脉特征的研究结果并结合重要的外部形态学特征编制了贵州小檗属植物的分种检索表。研究结果可为小檗属植物分类寻找新的依据并探讨其系统学意义。  相似文献   

13.
14.
Fourth-stage larvae of four species of the Cyathostominae Nicoll, 1927 parasitic in donkeys Equus asinus L. from Ethiopia were identified mainly using moulting specimens. They are Cylicocyclus asini Matthee, Krecek & Gibbons, 2001, C. auriculatus (Looss, 1900) Chaves, 1930, Cyathostomum tetracanthum (Mehlis, 1831) Molin, 1861 (sensu Looss, 1900) and Cylindropharynx brevicauda Leiper, 1911. The larva of Cylicocyclus asini is similar to those of C. nassatus (Looss, 1900) Chaves, 1930 and C. leptostomum Kotlán, 1920, but differs from the former by the shape of the dorsal tooth in the oesophageal funnel, which is notably smaller than in C. asini but similar to that of C. leptostomum. However, the larva of C. asini differs from that of C. leptostomum in the size of the buccal capsule, which is notably larger than in C. leptostomum but similar to that of C. nassatus. The larva of C. auriculatus is very similar to that of C. insigne (Boulenger, 1917) Chaves, 1930. The larva of Cyathostomum tetracanthum is similar to those of Cylicostephanus bidentatus (Ihle, 1925) Lichtenfels, 1975, C. goldi (Boulenger, 1917) Lichtenfels, 1975 and Cyathostomum catinatum Looss, 1900. The larva of Cylindropharynx brevicauda is similar to that of Petrovinema skrjabini (Ershov, 1930) Ershov, 1943 but smaller in size. Including the four cyathostomine species identified in the present study, 36 species belonging to 13 genera have so far been described and identified of a total of 64 recognised and confirmed species of equine strongyles.  相似文献   

15.
The cranial morphology of the extinct murid genus Stephanomys, previously known only by dental remains, is described here on the basis of partial skulls of three species of Pliocene age. Important cranial characters of the genus are a robust rostrum, a high zygoma, a wide zygomatic arch, a narrow interorbit, a large orbit, and an optic foramen in the backward position. In addition to some dental characters, Stephanomys shares most of these cranial traits with the extinct Malpaisomys from the Canary Islands. Some of these traits may be linked to the development of large eyes and life in a rocky environment. The peculiar dental pattern of Stephanomys (stephanodonty) is also present in some recent murids (Oenomys and Thamnomys) having a different skull morphology. A comparison with nine other extant genera of murids verified the relationship among Malpaisomys, Stephanomys, and Acomys, supporting our previous conclusion. Phenetic and cladistic analyses of 17 cranial and 23 dental characters show that skull morphology is phylogenetically informative but highly convergent and incongruent with other partial evidence based on dental and biochemical characters. The combined analyses of skull and teeth illustrate a case of mosaic evolution in murids.  相似文献   

16.
The preimaginal stages including egg, mature larva and pupa of Pseudaspidapion botanicum Alonso-Zarazaga & Wang, 2011 were described and figured, diagnostic characters of larva and pupa were discussed, and corresponding biological information was supplied. The nomenclature of frontal setae in the larva compared with curculionid weevils, the absence of the hypopharyngeal bracon in the larva, and the metafemoral setae in the pupa were discussed. Common and different characters among the larvae of Pseudaspidapion botanicum, Aspidapion radiolus (Marsham, 1802) and Aspidapion aeneum (Fabricius, 1775) were also provided.  相似文献   

17.
橘绵粉虱是一种危险性的入侵生物,已于2018年11月在我国海南文昌的番石榴上发现。本文记述了橘绵粉虱各虫态的形态特征、野外鉴别特征,并列出了其分布及重要寄主植物,附有彩色生态照片。由于橘绵粉虱是柑橘类的重要害虫,具有向中国大陆扩散的可能性,我国南方柑橘产区应密切关注此虫动态。  相似文献   

18.
While most malacostracan crustaceans develop through superficial cleavage, in the Amphipoda, Euphausiacea, and Dendrobranchiata (Decapoda) cleavage is complete. Euphausiaceans and dendrobranchiate shrimp share a similar early cleavage pattern, early cleavage arrest and ingression of mesendoderm progenitor cells, a ring of crown cells (prospective naupliar mesoderm) around the blastopore, and hatching as a nauplius larva. Yet recent phylogenies do not support a close relationship between Euphausiacea and Decapoda. In addition, some variation is reported in the timing of mesendoderm cell arrest and number of crown cells for a number of dendrobranchiates. To determine the representative pattern of development in the Dendrobranchiata, embryos of the Pacific white shrimp Penaeus (Litopenaeus) vannamei were stained with Sytox Green to label chromosomes and nuclei and examined with confocal microscopy. The early cleavage pattern, mesendoblast arrest and subsequent ingression at the 32-cell stage, presence of 8 initial crown cells, and fates of the mesendoblasts are the same for P. vannamei (family Peneaeidae) and Sicyonia ingentis (family Sicyoniidae). The lineage of the primordial endoderm cells differs from that reported for P. kerathurus. These characters were discussed in the context of the evolution of development in the Dendrobranchiata and in comparison to the Euphausiacea.  相似文献   

19.
In the present paper, based on material from Brazil, we present a contribution to the taxonomy of the Neotropical two-winged Leptophlebiidae. The male imago of Perissophlebiodes Savage is described, in addition to a new species of Askola Peters from Amazonas. Askola emmerichi Domínguez, Molineri and Mariano, so far recorded from Venezuela, is reported from Brazil and compared to the new species herein described. Askola yanoman, sp. nov. can be separated from other species of the genus by the following combination of characters: (1) general colouration yellowish brown with areas washed with greyish brown; (2) dorsal portion of eyes brown, eyes meet on meson of head; (3) penis yellowish brown with darker margin, extending beyond the posterior margin of the styliger plate.  相似文献   

20.
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