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Invertebrate Circulatory Systems

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Abstract

The sections in this article are:

1 Protozoa and Parazoa
2 Cnidaria
3 Platyhelminthes
4 Nemerteans
5 Annelids
5.1 Polychaetes and Oligochaetes
5.2 Hirudinea
6 Molluscs
6.1 Heart and Vascular Performance
7 Arthropods I: Onychophorans
8 Arthropods II: Chelicerates
8.1 Limulus
8.2 Scorpions
8.3 Spiders
9 Arthropods III: Uniramia
9.1 Myriapods
9.2 Chilopods
9.3 Insects
10 Arthropods IV: Crustaceans
10.1 null
11 Echinoderms
11.1 null
12 Pogonophora
13 Vestimentifera
14 Hemichordates
15 Urochordates
16 Cephalochordates
17 Conclusion
Figure 1. Figure 1.

Path of extracellular fluid movement through simplest internal circulatory systems, digenean trematode flatworm Cotylophoron.

Modified from
Figure 2. Figure 2.

Range of circulatory systems seen in nemertean worms A: Cephalothrix. B: Tubulanus.

From
Figure 3. Figure 3.

A: Drawing of blood vascular system of a polychaete annelid worm Amphitrite. Abbreviations: abv, afferent branchial vessels; as, anterior stomach; d, diaphragm; drv, dorsal ring vessels; ds, diaphragm sac; dv, dorsal vessel; e, esophagus; elor, efferent bronchial vessel; g, gills; gs, gut sinus; h, heart; i, intestine; lm, longitudinal muscles; Iv, lateral vessel; n, nephridium; ph, pharynx; pi, posterior intestine; pr, prostomium; ps, posterior stomach; s, septa; srv, segmental ring vessel; sv, subintestinal vessels; vg, ventral glands; vrv, ventral ring vessels B: Drawing to show segmental organization of the blood system in an errant polychaete. Abbreviations; dbv, dorsal blood vessel; i, intestine; lm, longitudinal muscle; pv parapodial vessels; vnc, ventral nerve cord; vbv, ventral blood vessel. The elaborate circulatory supply in the parapodium is for gas exchange.

From
Figure 4. Figure 4.

A: Sections of the vascular and coelomic sinus systems of the Hirudinea (leeches). In the “primitive” leech, Placobdella costata, the dorsal and ventral coelomic sinuses (ds, dorsal sinus; vs, ventral sinus) surround the much reduced dorsal and ventral vessels (dv and vv, respectively). Other labeled structures: is, intermediate sinus; ls, lateral sinus (= LH); nc, ventral nerve cord; vs, ventral sinus. B: Coelomic sinus system of the leech Hirudo medicinalis, in which all traces of the original dorsal and ventral vessels are lost. Abbreviations: lds, laterodorsal sinus; lls, laterolateral sinus; lvs, lateroventral sinus; nc, nerve cord; sl, subepidermal lacunae; t, testis.

From
Figure 5. Figure 5.

Structure and innervation in lateral hearts of the leech Hirudo. A: Regional differentiation in cardiac myocytes of leech lateral heart. Structure of two muscle cells pressure injected with Lucifer yellow. The cell on left is in trans form, while one on right is in cis form. Scale bar 50 μm.

From .] B: Reconstruction of cis‐configuration muscle cell after cobalt staining and sectioning, showing its orientation along axis of lateral heart [From .] C: Location of sphincter valves in one midbody segment of a lateral vessel (posterior to region called heart) wall of the leech Hirudo with rostral end opened dorsally. Abbreviations: c, caudal; las, lateral abdominal sphincter; lav, lateral abdominal vessel; ldv, lateral dorsal vessel; llv, latero‐lateral vessel; lv, lateral vessel (heart); r, rostral; s, main sphincter; v, valve. Arrows indicate direction of flow. [From
Figure 6. Figure 6.

A: Schematic drawing of relationship between ventral nerve cord and lateral hearts of H. medicinalis.

From .] B: Example of entrainment of myogenic rhythm of leech lateral heart muscle by HE motor neuron bursts. The heart rhythm is normally phase‐locked with HE cell activity rhythm. When HE cell was hyperpolarized, lateral heart muscle innervated by this neuron continued to beat rhythmically, but at slightly slower rate. After about 40 s of hyperpolarization, antidromically conducted action potentials appeared in HE cell as peripheral neurogenic rhythm began to be expressed (open arrows). At the solid arrow a relatively strong neurogenic burst reset myogenic rhythm. When HE cell was released from hyperpolarization it again entrained the muscle to its own rhythm. Solid dots indicate expected time of myogenic bursts. Open dots indicate actual time bursts entrained by HE cell. CM, current monitor; HE, heat excitation motoneuron; L, 4, location of recording electrode; nA, nanno‐amps; left = 4th ganglion. [From
Figure 7. Figure 7.

Scheme of the circulatory system of the leech H. medicinalis. A: Six fused anterior segments. B: Scheme valid for the 21 somatic segments. C: Scheme valid for segments that contain the intestine. D: Seven fused posterior segments. Abbreviations: ci, capillary network of intestine; dbw, capillary segments of dorsal body wall; dv, dorsal vessel; HIP, direction of blood flow in high‐pressure phase; iv, lateral intestinal vessel; lav, lateral abdominal vessel; lbw, capillary network of the lateral body wall; ldv, laterodorsal vessel with valve; llv, laterolateral vessel with valve; LOP, direction of blood flow in low‐pressure phase; lv, lateral vessel (heart) with main sphincter; n, capillary network of the nephridium; nv, vessel enclosing dorsal branch of posterior segmental nerve; rbw, capillary network of right body wall; vv, ventral vessel.

Based on
Figure 8. Figure 8.

Diagrams showing blood vessels in the bivalve Anodonta anatina. The ventricle and funnel‐like right atrium are drawn centrally and uppermost in these illustrations. Both (a) and (b) are viewed from right side of the animal with mantle lobe removed. In (a) whole of right ctenidium (branchia) has been removed; in (b) part of the structure is retained to illustrate branchial vessels. Abbreviations: AA, anterior aorta; AB, afferent branchial vessel; AD, anterior adductor artery; EB, efferent branchial vessel; FA, pedal artery; KV, Keber's valve; LP, lateral plexus; MA, mantle artery; MVS, median ventral sinus; PA, posterior artery; PD, posterior adductor artery; PA, pedal sinus; RP, renal plexus; VA, visceral artery.

Both (a) and (b) taken from
Figure 9. Figure 9.

Diagram of superficial arterial and venous vessels in the prosobranch Buccinum. The animal has been removed from its shell and the vascular system injected with pigment. No further dissection is needed to reveal a complex vascular architecture. Consult for descriptions of the deeper vessels. Arrows indicate direction of flow. Abbreviations: Ac, anterior aorta; Af.ct, afferent branchial vessel; Ao, aorta; A.pall, pallial artery; A.ped, pedal artery; BrV., branchial vessels; Dg.g.l, digestive gland; Eff.ct, efferent branchial vessels; Mu.g.l, mucous gland; Op, operculum; Osph, osphradium; Ov, ovary; Ren. eff., vessels of the renal organ; R. Sin., renomucous vessel; Siph, pallial siphon.

From
Figure 10. Figure 10.

Diagram of heart from Littorina, in sagittal section with cut surfaces white. Most of trabecular muscles are omitted. Arrows indicate direction of blood flow; a is during atrial systole, b is during ventricular systole. Abbreviations: A, anterior; aa, anterior aorta; au, atrium; av, aortic valve; avv, atrial‐ventricular valve; ba, bulbus aortae; dch, dorsal channel of atrium; ebv, efferent ctenidial vein; fc, filtration chamber; lm1, longitudinal muscles forming floor of dorsal chamber; lm2, longitudinal muscles controlling reflux of efferent ctenidial vein; nglv, nephridial gland vein; om, occlusor muscle; pa, posterior aorta; pc, pericardial cavity; vdi, distal dorsal chamber of ventricle; vpr, proximal chamber of ventricle.

Taken directly from
Figure 11. Figure 11.

Schematic diagram of circulatory system and systemic heart in Nautilus (lateral view). Head of the animal is located to the left, with chambered shell coiling posteriorly. Arrows show the direction of blood flow. Abbreviations: A, left atrium; ABV/EBV, afferent and efferent branchial vessel; Aod, dorsal aorta; APA, left anterior proventricular artery; APV, anterior pallial vein; BA, buccal artery; CA, cerebral artery; Cp, circulus pallialis; CSA, common septal artery; GA, genital artery; H, ventricle; HCA, hepatico‐columellar artery; MA, inferior mandibular artery; PaA, pallial artery; PeA, pedal artery; PcA, posterior columellar artery; PHA, posterior hood artery; PNA, left pallionuchal artery; PPA, posterior proventricular artery; SA, siphuncular artery; TA, tentacular artery; Vc, cephalic vein. Stippled area is the peripheral sinus, which feeds into cephalic vein.

Drawing taken from
Figure 12. Figure 12.

Schematic diagram of circulatory system in Sepia, viewed from the ventral surface with the mantle sac split and folded over. Head, tentacles, and buccal mass are to the top of the diagram. The general layout in Sepia is similar to other decapods and the octopods. Arrows show direction of blood flow. Abbreviations: ABV/EBV, afferent and efferent branchial vessels; ACV, anterior cephalic vein; AFIV, anterior fin vein; AFUA, anterior funnel artery; AFV, anterior funnel vein; AMA, anterior mantle artery; AMV, anterior mantle vein; AU, atrium; AV, arm vein; BH, branchial heart; BHA, branchial heart appendage; BRA, branchial arteries; CA, cephalic aorta; CV, cephalic veins; GA, gonadial artery; ISV, ink sac vein; OA, ophthalmic artery; OS, optic blood sinus; OV, ophthalmic vein; PAO, posterior aorta; PBS, peribuccal blood sinus; PFUA, posterior funnel artery; PFV, posterior funnel vein; PMV, posterior mantle vein; RVH, ring vein of head; SA, siphuncle artery; TA, tentacle artery; V, ventricle; VC, vena cava.

Drawing taken from
Figure 13. Figure 13.

Examples of the ventricular muscle action potential from the oyster Crassostrea gigas. Figure illustrates form of action potential (prepotential, spike, and plateau) as well as effect of a brief stretch (lower trace in both a and b). Trace 1 is the preceding control interval, trace 2 is the superimposed configuration resulting from stretch application.

Taken directly from
Figure 14. Figure 14.

Diagram of circulatory system of Limulus polyphemus. Dorsal aspect.

Modified from
Figure 15. Figure 15.

Cardiac cycle diagrams. A: Gnathophausia. B: Limulus, C: Haliotus. D: Cancer. Pressures recorded simultaneously at equivalent gain and aligned along a standard pressure axis to show pressure relationships within cardiac cycle in each case. Abbreviations in A.: A, arterial; S, collecting sinus; P, pericardial sinus; H, intracardiac.

Modified from , respectively
Figure 16. Figure 16.

A: Circulatory system of a scorpion. Abbreviations: an, anus; ant.art, anterior aorta; bm, brain; chel, chelicerae; hep.du, hepatic duct; hrt, heart; lat.eye, lateral eye; leg 1–4, legs; mal, malpighian tubules; med. eye, median eye; mesent, mesenteron; ne. co, nerve cord; pect, pectines; pedi, pedipalp; pois.gld, poison gland; post.art, posterior aorta; proct, proctodeum; pul. 1–4, pulmonary sacs; sub.gang, suboesophageal ganglion.

From . B: Circulatory system of a glossiphonid spider. From
Figure 17. Figure 17.

Patterns of cardiac excitation recorded following emergence in Manduca sexta. A. Normoxia. B. Following 10 min normoxic hypercapnia. Top trace is record from impedance electrodes implanted lateral to heart in anterior abdomen. Second trace is impedance record from electrodes positioned 10 mm posterior to the above. Third trace is instantaneous heart rate. Bottom trace is time marked at 30 s intervals.

Previously unpublished data, reproduced with permission from A. Smits
Figure 18. Figure 18.

Heart and circulatory morphology of a range of crustaceans to demonstrate a) increases in complexity of the distribution system and b) condensation of the heart. A: Anostracan. B: Anaspides.

From .] C: Isopod. D: Crab. [From
Figure 19. Figure 19.

Lateral and dorsal views of heart of the crayfish.

From
Figure 20. Figure 20.

A: Changes in cardiac output (A), stroke volume (B), heart rate (C) during hypoxia in lobster and crayfish. B: Changes in arterial flow distribution as a result of hypoxic exposure in crayfish

From
Figure 21. Figure 21.

Effects on heart rate (fH), stroke volume (Vs), and ventricular pulse pressure (Pvent) of increasing afterload on semi‐isolated Carcinus hearts. All ligamentous attachments remained intact. All outflow was restricted to the cannulated sternal artery. Afterload was produced by raising the height of the outflow cannula. All values are normalized.

From
Figure 22. Figure 22.

Blood flow recorded from sternal artery of the lobster Homarus during normoxia (left) and hypoxic exposure (right). Elevated base line in hypoxic indicates that arterial flow is sustained thoughout diastole.

Figure 23. Figure 23.

Microcirculation of the cephalic ganglion in the crayfish Cherax destructor. A: Low‐power view. B: High‐power view showing capillary density. Scale bar = 50 μm.

From , courtesy of Renata Sandeman
Figure 24. Figure 24.

A: Schematic drawing of cardiovascular and nervous systems in Bathynomus. Right and left sides of nervous system have been reversed to facilitate illustration. AA, anterior artery; ACN, anterior cardiac nerve, AG 1–5, abdominal ganglia; AMA, anterior median artery; CA1 and CA2, first and second cardioaccelerator nerves; LA1–5, first to fifth lateral arteries; LCN, lateral cardiac nerves 1–5; r and l ALA, right and left anterior lateral arteries; TG 4–8, thoracic ganglia. B: Simultaneous records of efferent impulses in LCN 5 and swimmeret movements. Dots show end of return stroke, a: swimmerets spontaneously active. b: swimmerets activated by water jet stimulation of oral area.

From
Figure 25. Figure 25.

Distribution of flow in arterial systems of the lobster Homarus. A: Effects of proctolin. B: Effects of a sudden startling stimulus.

Figure 26. Figure 26.

Survey of the effects of neurotransmitters (acetylcholine and glutamic acid and hormones (5‐hydroxytryptamine, dopamine, CCAP, proctolin, F1, and F2) on arterial resistance in Homarus. Arteries were perfused at 2 ml · min−1. Concentration of each drug was the same in each graph. Concentration used for each drug is shown beneath the lower left figure (‐3 = 10−3M, etc.) Abbreviations: AMA, anterior aorta; ALA, anterior lateral artery; HA, hepatic artery; SA, sternal artery; DAA, posterior aorta.

J. L. Wilkens, unpublished observations
Figure 27. Figure 27.

Interaction between hemal system, alimentary canal, and respiratory trees (ventilatory system) in the sea cucumber, hostichopus badionotus. A: Overall view. B and C: Details of circulatory interactions with the intestine (B) and with the respiratory trees (C). Abbreviations: e, esophagus; g, gut; s, stomach; i, intestine; il, intestinal lamellae; h, “hearts”; ibv, vessels of intestinal lamellae; dv, primary dorsal vessel; vv, primary ventral vessel; dtv, dorsal transverse vessel; pv, pulmonary vessel, rt, respiratory tree; vp, vascular plexus associated with respiratory trees; asi/dsi, ascending and descending small intestine; li, large intestine (avascular). Arrows indicate direction of flow.

From , modified from
Figure 28. Figure 28.

A: Stereogram of structure of front end of the body of the pogonophoran Oligbrachia dogleili in ventral view. Abbreviations: ad, anastomosing end of the coelomoducts; cex, distal end of coelomoducts; cin, proximal canal of coelomoduct; coe, coelomic canal of tentacle; coel, protocoel; coe ll, mesocoel; cor, heart; ex, excretory portion of coelomoduct; mdv, dorso‐ventral muscles; pc, external pore of coelomoduct; pr, pericardial sac; t, tentacle; va, afferent tentacular vessel; vd, dorsal vessel; ve, efferent tentacular vessel; vl, lateral cephalic vessel; vm, median cephalic vessel; vv, ventral vessel.

From .] B: Diagram of the anterior circulatory system of Lamellibrachia, Arrows show direction of flow. Abbreviations: dv, dorsal vessel; h, heart; ov, obturacular vessels; rv/lv, right and left vessels of vestimental region; sv, sinus valvatus; tv, origin of tentacular vessels; vv, ventral vessel. [Modified from .] C: Diagrams comparing the arrangement of afferent tentacular blood supply in (i) Lamellibrachia and (ii) Riftia. Abbreviations: bdv, branching dorsal vessel; dv, dorsal vessel; tv, tentacular vessels. [Modified from


Figure 1.

Path of extracellular fluid movement through simplest internal circulatory systems, digenean trematode flatworm Cotylophoron.

Modified from


Figure 2.

Range of circulatory systems seen in nemertean worms A: Cephalothrix. B: Tubulanus.

From


Figure 3.

A: Drawing of blood vascular system of a polychaete annelid worm Amphitrite. Abbreviations: abv, afferent branchial vessels; as, anterior stomach; d, diaphragm; drv, dorsal ring vessels; ds, diaphragm sac; dv, dorsal vessel; e, esophagus; elor, efferent bronchial vessel; g, gills; gs, gut sinus; h, heart; i, intestine; lm, longitudinal muscles; Iv, lateral vessel; n, nephridium; ph, pharynx; pi, posterior intestine; pr, prostomium; ps, posterior stomach; s, septa; srv, segmental ring vessel; sv, subintestinal vessels; vg, ventral glands; vrv, ventral ring vessels B: Drawing to show segmental organization of the blood system in an errant polychaete. Abbreviations; dbv, dorsal blood vessel; i, intestine; lm, longitudinal muscle; pv parapodial vessels; vnc, ventral nerve cord; vbv, ventral blood vessel. The elaborate circulatory supply in the parapodium is for gas exchange.

From


Figure 4.

A: Sections of the vascular and coelomic sinus systems of the Hirudinea (leeches). In the “primitive” leech, Placobdella costata, the dorsal and ventral coelomic sinuses (ds, dorsal sinus; vs, ventral sinus) surround the much reduced dorsal and ventral vessels (dv and vv, respectively). Other labeled structures: is, intermediate sinus; ls, lateral sinus (= LH); nc, ventral nerve cord; vs, ventral sinus. B: Coelomic sinus system of the leech Hirudo medicinalis, in which all traces of the original dorsal and ventral vessels are lost. Abbreviations: lds, laterodorsal sinus; lls, laterolateral sinus; lvs, lateroventral sinus; nc, nerve cord; sl, subepidermal lacunae; t, testis.

From


Figure 5.

Structure and innervation in lateral hearts of the leech Hirudo. A: Regional differentiation in cardiac myocytes of leech lateral heart. Structure of two muscle cells pressure injected with Lucifer yellow. The cell on left is in trans form, while one on right is in cis form. Scale bar 50 μm.

From .] B: Reconstruction of cis‐configuration muscle cell after cobalt staining and sectioning, showing its orientation along axis of lateral heart [From .] C: Location of sphincter valves in one midbody segment of a lateral vessel (posterior to region called heart) wall of the leech Hirudo with rostral end opened dorsally. Abbreviations: c, caudal; las, lateral abdominal sphincter; lav, lateral abdominal vessel; ldv, lateral dorsal vessel; llv, latero‐lateral vessel; lv, lateral vessel (heart); r, rostral; s, main sphincter; v, valve. Arrows indicate direction of flow. [From


Figure 6.

A: Schematic drawing of relationship between ventral nerve cord and lateral hearts of H. medicinalis.

From .] B: Example of entrainment of myogenic rhythm of leech lateral heart muscle by HE motor neuron bursts. The heart rhythm is normally phase‐locked with HE cell activity rhythm. When HE cell was hyperpolarized, lateral heart muscle innervated by this neuron continued to beat rhythmically, but at slightly slower rate. After about 40 s of hyperpolarization, antidromically conducted action potentials appeared in HE cell as peripheral neurogenic rhythm began to be expressed (open arrows). At the solid arrow a relatively strong neurogenic burst reset myogenic rhythm. When HE cell was released from hyperpolarization it again entrained the muscle to its own rhythm. Solid dots indicate expected time of myogenic bursts. Open dots indicate actual time bursts entrained by HE cell. CM, current monitor; HE, heat excitation motoneuron; L, 4, location of recording electrode; nA, nanno‐amps; left = 4th ganglion. [From


Figure 7.

Scheme of the circulatory system of the leech H. medicinalis. A: Six fused anterior segments. B: Scheme valid for the 21 somatic segments. C: Scheme valid for segments that contain the intestine. D: Seven fused posterior segments. Abbreviations: ci, capillary network of intestine; dbw, capillary segments of dorsal body wall; dv, dorsal vessel; HIP, direction of blood flow in high‐pressure phase; iv, lateral intestinal vessel; lav, lateral abdominal vessel; lbw, capillary network of the lateral body wall; ldv, laterodorsal vessel with valve; llv, laterolateral vessel with valve; LOP, direction of blood flow in low‐pressure phase; lv, lateral vessel (heart) with main sphincter; n, capillary network of the nephridium; nv, vessel enclosing dorsal branch of posterior segmental nerve; rbw, capillary network of right body wall; vv, ventral vessel.

Based on


Figure 8.

Diagrams showing blood vessels in the bivalve Anodonta anatina. The ventricle and funnel‐like right atrium are drawn centrally and uppermost in these illustrations. Both (a) and (b) are viewed from right side of the animal with mantle lobe removed. In (a) whole of right ctenidium (branchia) has been removed; in (b) part of the structure is retained to illustrate branchial vessels. Abbreviations: AA, anterior aorta; AB, afferent branchial vessel; AD, anterior adductor artery; EB, efferent branchial vessel; FA, pedal artery; KV, Keber's valve; LP, lateral plexus; MA, mantle artery; MVS, median ventral sinus; PA, posterior artery; PD, posterior adductor artery; PA, pedal sinus; RP, renal plexus; VA, visceral artery.

Both (a) and (b) taken from


Figure 9.

Diagram of superficial arterial and venous vessels in the prosobranch Buccinum. The animal has been removed from its shell and the vascular system injected with pigment. No further dissection is needed to reveal a complex vascular architecture. Consult for descriptions of the deeper vessels. Arrows indicate direction of flow. Abbreviations: Ac, anterior aorta; Af.ct, afferent branchial vessel; Ao, aorta; A.pall, pallial artery; A.ped, pedal artery; BrV., branchial vessels; Dg.g.l, digestive gland; Eff.ct, efferent branchial vessels; Mu.g.l, mucous gland; Op, operculum; Osph, osphradium; Ov, ovary; Ren. eff., vessels of the renal organ; R. Sin., renomucous vessel; Siph, pallial siphon.

From


Figure 10.

Diagram of heart from Littorina, in sagittal section with cut surfaces white. Most of trabecular muscles are omitted. Arrows indicate direction of blood flow; a is during atrial systole, b is during ventricular systole. Abbreviations: A, anterior; aa, anterior aorta; au, atrium; av, aortic valve; avv, atrial‐ventricular valve; ba, bulbus aortae; dch, dorsal channel of atrium; ebv, efferent ctenidial vein; fc, filtration chamber; lm1, longitudinal muscles forming floor of dorsal chamber; lm2, longitudinal muscles controlling reflux of efferent ctenidial vein; nglv, nephridial gland vein; om, occlusor muscle; pa, posterior aorta; pc, pericardial cavity; vdi, distal dorsal chamber of ventricle; vpr, proximal chamber of ventricle.

Taken directly from


Figure 11.

Schematic diagram of circulatory system and systemic heart in Nautilus (lateral view). Head of the animal is located to the left, with chambered shell coiling posteriorly. Arrows show the direction of blood flow. Abbreviations: A, left atrium; ABV/EBV, afferent and efferent branchial vessel; Aod, dorsal aorta; APA, left anterior proventricular artery; APV, anterior pallial vein; BA, buccal artery; CA, cerebral artery; Cp, circulus pallialis; CSA, common septal artery; GA, genital artery; H, ventricle; HCA, hepatico‐columellar artery; MA, inferior mandibular artery; PaA, pallial artery; PeA, pedal artery; PcA, posterior columellar artery; PHA, posterior hood artery; PNA, left pallionuchal artery; PPA, posterior proventricular artery; SA, siphuncular artery; TA, tentacular artery; Vc, cephalic vein. Stippled area is the peripheral sinus, which feeds into cephalic vein.

Drawing taken from


Figure 12.

Schematic diagram of circulatory system in Sepia, viewed from the ventral surface with the mantle sac split and folded over. Head, tentacles, and buccal mass are to the top of the diagram. The general layout in Sepia is similar to other decapods and the octopods. Arrows show direction of blood flow. Abbreviations: ABV/EBV, afferent and efferent branchial vessels; ACV, anterior cephalic vein; AFIV, anterior fin vein; AFUA, anterior funnel artery; AFV, anterior funnel vein; AMA, anterior mantle artery; AMV, anterior mantle vein; AU, atrium; AV, arm vein; BH, branchial heart; BHA, branchial heart appendage; BRA, branchial arteries; CA, cephalic aorta; CV, cephalic veins; GA, gonadial artery; ISV, ink sac vein; OA, ophthalmic artery; OS, optic blood sinus; OV, ophthalmic vein; PAO, posterior aorta; PBS, peribuccal blood sinus; PFUA, posterior funnel artery; PFV, posterior funnel vein; PMV, posterior mantle vein; RVH, ring vein of head; SA, siphuncle artery; TA, tentacle artery; V, ventricle; VC, vena cava.

Drawing taken from


Figure 13.

Examples of the ventricular muscle action potential from the oyster Crassostrea gigas. Figure illustrates form of action potential (prepotential, spike, and plateau) as well as effect of a brief stretch (lower trace in both a and b). Trace 1 is the preceding control interval, trace 2 is the superimposed configuration resulting from stretch application.

Taken directly from


Figure 14.

Diagram of circulatory system of Limulus polyphemus. Dorsal aspect.

Modified from


Figure 15.

Cardiac cycle diagrams. A: Gnathophausia. B: Limulus, C: Haliotus. D: Cancer. Pressures recorded simultaneously at equivalent gain and aligned along a standard pressure axis to show pressure relationships within cardiac cycle in each case. Abbreviations in A.: A, arterial; S, collecting sinus; P, pericardial sinus; H, intracardiac.

Modified from , respectively


Figure 16.

A: Circulatory system of a scorpion. Abbreviations: an, anus; ant.art, anterior aorta; bm, brain; chel, chelicerae; hep.du, hepatic duct; hrt, heart; lat.eye, lateral eye; leg 1–4, legs; mal, malpighian tubules; med. eye, median eye; mesent, mesenteron; ne. co, nerve cord; pect, pectines; pedi, pedipalp; pois.gld, poison gland; post.art, posterior aorta; proct, proctodeum; pul. 1–4, pulmonary sacs; sub.gang, suboesophageal ganglion.

From . B: Circulatory system of a glossiphonid spider. From


Figure 17.

Patterns of cardiac excitation recorded following emergence in Manduca sexta. A. Normoxia. B. Following 10 min normoxic hypercapnia. Top trace is record from impedance electrodes implanted lateral to heart in anterior abdomen. Second trace is impedance record from electrodes positioned 10 mm posterior to the above. Third trace is instantaneous heart rate. Bottom trace is time marked at 30 s intervals.

Previously unpublished data, reproduced with permission from A. Smits


Figure 18.

Heart and circulatory morphology of a range of crustaceans to demonstrate a) increases in complexity of the distribution system and b) condensation of the heart. A: Anostracan. B: Anaspides.

From .] C: Isopod. D: Crab. [From


Figure 19.

Lateral and dorsal views of heart of the crayfish.

From


Figure 20.

A: Changes in cardiac output (A), stroke volume (B), heart rate (C) during hypoxia in lobster and crayfish. B: Changes in arterial flow distribution as a result of hypoxic exposure in crayfish

From


Figure 21.

Effects on heart rate (fH), stroke volume (Vs), and ventricular pulse pressure (Pvent) of increasing afterload on semi‐isolated Carcinus hearts. All ligamentous attachments remained intact. All outflow was restricted to the cannulated sternal artery. Afterload was produced by raising the height of the outflow cannula. All values are normalized.

From


Figure 22.

Blood flow recorded from sternal artery of the lobster Homarus during normoxia (left) and hypoxic exposure (right). Elevated base line in hypoxic indicates that arterial flow is sustained thoughout diastole.



Figure 23.

Microcirculation of the cephalic ganglion in the crayfish Cherax destructor. A: Low‐power view. B: High‐power view showing capillary density. Scale bar = 50 μm.

From , courtesy of Renata Sandeman


Figure 24.

A: Schematic drawing of cardiovascular and nervous systems in Bathynomus. Right and left sides of nervous system have been reversed to facilitate illustration. AA, anterior artery; ACN, anterior cardiac nerve, AG 1–5, abdominal ganglia; AMA, anterior median artery; CA1 and CA2, first and second cardioaccelerator nerves; LA1–5, first to fifth lateral arteries; LCN, lateral cardiac nerves 1–5; r and l ALA, right and left anterior lateral arteries; TG 4–8, thoracic ganglia. B: Simultaneous records of efferent impulses in LCN 5 and swimmeret movements. Dots show end of return stroke, a: swimmerets spontaneously active. b: swimmerets activated by water jet stimulation of oral area.

From


Figure 25.

Distribution of flow in arterial systems of the lobster Homarus. A: Effects of proctolin. B: Effects of a sudden startling stimulus.



Figure 26.

Survey of the effects of neurotransmitters (acetylcholine and glutamic acid and hormones (5‐hydroxytryptamine, dopamine, CCAP, proctolin, F1, and F2) on arterial resistance in Homarus. Arteries were perfused at 2 ml · min−1. Concentration of each drug was the same in each graph. Concentration used for each drug is shown beneath the lower left figure (‐3 = 10−3M, etc.) Abbreviations: AMA, anterior aorta; ALA, anterior lateral artery; HA, hepatic artery; SA, sternal artery; DAA, posterior aorta.

J. L. Wilkens, unpublished observations


Figure 27.

Interaction between hemal system, alimentary canal, and respiratory trees (ventilatory system) in the sea cucumber, hostichopus badionotus. A: Overall view. B and C: Details of circulatory interactions with the intestine (B) and with the respiratory trees (C). Abbreviations: e, esophagus; g, gut; s, stomach; i, intestine; il, intestinal lamellae; h, “hearts”; ibv, vessels of intestinal lamellae; dv, primary dorsal vessel; vv, primary ventral vessel; dtv, dorsal transverse vessel; pv, pulmonary vessel, rt, respiratory tree; vp, vascular plexus associated with respiratory trees; asi/dsi, ascending and descending small intestine; li, large intestine (avascular). Arrows indicate direction of flow.

From , modified from


Figure 28.

A: Stereogram of structure of front end of the body of the pogonophoran Oligbrachia dogleili in ventral view. Abbreviations: ad, anastomosing end of the coelomoducts; cex, distal end of coelomoducts; cin, proximal canal of coelomoduct; coe, coelomic canal of tentacle; coel, protocoel; coe ll, mesocoel; cor, heart; ex, excretory portion of coelomoduct; mdv, dorso‐ventral muscles; pc, external pore of coelomoduct; pr, pericardial sac; t, tentacle; va, afferent tentacular vessel; vd, dorsal vessel; ve, efferent tentacular vessel; vl, lateral cephalic vessel; vm, median cephalic vessel; vv, ventral vessel.

From .] B: Diagram of the anterior circulatory system of Lamellibrachia, Arrows show direction of flow. Abbreviations: dv, dorsal vessel; h, heart; ov, obturacular vessels; rv/lv, right and left vessels of vestimental region; sv, sinus valvatus; tv, origin of tentacular vessels; vv, ventral vessel. [Modified from .] C: Diagrams comparing the arrangement of afferent tentacular blood supply in (i) Lamellibrachia and (ii) Riftia. Abbreviations: bdv, branching dorsal vessel; dv, dorsal vessel; tv, tentacular vessels. [Modified from
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Brian R. McMahon, Jerrel L. Wilkens, Peter J. S. Smith. Invertebrate Circulatory Systems. Compr Physiol 2011, Supplement 30: Handbook of Physiology, Comparative Physiology: 931-1008. First published in print 1997. doi: 10.1002/cphy.cp130213