FAU Institutional Repository http://purl.fcla.edu/fau/fauir This paper was submitted by the faculty of FAU’s Harbor Branch Oceanographic Institute. Notice: ©1981 The Ichthyological Society of Japan. This article may be cited as: Mok, H.-K. (1981). The posterior cardinal veins and kidneys of fishes, with notes on their phylogenetic significance. Japanese Journal of Ichthyology, 27(4), 281-290. =tr fl71 Japanese Journal of Ichthyology Vol. 27, No.4 1981 The Posterior Cardinal Veins and Kidneys of Fishes, with Notes on Their Phylogenetic Significance Hin-Kiu Mok (Received November 27, 1979) Abstract The variations of the relation and relative size of the posterior cardinal veins and the fusion of the left and right kidneys in seme major fish groups are described. The morphological variations of these characters in the two systems are interpreted and hypotheses concerning the phylogenetic interrelationships of the fish groups are made. The neoposterior cardinal veins being equally long is treated as a plesiomorphic character state for actinopterygians. In the vast majority of these fishes the right neoposterior cardinal vein is much longer and larger in diameter than the left one. The left neoposterior cardinal vein of osteoglossomorphs (including hiodontids) is larger and longer than the right. This synapomorphic character state supports their monophyletic relationships. The presence of a connection between the hepatic and neoposterior cardinal vein in brachiopterygians suggests' their affinity with other sarcopterygians. The presence of an anterior median sinus in chondrichthyans formed by the fused parts of the anterior neoposterior cardinal veins may be synapornorphic for gnathostomes and indicates the monophyly of chondrichthyans. Complete separation of the left and right kidneys which is here hypothesized as an apo­ morphic character state of the gnathostome kidney morphology has appeared at least three times in this fish group. This character state casts light on the monophyly of Brachio­ pterygii, Dipnoi, and Tetrapoda. Occurrence ofsimilar character states in other gnathostomes is due to convergence. While conducting a survey of gnathostome After the removal of these organs, the kidney kidney morphology, I noticed some morpho­ could be easily observed. The posterior car­ logical variations in the posterior cardinal vein dinal veins are embedded on the surface of system and the fusion of the left and right the left and right kidneys. The shape of the kidneys (Mok, 1978). The phylogenetic signifi­ kidney, the size, length, and relation of the cance of these diversities have not been suf­ left and right posterior cardinal veins were ficiently exploited. Therefore, I undertook a recorded. preliminary review of these two systems with Specimens examined: Chimaeridae: Chi­ special attention to the application of these maera phantasma, AMNH uncat., 150 mm TL morphological variations to reconstruct the (total length). Dasyatidae: Taeniura meyeni, phylogenetic history of gnathostomes. AMNH uncat., 150 mm TL. Squalidae: Squa­ Ius acanthias, AMNH 1023, 160 mm TL. Lati­ Materials and methods meriidae: Latimeria chalumnae, AMNH 36941, The specimens examined in the present 1300 mm TL. Lepidosirenidae: Lepidosiren study are from the Ichthyology Department, paradoxa, GD 7.068.1, 540mm TL. Polypter­ American Museum of Natural History idae: Calamoichthys calabaricus, AMNH un­ (AMNH); personal collections of Dr. Peter cat., 190 mrn, 240 mm TL; Polypterus ornati­ Moller (PM) of the City University of New pinnis, AMNH 6349, 108 mm TL; Polypterus York, and Mr. Guido Dingerkus (GD) of the palmas, AMNH 6300, 110 mm, 114 mm TL. Ichthyology Department, American Museum Acipenseridae: Acipenser stellatus, AMNH of Natural History. One or more individuals 20694, 157 mm TL. Polyodontidae: Polyodon of each species studied were examined. The spathula, AMNH uncat., 288mm TL. Lepiso­ viscera including the gastrointestinal tract and steidae: Lepisosteus oculatus, AMNH 37370, the swimbladder (if present) were removed. 148 mm TL; Lepisosteus platyrhincus, AMNH -281- Japan. J. Ichthyol. 27(4), 1981 27734, 237 mm TL. Amiidae: Amia calva, "We have no evidece to show whether this AMNH uncat., 107 mm TL. Osteoglossidae: single interrenal posterior cardinal vein in Osteoglossum bicirrhosum, AMNH uncat., 75 Squalus is formed by the fusion of the two mm, 80 mm SL (standard length). Pantodon­ limbs of the loop (loop of Jacobson), or tidae: Pantodon buchholzi, AMNH uncat., whether only one of them persists, as for 75 mm SL. Hiodontidae: Hiodon alosoides, example in Mustelus antarcticus and Noto­ AMNH 23754, 60 mm, 67 mm SL. Notopteri­ rhynchus maculatus." dae: Notopterus sp., AMNH uncat., 150 mm, Besides the posterior fusion of neoposterior 160 mm SL; Xenomystus nigri, AMNH uncat., cardinal veins, a spacious medial sinus may 150 mm, 160 mm SL. Gymarchidae: Gymnar­ be frequetly formed by the fused anterior chus niloticus, PM uncat., 312 mm TL. Mormy­ portion of the neoposterior cardinal veins in ridae: Gnathonemus sp., AMNH 19671, 110 chondrichthyans, such as Squalus acanthias, mm TL; Mormyrops deliciosus, AMNH 6892, S. sucklii, Scyllium canicula (O'Donoghue, 142 mm SL; Petrocephalus sp., AMNH 6885, 1914; O'Donoghue and Abbott, 1928: fig. lB), 84 mm SL. Anguillidae: Anguilla rostrata, Raja nasuta (Parker, 1881), and Hydrolagus AMNH 36091, 283 mm TL. colliei (Stahl, 1967). This anterior sinus is insignificant in Mustelus antarcticus (Parker, Results 1886: pI. 34). The time of its appearance is Posterior cardinal vein system. The pos­ variable. It develops in late embryonic stages terior cardinal vein system of primitive gnatho­ in Scyllium canicula (O'Donoghue and Abbott, stomes consists of (I) the paired renal portal 1928), but does not appear until maturation veins representing the posterior part of the in Squalus (Walker, 1956). protoposterior cardinal veins, present in chon­ There are resemblances between the posterior drichthyan embryonic stage and in adult cycle­ cardinal vein system of holocephalian fish stomes (see below), (2) the medial unpaired (Hydrolagus colliei) and the elasmobranchs. caudal vein joining the renal portal vein at In the former, there are numerous, sizable its anterior end, and (3) the paired neoposterior communications between the left and right cardinal vein which is a composite of the neoposterior cardinal veins, and posteriorly at subcardinal vein and the anterior section of the origin of the trunk between the kidneys, the protoposterior cardinal vein (Smith, 1960). there is a single median vein, the interrenal In elasmobranchs such as Squalus, a con­ vein (Stahl, 1967). Stahl made no mention nection between the anterior section of the of the composition of the interrenal vein. protoposterior cardinal vein and the subcar­ There are some generalized characters of dinal vein on each side is formed early in the chondrichthyan posterior cardinal vein ontogeny (Walker, 1956: fig. lA). The left system: (I) the left and right neoposterior and right subcardinal veins communicate cardinal veins are recognizable and equal in medially by some short cross anastomoses at length; (2) the posterior parts of these veins their posterior sections and have no connec­ are connected by anastomoses; (3) a median tion to the posterior sections of the proto­ anterior sinus is present; (4) the extreme an­ posterior cardinal veins. These anastomoses terior sections of these veins (or the neo­ may be absent in the adult, e.g., Squalus posterior cardinal sinuses) tend to increase in acanthias, S. sucklii (O'Donoghue and Abbott, diameter. The primitive nature of the first 1928), and Scyllium canicula (O'Donoghue, character state is indicated by the presence of 1914). A medial interrenal vein is present neoposterior cardinal veins of equal length in posteriorly in S. canicula (O'Douoghue and both embryonic and adult stages of some Abbott, 1928: fig. IB). This vein is com­ elasmobranchs (e.g., Walker, 1956). Reduction posed of the fused posterior (or the subcardinal) in length of either one of these veins, or sections of the neoposterior cardinals or of longitudinal fusion of their posterior sections, one of these veins when the other has lost has also been observed in chondrichthyans. its posterior section. O'Donoghue and Abbott The left neoposterior cardinal vein is shortened (1928 : 873) wrote about the interrenal vein, in Mustelus antarcticus; the short left neo- -282- Mok : Posterior Cardinal Veins and Kidneys apC'V ,- h eev ./ hv npev sv ms ppcv an rpv iv ev A B Fig. I. Simplified diagram of the posterior cardinal vein system in (A) Squalus sp. (late embryonic stage; after Walker , 1956) and (B) Scyllium canicula (after O'Donoghue and Abbott, 1928). an, anastmosis; apcv, anterior protoposterior cardinal vein; ccv, common cardinal vein; cv, caudal vein; h, heart; hv, hepatic vein; iv, interrenal vein; ms, medial sinus of the fused neoposterior cardinal veins; npcv, neoposterior cardinal vein; ppcv, posterior protoposterior cardinal vein; rpv, renal portal vein; sv, subcardinal vein. posterior cardinal vein has short transverse protopostcava which exists in all living tetra­ anastomoses joining the long right one, which pods (except mammals), dipnoans, polypterids, is also larger in diameter (Parker, 1886). and coelacanths (also see below), the sub­ Burne (1923: 246) observed a reduction in cardinal (or the posterior) portions of the neo­ neoposterior cardinal length in Lamna nasus posterior cardinal veins tend to fuse medially and wrote, "It is clear that