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Chuandianella
''Chuandianella ovata'' is an extinct bivalved arthropod that lived during Cambrian Stage 3 of the Early Cambrian (about 520 to 516 million years ago). It is the only species classified under the genus ''Chuandianella''. Its fossils were recovered from the Chengjiang Biota in Yunnan, China. Taxonomy It was originally described in 1975 under the "ostracod"-like genus '' Mononotella'', as ''Mononotella ovata''. In 1991, the paleontologists Xian-Guang Hou and Jan Bergström reclassified it under the new genus ''Chuandianella'' when additional discoveries of more complete specimens made its resemblance to ''Waptia fieldensis'' more apparent. In 2004, paleontologist Jun-Yuan Chen tentatively transferred it to the genus ''Waptia''. However, ''C. ovata'' had eight abdominal somites in contrast to five in ''W. fieldensis''. Its limbs were biramous and were undifferentiated, unlike those of ''W. fieldensis''. Other authors deemed these differences to be enough to separate it from ''Wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chuandianella Diagrammatic Reconstruction
''Chuandianella ovata'' is an extinct bivalved arthropod that lived during Cambrian Stage 3 of the Early Cambrian (about 520 to 516 million years ago). It is the only species classified under the genus ''Chuandianella''. Its fossils were recovered from the Chengjiang Biota in Yunnan, China. Taxonomy It was originally described in 1975 under the "ostracod"-like genus '' Mononotella'', as ''Mononotella ovata''. In 1991, the paleontologists Xian-Guang Hou and Jan Bergström reclassified it under the new genus ''Chuandianella'' when additional discoveries of more complete specimens made its resemblance to ''Waptia fieldensis'' more apparent. In 2004, paleontologist Jun-Yuan Chen tentatively transferred it to the genus ''Waptia''. However, ''C. ovata'' had eight abdominal somites in contrast to five in ''W. fieldensis''. Its limbs were biramous and were undifferentiated, unlike those of ''W. fieldensis''. Other authors deemed these differences to be enough to separate it from ''Wap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waptia Fieldensis
''Waptia fieldensis'' is an extinct species of arthropod from the Middle Cambrian Burgess Shale ''Lagerstätte'' of Canada. It grew to a length of , and had a large bivalved carapace and a segmented body terminating into a pair of tail flaps. It was an active swimmer and likely a predator of soft-bodied prey. It is also one of the oldest animals with direct evidence of brood care. ''Waptia fieldensis'' is the only species classified under the genus ''Waptia''. Other specimens of ''Waptia'' are known from the Spence Shale in Utah. Based on the number of individuals, ''Waptia fieldensis'' is the third most abundant arthropod from the Burgess Shale Formation, with thousands of specimens collected. It was among the first fossils found by the American paleontologist Charles D. Walcott in 1909. He described it in 1912 and named it after two mountains near the discovery site – Wapta Mountain and Mount Field, other specimens Although it bears a remarkable resemblance to modern crustac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waptia
''Waptia fieldensis'' is an extinct species of arthropod from the Middle Cambrian Burgess Shale ''Lagerstätte'' of Canada. It grew to a length of , and had a large bivalved carapace and a segmented body terminating into a pair of tail flaps. It was an active swimmer and likely a predator of soft-bodied prey. It is also one of the oldest animals with direct evidence of brood care. ''Waptia fieldensis'' is the only species classified under the genus ''Waptia''. Other specimens of ''Waptia'' are known from the Spence Shale in Utah. Based on the number of individuals, ''Waptia fieldensis'' is the third most abundant arthropod from the Burgess Shale Formation, with thousands of specimens collected. It was among the first fossils found by the American paleontologist Charles D. Walcott in 1909. He described it in 1912 and named it after two mountains near the discovery site – Wapta Mountain and Mount Field, other specimens Although it bears a remarkable resemblance to modern cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Chengjiang Biota Species By Phylum
This is a list of fossils found at Maotianshan Shales, whose most famous assemblage of organisms are referred to as the Chengjiang biota. Phylum Arthropod, Arthropoda 80 species, not counting Dinocarida, Nektaspida and Trilobita * ''Acanthomeridion, Acanthomeridion serratum'' * ''Alalcomenaeus'' * ''Almenia, Almenia spinosa'' * ''Apiocephalus, Apiocephalus elegans'' * ''Branchiocaris, Branchiocaris yunnanensis'' * ''Canadaspis, Canadaspis laevigata'' * ''Chengjiangocaris, Chengjiangocaris longiformis'' * ''Chuandianella, Chuandianella ovata'' * ''Cindarella, Cindarella eucalla'' * ''Clypecaris, Clypecaris pteroidea'' * ''Combinivalvula, Combinivalvula chengjiangensis'' * ''Comptaluta inflata'' * ''Comptaluta leshanensis'' * ''Cyathocepalus, Cyathocepalus bispinosus'' * ''Dianchia, Dianchia mirabilis'' * ''Diplopyge'' ** ''D. forcipatus'' ** ''D. minutus'' * ''Dongshanocaris, Dongshanocaris foliiformis'' * ''Ercaia, Ercaia minuscula'' * ''Ercaicunia, Ercaicunia multinodos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hymenocarina
Hymenocarina is an order of extinct arthropods known from the Cambrian. They possess bivalved carapaces, typically with exposed posteriors. Members of the group are morphologically diverse and had a variety of ecologies, including as filter feeders and as predators. Recent research has generally considered them to be stem or crown group members of Mandibulata, due the presence of mandibles in at least some species. Taxonomy Hymenocarines are characterized by the combination of following characters: bivalved, convex carapace covering cephalothoracic region; cephalothorax bearing multisegmented antennules and rounded mandibles, alongside post-maxillular limbs with spiny, subdivided basis and endopods with well-developed terminal claws; absence of appendages between antennules and mandibles; median sclerite and lobate protrusions located between compound eyes; posterior tagma (abdomen) with ring-like segments and terminated by a pair of well-developed caudal rami. Based on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian Stage 3
Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambrian Stage 2 and precedes Cambrian Stage 4, although neither its base nor top have been formally defined. The plan is for its lower boundary to correspond approximately to the first appearance of trilobites, about million years ago, though the globally asynchronous appearance of trilobites warrants the use of a separate, globally synchronous marker to define the base. The upper boundary and beginning of Cambrian Stage 4 is informally defined as the first appearance of the trilobite genera ''Olenellus'' or '' Redlichia'' around million years ago. Naming The International Commission on Stratigraphy has not officially named the 3rd stage of the Cambrian. The stage approximately corresponds to the "Atdabanian", which is used by geologists working in Siberia. Biostratigraphy The oldest trilobite known is ''Lemdadella'' which appears at the beginning of the '' Fallotaspis'' zone. The Cambrian radiati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna (biology)
Antennae ( antenna), sometimes referred to as "feelers", are paired appendages used for sensing in arthropods. Antennae are connected to the first one or two segments of the arthropod head. They vary widely in form but are always made of one or more jointed segments. While they are typically sensory organs, the exact nature of what they sense and how they sense it is not the same in all groups. Functions may variously include sensing touch, air motion, heat, vibration (sound), and especially smell or taste. Antennae are sometimes modified for other purposes, such as mating, brooding, swimming, and even anchoring the arthropod to a substrate. Larval arthropods have antennae that differ from those of the adult. Many crustaceans, for example, have free-swimming larvae that use their antennae for swimming. Antennae can also locate other group members if the insect lives in a group, like the ant. The common ancestor of all arthropods likely had one pair of uniramous (unbranched ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podomere
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, plural ''coxae''), ''trochanter'', ''femur'' (plural ''femora''), ''tibia'' (plural ''tibiae''), ''tarsus'' (plural ''tarsi''), ''ischium'' (plural ''ischia''), ''metatarsus'', ''carpus'', ''dactylus'' (meaning finger), ''patella'' (plural ''patellae''). Homologies of leg segments between groups are difficult to prove and are the source of much argument. Some authors posit up to eleven segments per leg for the most recent common ancestor of extant arthropods but modern arthropods have eight or fewer. It has been argued that the ancestral leg need not have been so complex, and that other events, such as successive loss of function of a ''Hox''-gene, could result in parallel gains of leg segments. In arthropods, each of the leg segments ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seta
In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. They help, for example, earthworms to attach to the surface and prevent backsliding during peristaltic motion. These hairs make it difficult to pull a worm straight from the ground. Setae in oligochaetes (a group including earthworms) are largely composed of chitin. They are classified according to the limb to which they are attached; for instance, notosetae are attached to notopodia; neurosetae to neuropodia. Crustaceans have mechano- and chemosensory setae. Setae are especially present on the mouthparts of crustaceans and can also be found on grooming limbs. In some cases, setae are modified into scale like structures. Setae on the legs of krill and other small crustaceans help them to gather phytoplankton. It captures them and allows th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biramous
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, plural ''coxae''), ''trochanter'', ''femur'' (plural ''femora''), ''tibia'' (plural ''tibiae''), ''tarsus'' (plural ''tarsi''), ''ischium'' (plural ''ischia''), ''metatarsus'', ''carpus'', ''dactylus'' (meaning finger), ''patella'' (plural ''patellae''). Homologies of leg segments between groups are difficult to prove and are the source of much argument. Some authors posit up to eleven segments per leg for the most recent common ancestor of extant arthropods but modern arthropods have eight or fewer. It has been argued that the ancestral leg need not have been so complex, and that other events, such as successive loss of function of a ''Hox''-gene, could result in parallel gains of leg segments. In arthropods, each of the leg segments artic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uniramous
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, plural ''coxae''), ''trochanter'', ''femur'' (plural ''femora''), ''tibia'' (plural ''tibiae''), ''tarsus'' (plural ''tarsi''), ''ischium'' (plural ''ischia''), ''metatarsus'', ''carpus'', ''dactylus'' (meaning finger), ''patella'' (plural ''patellae''). Homologies of leg segments between groups are difficult to prove and are the source of much argument. Some authors posit up to eleven segments per leg for the most recent common ancestor of extant arthropods but modern arthropods have eight or fewer. It has been argued that the ancestral leg need not have been so complex, and that other events, such as successive loss of function of a ''Hox''-gene, could result in parallel gains of leg segments. In arthropods, each of the leg segments artic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endopod
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, plural ''coxae''), ''trochanter'', ''femur'' (plural ''femora''), ''tibia'' (plural ''tibiae''), ''tarsus'' (plural ''tarsi''), ''ischium'' (plural ''ischia''), ''metatarsus'', ''carpus'', ''dactylus'' (meaning finger), ''patella'' (plural ''patellae''). Homologies of leg segments between groups are difficult to prove and are the source of much argument. Some authors posit up to eleven segments per leg for the most recent common ancestor of extant arthropods but modern arthropods have eight or fewer. It has been argued that the ancestral leg need not have been so complex, and that other events, such as successive loss of function of a ''Hox''-gene, could result in parallel gains of leg segments. In arthropods, each of the leg segments artic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
