Hamulus
Encyclopedia
Hamus, Hamulus and words derived from them, are morphological
or anatomical
terms in various branches of biology
. They describe structures functioning as, or in the form of, hooks or hooklets.
, in which Hamus means "hook". The plural is hami.
Hamulus is the diminutive
- hooklet or little hook. The plural is hamuli.
Adjectives are hamate and hamulate, as in "hamulate wing-coupling", in which the wings of certain insects in flight are joined by hooking hamuli on one wing, into folds on a matching wing. Hamulate can also mean "having hamuli". The terms "hamose", "hamular" "hamous" and "hamiform" also have been used to mean "hooked", or "hook-shaped". Terms such as "hamate" that do not indicate a diminutive usually refer particularly to a hook at the tip, whereas diminutive terms such as hamulose tend to imply that something is beset with small hooks.
anatomy, a hamulus is a small, hook-shaped portion of a bone, or possibly of other hard tissue.
In human anatomy, examples include:
. Hami might be actual evaginations of the whole thickness of the exoskeleton. The best-known examples are probably the row of hamuli on the anterior
edge of the metathoracic
(rear) wings of Hymenoptera
such as the honeybee. The hooks attach to a fold on the posterior
edge of the mesothoracic
(front) wings.
It is less widely realised that similar hamuli, though usually fewer, are used in wing coupling in the Sternorrhyncha
, the suborder
of aphid
s and scale insect
s. In the Sternorrhyncha such wing coupling occurs particularly in the males of some species. The rear wings of that suborder frequently are reduced or absent, and in many species the last vestige of the rear wing to persist is a futile little strap holding the hamuli, still hooking into the fold of the large front wings.
In those Springtails (Collembola)
that have a functional furcula, the underside of the third abdominal segment
bears a hooked structure, variously called the retinaculum
or hamula. It holds the furcula ready for release in times of emergency.
The terms also are used in descriptive anatomy of some insect genitalia, such as hamuli in various Odonata
and "hamus" for the hooked part of the uncus in male Lepidoptera
.
such words largely refer to hooked bristles such as the hooks on the rachilla of Uncinia
, which attach the fruit to passing animals, or the similarly functioning hooks on Burdock
s, well known as the alleged inspiration for Velcro
.
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
or anatomical
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
terms in various branches of biology
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
. They describe structures functioning as, or in the form of, hooks or hooklets.
Derived terms
The terms are directly from LatinLatin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
, in which Hamus means "hook". The plural is hami.
Hamulus is the diminutive
Diminutive
In language structure, a diminutive, or diminutive form , is a formation of a word used to convey a slight degree of the root meaning, smallness of the object or quality named, encapsulation, intimacy, or endearment...
- hooklet or little hook. The plural is hamuli.
Adjectives are hamate and hamulate, as in "hamulate wing-coupling", in which the wings of certain insects in flight are joined by hooking hamuli on one wing, into folds on a matching wing. Hamulate can also mean "having hamuli". The terms "hamose", "hamular" "hamous" and "hamiform" also have been used to mean "hooked", or "hook-shaped". Terms such as "hamate" that do not indicate a diminutive usually refer particularly to a hook at the tip, whereas diminutive terms such as hamulose tend to imply that something is beset with small hooks.
Anatomy
In vertebrateVertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...
anatomy, a hamulus is a small, hook-shaped portion of a bone, or possibly of other hard tissue.
In human anatomy, examples include:
- pterygoid hamulusPterygoid hamulusThe medial pterygoid plate of the sphenoid curves laterally at its lower extremity into a hook-like process, the pterygoid hamulus, around which the tendon of the Tensor veli palatini glides.-External links: *...
- hamulus of hamate boneHamulus of hamate boneThe volar surface of the hamate bone presents, at its lower and ulnar side, a curved, hook-like process, the hamulus, directed forward and lateralward....
- lacrimal hamulusLacrimal hamulusThe posterior lacrimal crest, with a part of the orbital surface immediately behind it, gives origin to the lacrimal part of the Orbicularis oculi and ends below in a small, hook-like projection, the lacrimal hamulus, which articulates with the lacrimal tubercle of the maxilla, and completes the...
Arthropoda
In arthropod morphology hamuli are hooklets, usually in the form of projections of the surface of the exoskeletonExoskeleton
An exoskeleton is the external skeleton that supports and protects an animal's body, in contrast to the internal skeleton of, for example, a human. In popular usage, some of the larger kinds of exoskeletons are known as "shells". Examples of exoskeleton animals include insects such as grasshoppers...
. Hami might be actual evaginations of the whole thickness of the exoskeleton. The best-known examples are probably the row of hamuli on the anterior
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
edge of the metathoracic
Metathorax
The metathorax is the posterior of the three segments in the thorax of an insect, and bears the third pair of legs. Its principal sclerites are the metanotum , the metasternum , and the metapleuron on each side...
(rear) wings of Hymenoptera
Hymenoptera
Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. There are over 130,000 recognized species, with many more remaining to be described. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and...
such as the honeybee. The hooks attach to a fold on the posterior
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
edge of the mesothoracic
Mesothorax
The mesothorax is the middle of the three segments in the thorax of an insect, and bears the second pair of legs. Its principal sclerites are the mesonotum , the mesosternum , and the mesopleuron on each side...
(front) wings.
It is less widely realised that similar hamuli, though usually fewer, are used in wing coupling in the Sternorrhyncha
Sternorrhyncha
Sternorrhyncha is a suborder of the Hemiptera which contains the aphids, whiteflies, and scale insects, groups which were traditionally included in the order Homoptera. "Sternorrhyncha" refers to the rearward position of the mouthparts relative to the head...
, the suborder
Taxonomic rank
In biological classification, rank is the level in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, and class. Each rank subsumes under it a number of less general categories...
of aphid
Aphid
Aphids, also known as plant lice and in Britain and the Commonwealth as greenflies, blackflies or whiteflies, are small sap sucking insects, and members of the superfamily Aphidoidea. Aphids are among the most destructive insect pests on cultivated plants in temperate regions...
s and scale insect
Scale insect
The scale insects are small insects of the order Hemiptera, generally classified as the superfamily Coccoidea. There are about 8,000 species of scale insects.-Ecology:...
s. In the Sternorrhyncha such wing coupling occurs particularly in the males of some species. The rear wings of that suborder frequently are reduced or absent, and in many species the last vestige of the rear wing to persist is a futile little strap holding the hamuli, still hooking into the fold of the large front wings.
In those Springtails (Collembola)
Springtail
Springtails form the largest of the three lineages of modern hexapods that are no longer considered insects...
that have a functional furcula, the underside of the third abdominal segment
Abdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
bears a hooked structure, variously called the retinaculum
Retinaculum
Occurs where in some places, groups of tendons from separate muscle pass under a band of connective tissueRetinaculum, from the Latin verb retinere , plural: retinacula may be:* In the wrist:** Flexor retinaculum of the hand...
or hamula. It holds the furcula ready for release in times of emergency.
The terms also are used in descriptive anatomy of some insect genitalia, such as hamuli in various Odonata
Odonata
Odonata is an order of insects, encompassing dragonflies and damselflies . The word dragonfly is also sometimes used to refer to all Odonata, but the back-formation odonate is a more correct English name for the group as a whole...
and "hamus" for the hooked part of the uncus in male Lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
.
Botany
In BotanyBotany
Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...
such words largely refer to hooked bristles such as the hooks on the rachilla of Uncinia
Uncinia
Uncinia is a genus of flowering plants in the family Cyperaceae, known as hook-sedges in Australia and as hook grasses or bastard grasses in New Zealand...
, which attach the fruit to passing animals, or the similarly functioning hooks on Burdock
Burdock
Burdock is any of a group of biennial thistles in the genus Arctium, family Asteraceae. Native to the Old World, several species have been widely introduced worldwide....
s, well known as the alleged inspiration for Velcro
Velcro
Velcro is the brand name of the first commercially marketed fabric hook-and-loop fastener, invented in 1948 by the Swiss electrical engineer George de Mestral...
.