New Species of Acanthobothrium (Cestoda: Tetraphyllidea) from ...

New Species of Acanthobothrium (Cestoda: Tetraphyllidea) from ...

CAMPBELL-NEW SPECIES OF ACANTHOBOTHRIUM FROM CHESAPEAKE BAY 561TABLEI. Descriptions concerning Acanthobothrium paulum from earlier literature. Figures in thetable reproduced from descriptions by authors listed in the heading.Author Linton Southwell Baer BaerDate 1890 1925 1948 1948Description original redescription redescription redescriptionSpecies A. paulum A. benedeni A. paulum A. woodsholeiSynonym A. paulum A. coronafumLinton, 1890sensu Linton,( 1901)Type host D. cenfroura D. centroura D. centroura D. centroura Total length 4.5-20 mm 5-19 mm 11 mm 12-15 mm Width (between) 180-260 p 320 p -120-260 sNo. segments (small worms )16-20 Scolex length600 p Scolex width260-420 s Bothridial length500-800 p Bothridial width120-240 p Anterior loculus -Middle loculus Posterior loculus Accessory sucker diameter Hook handle Inner pronglength of a single prong,Outer prong 100-140 s 108-144 p 81 pTotal hook length 140-200 p 216 p 129 pPeduncle length 0.7-1.4 mm 1.6 inm shortPeduncle width 80-240 p 320 pTestes diameter about 30 p - 50 PTestes per segment - 40-45 50-55Postvaginally 7 (figure) 5 (figure)Prevaginally 11 (figure) 15 (figure)Antiporally 23 (figure) 32 (figure)Mature segment length 0.68-1.6 mm 2 mm 640 phlatnre segment width 180-260 p - 320 p 480 sGenital pore near middle midmarginal towards middle postequatorialCirms pouch length 207 p 252 pCirrus pouch width 92-115 p 108 pCirrus pouch extent -Cirrus length -Cirrus spine length: base tip Ovarian lobe widthAporal lobe lengthPoral lobe lengthVitelline acini 75 P 690 p 660 p; reaching cirrus pouch vaginal testes (6 womls, 30 segments), 20 f 2 Host: Dasyatis americana Hildebrand and(18 to 25); prevaginal testes (6 worms, 30 seg- Schroeder, southern stingray.ments), 12 f 2 (9 to 14); antiporal testes (6 Locality: Chesapeake Bay, Virginia.worms, 30 segments), 40 & 3 (36 to 44). Ovarian Holotype and paratype: USNM Helm. Coll.,lobes unequal; poral lobe reaching cirrus pouch in Nos. 71355 and 71356.mature and gravid segments; 88 to 286 long by41 to 108 wide in mature segments; aporal lobe Remarks109 to 338 long by 52 to 88 wide, extending toHook measurements and morphology, testesmedian level of cirrus pouch; ovarian lobes up totwice as long in gravid segments; isthmus of ovary number, and testes distribution serve to dislongand narrow, about 156 to 260 in length. tinguish this species from other members of theVitelline acini about 42 (31 to 52) in diameter. genus parasitizing skates and rays. Of the spe-Ventral osmoregulatory canal very large; diameter cies of Acanthobothrium known from Americanabout 97 to 127 in mature segments; dorsal osmoregulatorycanal 10 to 20 in diameter, may appearwaters, A. americanum most closely resemblesto be absent if collapsed.A. tortum (Linton, 1916) but differs markedly

562 THE JOURNAL OF PARASITOLOGY, VOL. 55, NO. 3, JUNE 1969FIGURES 7-9. Acanthobothrium, cont'd. 7. A. americanum, gravid segment. 8. A. paulum, maturesegment. 9. A. americanum, mature segment.from the latter in number (90) and distributionof testes (21 prevaginally), hook morphology,total hook length (275 to 300), cirruspouch measurements (338 by 250), and mor-phology of the ovary, as well as in the familyof elasmobranchs (Myliobatidae) serving asits host. Comparison was made with specimensof A. tortum from the type host donated

CAMPBELL-NEW SPECIES OF ACANTHOBOTHRIUM FROM CHESAPEAKE BAY 563by Dr. R. J. Goldstein. Redescription of A.tortum will be presented elsewhere.Acanthobothrium americanrim also resemblesA. zschokkei Baer, 1948, from the MediterraneanSea, but may be differentiated fromthis species by the aforementioned charactersas well as by bothridial dimensions (500 to700 by 200 to 350), and cirrus length (1.5to 1.7 mm).Acanthobothrium brevissime Linton, 1908syn. A. duiardini sensu Southwell (1925)(Figs. 1 1, 14, 15, 19)DescriptionAcraspedote, apolytic. Length ( 25 worms), 3.5mm ( 1.5 to 4.2); width (25 worms), 157 ( 110 to200). Number of segments (25 worms), 16 (7 to29). Scolex length (25 worms), 371 (320 to 475);width (25 worms), 253 ( 183 to 300). One accessorysucker per bothridium; diameter of accessorysucker (25 worms, 90 suckers), 31 + 3 (24 to41). Bothridial length (25 worms, 86 bothridia ),307 & 15 (260 to 360); width (25 worms, 82bothridia ), 121 ( 104 to 150); anterior locul~is (25worms, 81 loculi ), 138 ( 88 to 208) ; middle loc~ilus(25 worms, 84 loculi), 65 (41 to 80); posteriorlocul~is (25 worms, 85 loculi), 52 (25 to 79).Hook handle (20 worms, 120 handles), 30 + 3(24 to 37); inner prong longer than outer prong;inner prong (20 worms, 102 prongs), 79 ? 12(66 to 115); outer prong (20 worms, 93 prongs),67 & 10 (52 to 96); total hook length (20 worms,104 hooks), 115 -+ 11 (96 to 151). Peduncle (25worms), 253 ( 120 to 432) long, spinose; width (20worms), 84 (70 to 108). Mature segment length(9 worms, 18 segments), 683 (254 to 1 nun);width (9 worms, 18 segments), 175 (140 to 310).Cirrus pouch variable in shape, triangular to spherical,extending more than W segment width in maturesegments; length (8 worms, 19 pouches), 93(66 to 127); width (8 worms, 19 pouches), 89(66 to 130). Cirrus armed; cirrus spine length,5 at base, 10 at bulbous swelling, 3 at tip. Genitalpores midmarginal to preequatorial; irregularly alternating.Testes spherical, 42 to 50 in diameter;testes per segment (23 worms, 143 segments), 28? 4 (19 to 40); postvaginal testes (23 worms, 143segments), 3 & 1 (2 to 5); prevaginal testes (23worms, 143 segments), 9 * 2 (6 to 14); antiporaltestes (23 worms, 143 segments), 15 + 3 (11to 22). Ovarian lobes variable in extent, equalor unequal; poral lobe 108 to 400 long by 40wide; aporal lobe 97 to 432 long by 40 wide.Vitelline acini 15 to 25 in diameter. Seminal receptacleand vaginal sphincter present. Ventralosmoregulatory canal about twice the diameter ofdorsal osmoregulatory canal.Hosts: Dusyatis sabina ( LeSueur ), round stingray;D. sayi (LeSueur), Say's stingray; new hosts:D. americana Hildebrand and Schroeder, southernstingray; Raja eglanteria Bosc, clear-nosed skate.Loculity: Gulf of Mexico and Chesapeake Bay,Virginia.RemarksDue to the fragmented condition of Linton'stype material, Goldstein (1964) redescribedthis species and designated a neotype. However,appraisal of this redescription revealsdiscrepancies in the following: ( 1) measurementsfor bothridial width which should havebeen 116 (96 to 138) (pers. comm., R. J.Goldstein) instead of 155 (75 to 138); (2) theneotype was the one specimen that most resembledLinton's type material but typicalspecimens do not resemble the neotype; and(3) redescription was made from a small sampleof material. Comparison of specimens fromDr. Goldstein's collection have shown his specimensto closely resemble mine. Apparently,Linton (1908) recovered a few smaller worms,which he described, and never encounteredlarger individuals. Of the numerous individualsof this species I have recovered, the majoritywere larger than the form he described. Therefore,I have redescribed this species from alarger number of worms and deposited specimenstypical of both Dr. Goldstein's collectionand my own in the USNM Helm. Coll. Redescriptionis based on worms recovered fromD. americana which were found to be indistinguishablefrom those recovered from R.eglanteria. Specimens from both R. eglanteriaand D. americana have been deposited in theUSNM Helm. Coll., Nos. 71349 and 71350.Acanthobothrium brevissime has been comparedwith Acanthobothrium benedeni Loennberg,1889, from Raja clavata L. from theMediterranean Sea, which it most closely resembles,and I have found these two speciesto be distinct. Acanthobothrium brevissimemay be differentiated from A. benedeni onthe basis of total hook length (go), cirruspouch dimensions (140 by 120), and generalmorphology. Acanthobothrium benedeni willbe redescribed elsewhere.Accmthobothrium floridensis Goldstein, 1964Host: Raja eglanteria Bosc, clear-nosed skate.Locality: Gulf of Mexico and Chesapeake Bay,Virginia.RemarksOf 10 mature specimens of A, floridensisexamined, most characters agree closely withthose given by Goldstein, 1964. However, it


566 THE JOURNAL OF PARASITOLOGY, VOL. 55, NO. 3. JUNE 1969FIGURES 16-20. Acanthobothritcm, cont'd. 16. A, lineatum, mature segment. 17. A. americanum,cross section through isthmus of ovary. 18. A. paulum, egg. 19. A. brevissime, mature segment. 20.A. paulum, detail of ootype ( gravid segment).

CAMPBELL-NEW SPECIES OF ACANTHOBOTHRIUM FROM CHESAPEAKE BAY 567147 (80 to 240); posterior loculus (25 worms, 65loculi), 130 ( 80 to 200 ). Hook handle ( 37 worms,130 handles ), 35 t 7 (22 to 57); inner prong ( 37worms, 135 prongs), 110 & 13 (75 to 171 ); outerprong (37 worms, 129 prongs), 93 t 14 (53 to157); total hook length (37 worms, 120 hooks),152 e 18 ( 104 to 229). Peduncle very variable,usually contracted (30 worms), 844 (400 to 1.5mm) long; spinose; width (30 worms), 199 ( 120to 300). Mature segment length (15 worms, 26segments), 590 (180 to 1.1 mm); width (15worms, 26 segments), 525 (230 to 400). Detachedsegment length (5 segments), 2.6 mm (2to 3.5); width (5 segments), 570 (370 to 650).Cirrus pouch subspherical, extending W segmentwidth in mature segments; length (20 worms, 39pouches), 190 (112 to 230); width (20 worms.39 pouches), 106 (62 to 150). Cirrus armed, 900long; cirrus spine length, 3 to 5 at base, 8 to 10 atbulbous swelling, 7 at tip. Genital pore in posterior% of segment, irregularly alternating. Testessubspherical, 50 to 60 in diameter; number oftestes per segment (31 worms, 185 segments), 42e 4 (27 to 59); postvaginal testes (31 worms,185 segments), 6 e 1 (3 to 7); prevaginal testes(31 worms, 185 segments), 14 & 3 (9 to 19);antiporal testes (31 worms, 185 segments), 22 e3 ( 17 to 34). Ovarian lobes variable, usuallyabout equal, extending more than % distance tocirrus pouch, reaching level of cirrus pouch orbeyond in contracted segments; aporal lobe 676long by 70 wide; poral lobe 620 long by 50 wide.Vitelline acini 33 in diameter. Eggs 36 in diameter,oncospheres about 18 in diameter. Seminalreceptacle present.Hosts: Dasyatis centroura (Mitchill), northernstingray (type host); new host, D. americanaHildebrand and Schroeder, southern stingray; Rajaeglanteria Bosc, clear-nosed skate.Locality: Woods Hole, Massachusetts andChesapeake Bay, Virginia.RemarksLinton's (1890) brief description of A.paulum from D. centroura is inadequate todifferentiate this svecies from others subsequentlyrecovered, and no type specimenswere deposited in the Helminthological Collectionof the United States National Museumfrom the original collection. Only species fromanother collection, deposited in 1912, areavailable.Southwell ( 1925), upon examining Linton'smaterial sent to him as A. paulum from D.centroura, expanded Linton's original description,but considered Linton's specimens synonymouswith A. benedeni Loennberg, 1889,from European waters. Later, Baer (1948)examined Linton's material, finding that morethan one species was represented. Then fol-lowed Baer's (1948) description of A. woodsholei,listing A, coronaturn sensu Linton(1901) as a junior synonym, and redescriptionof A. paulum. Although comparative datacan be said to be insufficient from Linton'sdescriptions of A. paulum and A. breuissime,the redescription of A. paulum by Baer (1948)has provided salient characters which clearlyagree with the author's material in testes numberand distribution, hook size, total hooklength, and cirrus pouch measurements. Asseen in Table I the present redescription agreeswith Linton's (1890) original description, includingcirrus and cirrus spine measurements,and Baer's (1948) redescription. These charactersserve to clearly define A. paulum as adistinct species and I have found upon examinationof more than 100 worms, from R. eglanteriaand D. americana, sufficient variation toindicate that A. woodsholei should, at the presenttime, be considered a doubtful species andpossibly synonymous with A. paulum. Baer(1948) noted that the specimens he designatedas A. woodsholei from Linton's collectionwere contracted, which indicates thatfixation could account for the differences inaccessory sucker diameter, bothridial size, andapparent extent of ovarian lobes.Goldstein (1964) redescribed A. zc;oodsholzifrom the literature using Southwell's ( 1925)incomplete but compatible redescription ofA. paulum to expand Baer's (1948) descriptionof A. woodsholei, thereby placing A.paulum Linton (1890) in doubt, while Linton'soriginal description and Baer's (1948)incompatible redescription of A. paulum Linton,1890, which agree with the present material,are disregarded. Baer (1948) notedthat Linton's specimens labeled as A. paulum(1925) were not the same as the originalA. paulunz (1890) and placed A. paulum(1925) as a variation of A. filicolle Zschokke,1888. Because Southwell (1925) gives datafor only a few characters and no mean values,his description is of little value. In fact, hisdata are insufficient to distinguish it from anumber of species. The present author alsonotes that Goldstein's (1964) tabular presentationof Baer's original description of A.woodsholei disagrees in the following: ( 1)genital pore is not midmarginal but, "L'atriumgCnital s'ouvre un peu en arriAre du milieu du

CAMPBELL-NEW SPECIES OF ACANTHOBOTHRIUM FROM CHESAPEAKE BAY 569many species of Acanthobothrium may beutilizing many of the same intermediate hostscommon to the diets of the definitive hosts.Except for the work of Reichenbach-Klinke(1956) little information is at hand relative tothe relation between commonly reported"Scolex pleuronzctes" Miiller, 1788, and particularadults. Although host specificity is impliedfor elasmobranch cestodes there is noexperimental evidence to indicate whether aparticular species of Acanthobothritim from astingray is capable of infecting a skate or evena shark.In view of the increasing number of describedspecies of Acanthobothritim and becauseof the overlapping of diagnostic characteristics(testes number, hook measurements,etc.) one suspects that host-induced modificationsmay be involved. Unless experimentalwork is done this genus will soon be subjectto the taxonomic confusion exemplified by thegenus Hymenolvpis and others. That hostinducedmodifications are known to ocur hasbeen shown experimentally in trematodes byWatertor (1967), and in cestodes by James(1968). To consider host and locality dataas valid taxonomic criteria for differentiatingspecies of Acanthobothritim seems to be premature.An extensive and critical review ofthe genus based on experimental work, extensivecollections, examination of type specimens,and knowledge concerning the zoogeographyof the hosts involved is, therefore, essential.Key to species of Acanthobothriumfrom the western north Atlantic1. ( a) Postvaginal testes present ...................... 2 ( b ) Postvaginal testes absent ........................ ........................ A. foeeli Goldstein. 1964, -2. (a) Postvaginal testes 12 or less .................. 3 (b) Postvaginal testes 17 or more ................ 7 3. (a) Postvaginal testes 3 * l;*total hooklength 115 t 11 ...................................................... A. brevissime Linton, 1908(b) Postvaginal testes 5 to 10; total hooklength 140 or more .......................... 44. (a) Prevaginal testes about 9, usually tandemin arrangement ............................ 5(b) Prevaginal testes about 11 to 21, nottandem in arrangement ...................... 65. (a) Cirrus pouch in mature segments about198 long by 129 wide .............................................................. A. lineatum sp. n.* Mean value and the standard deviation. Alltestes numbers based on mature segments; hookmeasurements based on adult worms.(b) Cirrus pouch in mature segments about53 long by 39 wide .................................................... A. lintoni Goldstein, 19686. (a) Prevaginal testes about 11 to 14;T totalhook length 152 t 18 .................................................. A, paulum Linton, 1890(b) Prevaginal testes about 17 to 21; totalhook length 108 t 13 ..........................................A. floridensis Goldstein, 19647. (a) Prevaginal testes about 21;: total hooklength 200 or more .................................................... A. tortum ( Linton, 1916)(b) Prevaginal testes 12 t 2; total hooklength, 180 or less .............................................................. A. americanum sp. n.Acanthobothriztm u;oodsholei Baer, 1948: incertaesedis.i. Reevaluation of A. tortum has shown testesnumbers to be much greater. Redescription willbe presented elsewhere.ACKNOWLEDGMENTSI wish to express my appreciation to Dr.William J. Hargis, Jr., for the privilege ofusing the facilities of the Virginia Institute ofMarine Science; Dr. Newton R. Kingston,University of Wyoming, and Messrs. David E.Zwerner and Adrian R. Lawler of the Institutefor aid in collection and identification ofhosts; Dr. Robert J. Goldstein, Emory University,for aid in identification and donationof specimens from his collection; Dr. R. Martinand personnel of the Stazione Zoologica diNapoli (Naples, Italy) for use of laboratoryfacilities and aid in obtaining material forcomparison; and Dr. Martin J. Ulmer, IowaState University, for suggestions and criticismconcerning preparation of the manuscript. Thisstudy was supported in part by NSF grantGB5465X1 (under the direction of Dr. MartinJ. Ulmer).LITERATURE CITEDBAER,J. G. 1948. Contributions A l'ktude descestodes de sklaciens. I-IV. Bull. Soc. Sci.Nat. NeuchLtel 71: 63-122., AKD L. EUZET. 1962. Revision critiquedes cestodes tktraphyllides dkcrits par T.Southwell. Bull. Soc. Sci. Nat. NeuchLtel 85:143-172.BEAUCHAMP, P. M. DE. 1905. fitudes sur lescestodes des sklaciens. Arch. Parasit. 9: 463-539.GOLDSTEIS, R. J. 1964. Species of Acanthobothrium(Cestoda: Tetraphyllidea) from theGulf of Mexico. J. Parasit. 50: 656-661.. 1967. The genus Acanthobothrium VanBeneden, 1849 (Cestoda: Tetraphyllidea). J.Parasit. 53: 455-483.

570 THE JOURNAL OF PARASITOLOGY, VOL. 55, NO. 3, JUNE 1969, F. SCHLICHT, AND R. F. HANSON. 1968.Acanthobothrium lintoni n, sp. (Cestoda:Tetraphyllidea) from the electric ray, Narcinebrasiliensis (Olfers) in the Gulf of hlexico.Zool. Anz. In press.JAMES, H. A. 1968. Studies on the genus Mesocestoides(Cestoda: Cyclophyllidea). Ph.D.thesis, Iowa State Univ., University hlicrofilms,Inc., Ann Arbor, Michigan.JOYEUX, C., AND J. G. BAER. 1936. Cestodes( 1-163). Faune de France, XXX, Paris.LIKTON, E, 1890. Notes on the entozoa of marinefishes of New England. I1 Ann. Rept.U. S. Comm. Fish and Fisheries for 1887,Washington 15: 719-899.. 1901. Parasites of fishes of the WoodsHole region. Bull. U. S. Comm. Fish andFisheries for 1889. 19: 405-492.. 1908. Helminth fauna of the DryTortugas. 1. Cestodes. Carnegie Inst. Wash.Publ. 102, p. 157-190.REGAN,J. D. 1963. A cestode plerocercoid fromthe crowned conch. Quar. J. Fla. Acad. Sci.26: 184-187.REICHENBACH-KLIKKE, H. H. 1956. Artzugehorigkeitund Entwicklung der als Scolexpleuronectis Miiller bekannten Cestodenlarven(Cestoidea, Tetraphyllidea) Verhandl. D.Zool. Gesell, p. 317-324.SOUTHWELL, T. 1925. A monograph on theTetraphyllidea, with notes on related cestodes.Mem. Liverpool School Trop. Med.New Ser., 2. Liverpool Cniv. Press, 368 p.WATERTOR,J. L.1967. Intraspecific variationof adult Telorchis bonnerensis (Trematoda:Telorchiidae) in amphibian and reptilianhosts. J. Parasit. 53: 962-968.

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