Like vampires, most leeches feed by sucking blood from their hosts they are sanguivorous. They generally attach themselves to their meal with their anterior sucker, and some have a proboscis they insert into their prey from their mouth. Others may use strong jaws to cut into through the tissues of their prey.
A third type of leech doesn't have jaws, so it must feed by swallowing small prey items whole. Like worms, leeches are hermaphroditic also called monoecious —they have both male and female sexual organs. Leeches can only reproduce sexually, and unlike some worms, they are not capable of regeneration. Like earthworms, they have a clitellum, which is a region of thickened skin that in leeches is only obvious during the reproductive period.
Mating typically involves the intertwining of bodies where each leech deposits sperm in the others' clitellar area. The sperm then make their way to the ovaries for fertilization.
The fertilized eggs are deposited in a tough gelatinous cocoon that is secreted by the clitellum and contains nutrients for the developing leeches. The cocoon is either buried in mud or affixed to submerged objects, and after several weeks or months the young emerge as small copies of the adults. In the family Glossiphoniidae, many species of leeches attach the cocoons directly to the ventral side of the parent. The parent is able to protect the young as they develop and provide prey for the young leeches after they hatch.
Adult leeches die after they reproduce one or two times. Biopharm suppliers of medicinal leeches since For questions about information on this page, please contact Kate O'Laughlin , Ecologist. Skip to main content Animals, plants and habitat Biodiversity. In fact, leech bites can be quite the opposite of harmful. Physicians have used leeches to treat human ailments as far back as the days of ancient India and Greece.
Back then, physicians thought leeches could remove "bad blood" from a sick patient. Bloodletting as a popular medical procedure went away hundreds of years ago. However leeches have managed to find a new place of honor in modern medicine. Modern scientists have learned that leeches secrete a substance while sucking blood that acts as an anti-coagulant. This substance helps to increase blood flow and keep blood from clotting.
Advanced procedures, such as skin grafting, plastic surgery, and reattachment of body parts, have benefitted from the use of leeches to prevent clotting and keep blood flowing to sensitive areas after surgery. Without the use of leeches, many of these surgeries would fail due to blood clots and restricted blood flow after surgery.
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Want to add a little wonder to your website? Help spread the wonder of families learning together. We sent you SMS, for complete subscription please reply. Follow Twitter Instagram Facebook. Where do leeches live? What do leeches eat? Are leeches dangerous? Wonder What's Next? Try It Out Are you ready to learn more about leeches? Grab a friend or family member and check out the following activities: Someone who constantly borrows money or food from others is sometimes called a leech.
Knowing what you now know about leeches, you can probably understand where this nickname comes from. What other animal nicknames can you think of? What images come to mind if someone calls you a bulldog, a pig, or a sloth? Share your thoughts with a friend or family member. What other animal nicknames can they think of? Can you believe that leeches are still used today in some countries as a form of medicine or therapy?
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After all, they're certainly not cute and cuddly. Nothing is known of the internal anatomy of P. Moore stated that tfie denticles, as orgim'ally described for P. He indicated the dentition as partTy distichodont. Carolina, indicated only a single row monostichodont of 20 acute teeth, with no indication of distichodonty. Therefore, the variability in the number of teeth suggests it is a poor diagnostic character for the two species.
However, the internal anatomy of these specimens has not been studied. The variability of teeth and color of these forms indicate that there is considerable doubt that Philobdella is represented in the southern states as two species. A comparison of the internal anatomy of the two forms would resolve the question. Blanchard, , Erpobdella de Blainville, , and Mooreobdella Pawlowski , sustained a number of changes over the yeaFs"! The Dina-Erppbdella complex still remains unresolved.
Sawyer and I Klemm, have discussed the taxonomic characters that have caused the confusion. In Sawyer's opinion personal communication the genus Dina does not actually occur in North America. Moore , Meyer , Sawyer , Sawyer and Shelley , and I Klemm, consider Mooreobdella a distinct genus, endemic to North America, and consists of five species: bucera Moore, ; fervida, Verrlll, ; melanostoma, Sawyer and Shelley, ; microstoma, Moore, ; and tetragon, Sawyer and Shelley, A subspecies, Erpobdella punctata annulate, of E.
Meyer and Moore reported finding both subspecies throughout Canada, and I Klemm, a,b have reported these forms from Michigan, Washington, and Oregon.
Moore Soos a , Davies , I Klemm, a,b retained this color form at the subspecies level. During this study, I found no evidence of anatomical Difference between the two forms, other than color and size, and recognize the synonymy of Sawyer Dina lateralis Verrill , a poorly described species, was relegated to synonym under Erpobdella punctata punctata by Sawyer Soos a and Klemm b retain the species, based on Moore's interpretation , of the species, as D.
Moore's vague description of the morphological type states that the species has no eyes, the gonopores are separated by two annuli, and the body is colored with longitudinal stripes.
However, nothing is known of its internal reproductive system. Sawyer personal communication stated he had collected specimens from San Diego with three pairs of eyes. Based on information from Moore ; Soos , Sawyer personal communication , as well as an examination of preserved material, the following is a more complete description for j.
Atrium Fig. I have not seen fresh material, but the ground color of specimens preserved in alcohol is dull yellowish gray, immaculate below and on the margins, but largely replaced above by four longitudinal stripes vague in some specimens of grayish or dull black. The outer pair of stripes is submarginal, duller in color, and narrower than the more distinct inner pair, which is separated by a median stripe of ground color.
However, the identification of a few species of Haemopis and some Erpobdellidae, especially species of the genera Mooreobdella and Dina, may require dissection. If reference is made in a couplet to an internal feature after reference to an external one, the key can be used first for the identification of some specimens without resorting to dissection, provided the external characters are clearly discernible.
Also, some collections will contain specimens that can not be identified to the species level for various reasons, but they should be identified to the lowest taxonomic category taxon possible, based only on characters of the specimen used in the key.
A glossary of diagnostic terms has been provided. The external diagnostic features which are important for identifying the leeches are: presence or absence of chaetae in the cephalic region, size of mouth, general shape of body, form of suckers, form of cephalic region, number and arrangement of eyes, presence or absence of jaws and number of teeth denticles , eyespots ocelli , papillae, pulsatile vesicles, sensillae, digitate processes on rim of caudal posterior sucker, caudal sucker separated from body on narrow pedicle peduncle , copulatory gland pores, the number of annuli per somite segments and between gonopores, and the pigmentation patterns.
Only seven internal characters are used in the key, four of which are used to determine certain species of Haemopis: the presence or absence of jaws, the number of teeth denticles per jaw, the velum, and the internal ridges of the pharynx. The shape of atrium and atrial horns, and the length of the ejaculatory ducts are three other internal anatomical parts used in the identification of some species of erpobdellids.
Biological characters useful for the identification of specimens include hosts, methods of feeding, the manner of locomotion, and caring for eggs and young, and ecological and geographical variations. Each somite contains a ganglion in the central nervous system. Each neuromeric somite is divided externally by superficial furrows into annuli or rings.
Incomplete or abbreviated somites occur at both ends of the body. The annul i are best seen after careful narcotization or proper preservation. Reference to annulation in the key is always to complete somites, and with the aide of a dissecting stereomicroscope the outline of the annuli can be seen most easily in the lateral margins of the ventral surface.
Moore and Castle independently recognized that the nerve cord ganglia are located in the middle annulus of the somite, and that the triannulate somite is the basic form. In the 3-or 5-annulate somite for example, the middle annulus is aligned with the ganglion and is known as the neural or sensory annulus.
The annulation suggested by Moore Table 1 is used throughout the key. Counting from the cephalic end, the triannulate somite consist of three primary annuli best seen in middle of body , numbered al, a2, and a3 or sometimes written al Annulus a2 the neural annulus contains the ganglion and is marked externally by transverse rows of minute, cutaneous sensillae segmental receptors , which are difficult to see in some specimens.
Repeated bissection of the three primary annuli give rise to more complex annulation. Table 1. Theoretical table of the annuli produced by repeated bisection of the three primary annuli after Moore, 1 In addition to "their hirudinean characters, these species show their peculiarity by possessing some oligochaete-like evolutionary traits.
Externally, the main anatomical character that separates the Acanthobdella from all other leeches is the presence of chaetae setae in the first five anterior somites Fig. The last four somites are united to form a small caudal sucker which has its concavity directed posteriorly. The chaetae bundles, consisting of two pairs 10 pairs in all Fig.
In some individuals the body can have dark transverse bands, and sometimes these bands occur over the entire body. Preserved specimens often lose their color and become whitish in appearance. In addition to the sensillae, which are confined to the sensory annuli, other visible organs of the integument are the cephalic eyes ocelli and papillae tubercles.
Eyespots when present on the caudal sucker and lateral margins Fig. Varying in number and shape punctiform, crescentiform , eyespots are used in the identification of some species of piscicolids.
They are absent in the Glossiphoniidae. The number and position of the eyes of the cephalic anterior region are important taxonomic features. The relative distance between eyes is another important diagnostic character in identification.
If the distance between them is equal to or greater then the diameter of the eyes, they are termed "well separated" Fig. If they touch, they are termed "fused" or "confluent" Fig. If the distance between a pair of eyes is less then the diameter of a single eye, they are termed "close together" Fig.
However, some variation in eye location can occur ocasionally, as a result of rapid preservation. The eyes are arranged in separate labial and buccal groups Fig. If the leech has been fixed and the eyes cannot be seen, the head of small specimens can be flattened between two glass slides, which will generally make the eyes visible. Amman's lactophenal is prepared as follows: lOOg phenol, ml lactic acid, ml glycerine, mL water. They may be limited to small, minute protrusible sense organs that are often scattered in small and great numbers over the dorsal surface, or are large tubercle-like smooth, conical, or rounded cone projections that include some of the dermal tissue and muscles, and which are often themselves covered with minute papillae.
The segmental arrangement of the papillae is an important characteristic used in distinguishing between certain species of Helobdella and Placpbdella, and also separating Glossiphom'a complanata from Boreobdella verrcuata. A reliable characteristic for IK verrcuata is the large and distinct papillae on the 2nd and 3rd rings of the somite Fig.
In Helobdella triserialis, the papillae are small, smooth, and conical in three or less longitudinal rows. Numerous large and scattered papillae are present on the dorsum of Placobdella ornata, and the surface of these papillae is covered with minute papillae which results in a very rough or warty appearance. However, in specimens of the above species, variation occurs in these chararacters, and they must be used with other features such as shape and pigmentation, as indicated in the key.
The anterior sucker of the piscicolids is always expanded and usually distinctly marked off from the bocly, and the mouth pore is in the middle of the sucker Figs. In Erpobdellidae and Hirudinidae, the mouth is medium to large in size and the anterior sucker is little more than the expanded lips of the mouth opening Fig. Caudal Region-- The form of the caudal posterior sucker is characteristic of some leech species, and is included in the key as a diagnostic feature.
Species of Actinobdella possess digitate processes glands and papillae on the rim of the caudal sucker Figs. In preserved specimens, the digitate processes are usually retracted. They are finger-like when everted Fig. The position of the digitate processes is indicated on the dorsal surface of the caudal sucker by faint radiating ridges Figs. In Batracobdella cryptobranchii and Placobdella pediculata, the digitate processes are absent, but the posterior sucker is separated from the body on a narrow pedicel Figs.
Other minor characters not discussed here will be found appropriately in the key. However, the separation of these two regions is less conspicuous and not always observible in preserved specimens of Piscicola, but they are always present in Cystobranchus.
Some preserved specimens of Myzobdella and Piscicol aria also show a distinct separation of these two regions due to contraction Fig. In Piscicol a the vesicles are small or usually undifferentiated in preserved specimens Fig. Coloration features, such as blotches, dots, spots, stripes, bands, lines are easy to determine in living as well as freshly preserved specimens, and usually persist for sometime.
They may fade away in some specimens which have been preserved in alcohol or preserved for a considerable length of time. Green and blue pigments are lost almost immediately in alcohol, although they usually persist longer in formalin. The red color of blood is lost almost as soon as the green and blue, and the other reds and yellows are lost more slowly. The browns and blacks usually remain for years. It should be noted, however, that in some species the colors of the dorsal surface change with the development, age, and environmental conditions.
Also, the pigmentation pattern of the dorsal surface in several species is a poor diagnoistic character because several color forms exist.
Size-- The average size of each species is given in the key, but many variations appear in the species due to the age and development of the specimen collected and also due to contraction during processing. Finally, it should be noted again that most specimens of leeches can be identified to the species level.
The key will, however, enable the user to identify these difficult forms to the lowest taxonomic level of which diagnostic characters of the specimen are available to a particular taxa. Internal Features Digestive Tract-- The alimentary canal is a tube from mouth to anus and Is divided into the buccal chamber, pharynx, esophagus, stomach to crop, intestine with or without diverticula, and rectum.
In the Glossiphoniidae and Piscicolidae, the mouth is a small pore on the rim or in the center of the anterior sucker Fig. The pharynx of the Rhynchobdellida is muscular and protrusible through the mouth as a proboscis Fig. The proboscis has a crown-like tip, and is adapted to penetrate both invertebrate and some vertebrate tissues. In Hirudinidae and Erpobdellidae, the mouth is medium to large in size Fig. In the hirudinids, the buccal cavity, which may or may not contain jaws with denticles, is separated from the cavity of the sucker by a flap of skin called the velum Fig.
The shape and form of the anterior sucker, the absence of teeth, the number of internal ridges fleshy pods of the pharynx, and the presence or absence of papillae on the velum are used as diagnostic features to separate Haemppfs pi umbea and Haemppi's grandis.
The velum is finely papillated in H. All other species of Hirudinidae have three muscular jaws, two ventrolateral and one dorsomedial Fig.
The free edge of each bears teeth arranged in either one monostichodont or in two distichodont rows. To examine the velum and jaws Fig. A medial incission should be made from the lower lip of the anterior sucker back far enough for the margins to be pinned out to expose the inner surface of the buccal cavity and pharynx.
Details of the denticles Fig. Reproductive System External Reproductive Features-- The male and female gonopores are visible on the middle of the ventral surface of somites XI and XII and are generally separated by two to seven annuli. Alboglossiphonia heteroclita and Marvinmeyeria lucida are two unusual species in tnat the male and female ducts open into a single gonopore.
The male gonopore is large, more readily visible in the mature specimen, and anterior to the female gonopore. In some specimens the female pore can be difficult to find due to its small size. It is seen most easily immediately after narcotization, and its position often being revealed by a small opening or some color difference which may be lost if the specimen is not properly preserved. Another important characteristic used in determining species of erpobdellids is the number of annuli between the male and female gonopores Fig.
If it is necessary to make evident the female opening, the following procedure has sometimes proven successful. The leech is then placed in creosote-beechwood or Amman's lactophenol clearing agents for 15 to 30 minutes, depending on the size of the leech the larger the leech the longer the time , until the female gonopore begins to stand out. Amman's lactophenol works best with specimens preserved in formalin. Gentle application of heat will speed up the process. The area of the gonopores should periodically be observed under a stereomicroscope, for if the specimens are left too long in the clearing agent, desiccation and wrinkling ensues.
Sawyer indicated that slight variations in the location and number of annuli between gonopores exist in some specimens of Hirudinidae and Erpobdellidae. Meyer and Moore , Sawyer , and Klemm stated that some variation occurs in species of Theromyzon of Glossiphoniidae. Notes on Systematics. External copulatory glands with pores are present in a linear or transverse pattern of either 4, 6, 8, or 28 Fig.
Immature forms may not have a set number of copulatory pores Sawyer and Pass, , but other characters in the key can be used for identification.
The copulatory glands are located on the ventral surface, four to five annuli posterior to the female gonopore. In some immature specimens the copulatory glands and pores are absent and other diagonstic characters are indicated whenever possible in this key for identification. In Philobdella, the gonopores and copulatory pits are surrounded by an undifferiated glandular area Fig. Internal Reproductive Features-- Leeches are hermaphroditic. The female reproductive system is comprised of ovisacs, terminating in ducts which join to form a common duct or vagina.
The male reproductive system consists of testisacs in metameric patterns, five to ten in the Glossiphoniidae and Piscicolidiae and nine to ten in the American Hirudinidae.
But in the Erpobdellidae, they are small, numerous and arranged in grape-like clusters. The vasa deferentia connect the testisacs to the vasa deferens on each side. These ducts lead into the seminal vesicles and ejaculatory ducts, which open into the atrium.
The shape of the atrium is diagonistic for some species of Erpobdellidae Figs. This organ is a medium chamber and consists of three parts: a thin-walled eversible bursa, a thick walled glandular chamber, and a muscular medium chamber, as well as a pair of lateral horns atrial cornua , which receive the ejaculatory ducts. In Nephelopsis obscura, the atrial cornua is spirally arranged like a ram's horn Fig.
In the Mooreobdella and Dina-Erpobdella complex, the atrium is simply curved, globular, rounded, ellipsoidal, or short and curved Figs. Some species also have ejaculatory ducts with or without long preatrial loops Figs. To examine the male reproductive structures Fig. Another method Fig. To accurately Identify small forms of the family Erpobdellidae, a technique which sometimes works is the following: 1 fix the leech in formalin, 2 stain and destain, 3 run through an alcohol series, 4 clear and mount as described earlier, to determine the size and shape of the atrium, atria!
FIG, 2. Diagrams of methods to show male reproductive system of Erpobdellidae: a dash lines indicate cut on dorsal surface, b,c dorsal portion of annuli removed and connective tissure teased away displaying the reproductive structures; d dash lines indicate cut on ventral surface. Order Acanthobdellida, Family Acanthobdellidae Acanthobdella peledina Grube, Chaetae absent from cephalic region of anterior somites; body shape various 2 chaetae FIG.
Acanthobdellidae: a cephalic region, ventral view; bsc general bocjy shape cf. Notes on Identification. Order Rhynchobdellida 3 Mouth opening medium to large, occupying entire oral sucker cavity, forming rounded lips, not pore-like Fig. Ventral views of anterior oral suckers to show mouth and sucker differences: a pore on rim of sucker; b pore within sucker; c pore near center of sucker; d SEM of protruding muscular proboscis cavity of Helobdella triserial is X ; e-h mouth occupying entire sucker cavity.
Family Glossiphoniidae 5 Body at rest cylindrical, narrow, Figs. Family Piscicolidae. General body shapes of Glossiphoniidae in dorsal view: a ovate-lanceolate; b lanceolate; c subcylindrical terete ; d,e various shapes. Glossiphonbiidae, general body shapes ventral view. Glossiphoniidae, dorsal views of eyes: a-f eyes well separated, cepahlic region undifferentiated; g,h eyes well separated, cepahlic region differentiated "discoid head.
General body shapes of Piscicolidae: a-k dorsal view showing body regions, ocelli arrangements, and external structures. General body shapes of PiscicoHdae: a-d Myzobdella lugubris, dorsal view; e,f Pisclcolan'a reducta, dorsal view.
Some attachment sites of fish leeches: a Placobdella pediculata attached under the operculum of the freshwater drum Aplodlnotus grunniens ; b Cystobranchus verrllll attached to the gill arch and body of a flathead catfish Pylodictis o]iva "js ; c Myzobdella lugubris attached to the chin of the channel catfish tlctalurus unctatus ; d Myzobdella lugubris attached to the pectoral fin of a lue gill Lepomjs macrochirusj; e Piscicolaria reducta attached to the caudal fin of a logperch Percina caprodes.
Part of the operculum and gill a was removed to show attachment location. Illustrations b-e after Poe, Order Gnathobdellida, Family Hirudinidae 43 Eyes, 0, 3, or 4 pairs in separate labial and buccal groups Fig. Order Pharyngobdellida, Family Erpobdellidae. Arrangement of eyes, dorsal view: a Hirudinldae: b-d Erpobdellidae.
General body shapes: a-e H1rud1nidae; f-j small hirudinlds; f-j Erpobdellldae. Placobdella montifera Moore, Dorsum smooth; eyes one pair, separated by their diameter; color greenish-gray; free-living, parasitic on fish; length mm Fig. Placobdella montifera: a normal resting shape; b contracted shape.
PTacobdel1 a nuchalis. Helobdella 11 Dorsal and ventral surfaces heavily pigmented with uniform, minute, blackish chromatophores, with thin dark paramedial lines extending into anterior region; dorsal surface smooth, no papillae or scute; crop caeca 6 pairs, gonopores united; length mm Fig.
Placobdella hollensls. Marylnmeyerla luclda. Helobdella stagnalIs. Helobdella elongate. Castle, 14 13 Dorsum with transverse rusty-brown, interrupted bands alter- nating with irregular whitish bands, the latter consisting of 8 to 10 confluent white metameric spots on each neural annul us; length 10 mm Fig.
Helobdella transversa Sawyer, Dorsum without. Helobdella elongata. Helobdella transversa. Helobdella fusca" a typical pigmented form; b non-pigmented form; c scattered pigmented form; d,e white blotched pigmented form.
Helpbdella papillata. Helobdella tnsenalis: a,b showing variability of [Dapmae and pigmentation. Helobdella triserial is: a-c showing variability of papillae and pigmentation.
Helobdella triserial is: a,b showing variability of papillae and pigmentation. Batracobdella phalera Graf, 18 17 Body ovate-lanceolate, excessively flattened, thin, with 5 sometimes raised longitudinal rows of white prominences surrounded by yellowish dots, equidistant longitudinally and transversely; length mm Fig.
Batracobdella michiganensis. Actinobdella 21 Without digitate processes on caudal sucker 22 31 32 pedicel- digitate processes pedicel 33 retracted digitate processes c v digitate processes FIG. Caudal sucker and slender stalk pedicel of Placobdella pediculata: a lataeral view; b ventral view.
Caudal sucker, short pedicel, of Batracobdel1 a cryptobranchii, lateral view. Actianobdella annectens, dorsal view of caudal sucker showing digitate processes. Actinobdella inequiannulata, dorsal view showing middorsal ridge. Actinobdella InequTannulata, ventral view of engorged adult.
Actlnobdella 1nequiannulata, dorsal view with minute papillae. Placobdella pediculata, dorsal view of juvenile without slender stalk pedicel. Placobdella pediculata. Placobdella pediculata, dorsal view of contracted adult. Batracobdella cryptobranchTi, dorsal view.
Placpbdella parasitica, ventral view showing striping. FIG, Placobdella parasitica:Ta,b dorsal view showing variable pigmentation patterns. Placobdella parasitica: a-c dorsal view showing variable pigmentation patterns.
Oligobdella biannulata. Placobdella ornata, ventral view. Placobdella ornata: a,b dorsal view snowing variability of papillae and pigmentation. Placobdella papillifera: a,b ventral view showing striping, FIG. PIacobdelTa papi 11 iTera'. PlacobdelJa papillifera From Sawyer and Shelley, Placobdella multi1ineata: a,b dorsal view showing variability in papillae and pigmentation. Alboglossiphom'a, Glossiphonia, and Boreobdella. With 4 pairs of eyes Fig.
Batracobdella paludosa. Alboglossiphom'a heteroclita": a,b variable pigmented forms. Alboglossiphonia heteroclita: a-c variable plgmented forms. Glossiphonia complanata Linnaeus, Dorsum always with large and distinct papillae at median of the 2nd and 3rd annuli of the triannulate somite Fig.
Schematic view of two nrfddorsal segments: a Glosslphom'a complanata; b Boreobdella yerrucata. Glossiphom'a comjjlanafa'. Boreobdella verrucata. Theromyzon biannulatum or Theromyzon rude: pigmentation. Theromyzon tessulatum: a,b variations in pigmentation. Piscicolaria reducta: a-c variable bocty shapes. Myzpbdsella lugubris, variable body shape.
Hyzobdella Tugubris: a-d variable body shapes. Cystobranchus 37 Pulsatile vesicles usually small, each covering 2 annull, obscure, difficult to see after preservation of specimens Figs.
Piscicola 40 37 36 With eyespots ocelli on caudal sucker Fig. Dorsal view of caudal sucker of Piscicolidae: a,b punctiform eyespots only; c crescentiform eyespots and pigmented rays; d punctiform eyespots and pigmented rays; e-g eyespots ocelli absent. Cystobranchus meyeri: a lateral view showing eyespots on body region and caudal sucker; b dorsal view. Cystobranchus virginicus. Cystobranchus mamminatus.
Cystobranchus verrillt: a unpigmented fonn; b plgmented form. Plsclcola punctata, 41 40 With punctiform eyespots on caudal sucker Fig. Pisclcola salmositica. Piscicola milnerl. Piscicola geometra. Macrobdella 44 Without copulatory gland pores on ventral surface Figs.
Haemppis terrestris; h Haemopis septagon. Philobdella 48 Lacking glandular area around gonopores; gonopores separated by annuli Fig. Macrpbdella dltetra; a,b variable pigmented forms. FIG Macrobdella sestertla. Macrobdella decora, FIG.
Macrobdella djplotgertia. Haemopls 50 Dorsum with 4 or 6 longitudinal reddish-yellow stripes forming an ornate pattern on dorsum; color pattern variable, greenish with irregular black margins; ventral surface black with white and gray markings; probably not established in North America, sometimes purchased in drug stores; length, to mm Fig. Philobdella floridana. Hirudo medicinal! Philobdella gracills. Haemopis kingi Mathers, 53 51 With jaws and teeth Fig. Haemopis lateromaculata Mathers, Jaws with pairs of teeth; gonopores separated by 5 annuli; color variable, usually olive-green, yellowish-gray with moderate to heavy black mottling or blotched dorsally and ventrally; or uniform slate gray with few irregular black blotches, resembling H.
Haemopis terrestris: a adult; b juvenile. Haemppis kingi: a dorsal view of tw checkerboard color pattern; b adult. Dissected mouth and buccal cavity: a,b Haemopi's marmorata, ventral view; c Haemopis marmorata, pharynx and associated structures; d Haemopi's marmorata, teeth and jaw, lateral view; e location of velum and pharynx, without teeth and jaws, ventral view; f Haemopis plumbea, dissected pharynx: g Haemopis grandis, dissected pharynx. The pharynx f,g is shown as opened along the midventral line, centered on the middorsal line.
Haemopis piumbea, oral sucker. Haemopis plumbea. Haemppis grandis, variable forms: a dark colored, heavy spotted, blotched phase; b light colored, irregularly spotted, blotched phase; c dark colored immaculate phase. Dorsal view of dissected male genital atarium and ejaculatory ducts with or without long preatrial loops: a Hooreobdel1 a melanostoma; b Erpobdella punctata punctata or ErpobdeTja punctata coastal isinc inmature, Erppbdella punctata punctata; td Dina anoculata"; e Mooreobdella bucera; f Mooreobdella fervida; tg,h c.
XII, twelfth Mooreobdella microstoma. Dorsum either lacking pigment, uniform gray pale red or darker clouding, sometimes with minute black pigment or pigmented with two narrow or broad, dark longitudinal stripes extending over entire body, including always lighter median stripe.
Erpobdella punctata punctata Leidy, With 4 longitudinal stripes on dorsal surface of grayish or dull black, of which outer pairs, submarginal, duller in color, and narrower than more distinct inner pair, well separated by a median stripe of ground color or lacking pigment, uniform gray; eyes lacking or 3 pairs; no sensillae on annuli; gonopores separated by 2 annuli in furrows Fig.
Hooreobdella melanostoma. Erpobdella punctata coastalls. Dina anoculata. Mooreobdella bucera. Hooreobdella bucera Moore, Gonopores separated by 2 annuli, usually in furrows Fig. Hooreobdella fervida Verrill, 63 58 Gonopores separated by 3 annuli, usually in furrows Fig.
Hooreobdella tetragon. Dorsal view of dissected male genital atrium and ejaculatory il loops: a,b Nj dubia; d Dina parva. XII, twelfth" ducts with long preatrial loops: a,b Nephelopsis obscura; c Dina na parva. Dlna dubla. Accessory Eyes: A series of supplementary eyes ocelli behind the single pair of functional eyes in the cephalic region of Placobdella hollensis.
Annuli sing. Annul us : External body rings or superficial transverse Basically there are 3 primary annuli tri- furrows of the somites, annulate per somite, labelled by convention as al, a2, a3 or sometimes written al-3 , except in Ollgobdella biannulata which has biannulate somites. In some genera of leeches, each annul us may be subdivided see Table 1 into secondary annuli, bl, b2, b Each somite corresponds with one ganglion in the central nervous system.
The ventral nerve cord ganglia are placed in the middle annulus of the somite. Annulation can be most easily seen in the lateral margins of the middle region of the body.
Anterior sucker: Oral sucker. Atrium: A variously shaped, male reproductive organ, consisting of three parts: a thin-walled eversible bursa, a thick walled glandular and muscular medium chamber, and a pair of atrial cornua openings into the latter of similar structures of the male reproductive system.
The atrium opens externally through the male gonopore. Buccal cavity: Mouth cavity. Bulbous: Bulb shape Figs. Caudal ocelli: Dot-like or crescent-shaped eyespots on the caudal sucker of certain piscicolids. See punctiform and crescentiform ocelli. Caudal sucker: Posterior sucker. Cephalic Region: Head region. Chaetae sing. Chaeta : Hair or bristle-like structures of some classes of Annelida. The term setae, however, seems to dominate recent English language publications.
CliteTliim: A regional epidermal saddle or swollen glandular portion of the integument in the area of the gonopores of certain leeches, especially the Hirudinidae and Erpobdellidae, visible in adults during the breeding period.
It contains gland cells that secrete material to form cocoons. Complete somites: Segments having the full number of annuli or body rings characteristic of the genus.
Copulatory depressions: A glandular area around the gonopores and copulatory pits on the ventral surface in Philobdella. Copulatory gland pores: Pores present in a linear or transverse pattern of either 4, 6, 8 or They are located on the ventral surface, 4 or 5 annuli, posterior to the female gonopore in Hacrobdella. Copulatory pits: Thick depressions and prominences of the glandular area around the gonopores of Philobdella.
See copulatory depressions. Crescentiform ocelli: Crescent-shaped or crescentric eyespots on the caudal sucker of Piscicola salmositica. Crop Stomach : Sac-like dilatation or largest part of the alimentary canal adapted for storage of blood, and so on; may be a single, straight tube, or contain several paired diverticula.
Crop caeca: Segmental pouches or diverticula of the crop stomach. Denticles: Small teeth-like processes; two rows of teeth distichodont wholly or partly in Phi'lobdella and some species of Haemopis or one row of teeth monostichodont in Hirudo and Hacrobdella. Digitate processes: A marginal circle of retractable processes, finger! The digitate processs are usually retracted in preserved specimens but their position is evident by faint radiating ridges or bands visible on the outer rim of the caudal sucker.
Discoid head: The oral sucker and cephalic region widely expanded, circular and demarcated from the body by a constriction; in Placobdella montifera and Placobdella nuchal is. Erpobdellid pi. Eyes Ocelli : Photoreceptors confined to the cephalic "head" region, formed from a number of light sensitive cells eyespots backed by a pigmented cup. The eyes are located on the dorsal or lateral surface of the anterior segments, are segmental, vary in number and arrangement. Ganglia sing.
Ganglion : Concentration of nerve cell bodies In the ventral nerve cord. The neural annulus of segment somite 10 would, therefore, be expressed as Xa2 of the triannulate somite. Gonopores: External openings of the reproductive tracts, located on or in the furrow of the annulus on the midventral surface of somite XI and XII about one third from tip of cephalic region. The male gonopore is anterior to, larger than, and more conspicuous than the female gonopore. The male and female gonopores generally are separated by or more annuli but in a few species open into a common gonopore.
Glosslphom'ld pi. Hirudim'd pi. Hiradtm'dae: The widely accepted familial name based etymologically on the stem hlrudlnls, the Latin genitive singular of hirudo. It should always be used in preference to Hirudidae Art. A treatise on leeches. Incomplete abbreviated somites: Occur at both ends of the body of leeches and may have any number of annul 1 less than the complete somites into which they grade.
Integument: A general term for the covering, or outer layers of an animal. The purpose of the integument is for defense and sensing environmental conditions. Internal ridges: Fleshy anatomical structures of the pharynx in Hirudinidae. Sometimes called pharynx folds or pods. Jaws: Three large, oval bladelike jaws shaped like a half circular saw occurs just within the mouth cavity of some species of GnathobdelHda. Each bears along the edge a large number of small teeth denticles. The three jaws are arranged in a triangle, one median dorsal and the other two ventrolateral.
They have a covering of cuticle, and along the free edges of the disc it 1s thickened to form rows of numerous, minute teeth monostichodont or distichodont. Lateral ocel Eyespots on the urosome of Cystobranchus meyerl. Leech: Any segmented worm with terminal suckers used for attachment and locomotion; the various species may be parasites blooding sucking , predators, or scavengers; most are aquatic in North America. Metameric: Referring to metamerism or segmentation. Metameric dots, spots, patches, or prominences: Yellowish or whitish areas usually metamerically segmentally arranged; some represent sensillae or segmental receptors.
Neural annul us Sensory annul us : The annul us aligned with the ganglion in the central nervous system. Nephridiuml: Excretory organs, usually that of macroinvertebrates. Nuchal plate: See scute. Ocelli sing. Qcellus : Eyespots found in cephalic, caudal ends, or lateral margins of body of certain leeches.
They may be found singly in any body part, including the caudal sucker and lateral margins, and aggregations of them in a common network of chromatophores usually form eyes of piscicolids. Eyes of leeches are confined to the cephalic "head" region and are segmental in some species.
Such eyes are simple when single, and compounded, such as Placobdella, when one or two small ones are attached to the main one. Oculiform spot: See punctiform ocelli, Oral sucker: Anterior sucker. Papillae: Small to large protrusible sensory organs scattered or in a metameric series on the dorsal surface of the leech and thought to be tactile in function.
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