James R. Palmieri

Comparative host reaction to Angiostrongylus malaysiensis (Nematoda) in three species of snails

Abstract Infection with Angiostrongylus malaysiensis was studied by means of tissue squash preparations and histological sections in three species of Malaysian aquatic snails: Lymnaea rubiginosa, Physastra sumatrana , and Melanoides tuberculata . Development to the third stage occurred normally in L. rubiginosa . The biphasic tissue reaction in this snail was similar to that described in Biomphalaria glabrata infected with A. cantonensis . However, the final architecture of the granuloma differed in the two hosts with the cells in the L. rubiginosa granuloma often appearing more vacuolated and less flattened. Nematode development in P. sumatrana was abnormal, with larvae beyond the early first stage occurring in only 21% of infected snails. The highly variable cellular reactions against larvae in P. sumatrana , even within the same snail, probably reflect the differing degrees of maturation attained by individual larvae. Except in one case, no infection of M. tuberculata occurred, presumably as a result of its impenetrable epithelia.

Mesocoelium malayanum sp. n. (Digenea: Brachycoeliidae) in a frog, Rana macrodon Dumeril and Bibron 1941, from Malaysia.

Mesocoelium malayanum sp. n. is described from the frog Rana macrodon, in Malaysia. Elongate body, broader anteriorly, measuring 1.900 (1.679-2.070) mm long by 0.404 (0.380-0.437) wide, tegument aspinose oral sucker 0.212 (0.200-0.228) by 0.202 (9.191-0.205), acetabulum 0.141 (0.132-0.150) by 0.139 (0.123-0.146), prepharynx present, oesophagus 0.115 (0.096-0.137), caeca reaching posterior 1/3 of body, anterior testis 0.097 (0.087-0.110) by 0.091 (0.087-0.100) dorsal to acetabulum, posterior testis 0.094 (0.087-0.101) by 0.092 (0.091-0.100), cirrus pouch 0.121 (0.111-0.130) by 0.047 (0.041-0.055), genital pore at left of midline of oesophagus just anterior to intestinal bifurcation, ovary 0.110 (0.091-0.127) by 0.089 (0.085-0.096) on left of body and posterior to acetabulum, vitelline glands with single follicles extending from intestinal bifurcation to ends of caeca, excretory vesicle I-shaped and eggs 0.040 (0.037-0.046) by 0.023 (0.022-0.024). Although morphologically related to M. maroccanum and M. meggitti, M. malayanum is considered to be a new species.

Parasites of the lesser one-horned rhinoceros (Rhinoceros sondaicus Desmarest).

MACKERRAS, M. J. 1958. Catalogue of Australian mammals and their recorded internal parasites. Proc. Linn. Soc. N. S. W. 83: 101-160. MILLER, A. 1977. Parasites of the eastern water rat, Hydromys chrysogaster Geoffroy 1804, of south eastern Australia. Thesis, Univ. Melbourne, B. An. Sci. 44 p. OLSEN, 0. W. 1968. Uncinaria rauschi (Strongyloidea: Nematoda), a new species of hookworms from Alaskan bears. Can. J. Zool. 46: 1113-1117. PARONA, C. 1907. Nuove specie di Nematodi africani (nota preventiva). Boll. Mus. Zool. Anat. Comp. Univ. Torino 22: 1-4. WOLFGANG, R. W. 1956. Dochmoides yukonensis sp. nov. from the brown bear (Ursus americanus) in the Yukon. Can. J. Zool. 34: 21-27.

EFFECT OF DURATION AND INTENSITY OF INFECTION WITH ECHINOSTOMA AUDYI ON SURVIVAL OF LYMNAEA RUBIGINOSA EXPOSED TO COPPER SULFATE

Lymnaea rubiginosa infected with 1 to 5 miracidia of Echinostoma audyi for 1, 2, 3, and 5 weeks, and snails infected with up to 10 or 20 miracidia for 3 weeks, were exposed to copper (Cu) as CuSO4 2 hr and allowed to recover 48 hr. In general, snails ininfected with up to 5 miracidia of E. audyi were no more susceptible to Cu than noninfected snails. Snails infected with up to 10 miracidia for 3 weeks were 1.3 times more susceptible to Cu than noninfected snails. However, snails infected with up to 20 miracidia for 3 weeks were not more susceptible to Cu, possibly because infection with such a large number of parasites eliminated the most susceptible snails from the population prior to exposure to Cu.

Fibricola ramachandrani (Betterton, 1976) Palmieri, Krishnasamy and Sullivan comb. nov. from Malaysian rodent hosts with a special note on intraspecific morphological variation

Neodiplostomum (Conodiplostomum) ramachandrani Betterton, 1976 has been reported from four species of rodent hosts: Echinosorex gymnurus (Raffles): Rattus whiteheadi (Thos); R. muelleri (Jentink) and Callosciurus notatus (Boddaert). A comparison of trematodes recovered from these hosts revealed patterns of host-induced morphological variation taking place. Because N. (Conodiplostomum) ramachandrani shows little generic difference from Fibricola intermedius (Pearson, 1959) Sudarikov, 1960 it is transferred to the genus Fibricola and is now designated Fibricola ramachandrani (Betterton, 1976) Palmieri, Krishnasamy and Sullivan.

Daubaylia malayanum sp. n. (Nematoda: Cephalobidae), a Parasite of Malaysian Pulmonate Snails, with Observations on Its Life History

Daubaylia malayanum sp. n. is reported from Gyraulus convexiusculus based on the in utero egg development and the male genital papillae. The life cycle of D. malayanum is similar to that of D. potomaca. The nematode is an obligate parasite and survives less than 1 week outside the snail. Snails initially are infected when penetrated by gravid female worms. Egg deposition and larval maturation occur within the snail. Development from egg to adult requires approximately 11 days, with the great majority of adult progeny being females. Baylis and Daubney (1922) reported Cephalobus seistanensis, a nematode parasite of the pulmonary cavity of Persian Gyraulus convexiusculus. Chitwood and Chitwood (1934) proposed the new genus Daubaylia for this nematode and also named a second species, D. potomaca, that parasitized Helisoma trivolvis from Virginia, USA. More recently, D. dewiti, from Planorbis contortus (Schuurmans Stekhoven, 1956) and D. elegans from P. carinatus (Honer and Jansen, 1961) have been described in Holland. In the present study a fifth species of Daubaylia is reported from G. convexiusculus Hutton 1849 in Malaysia. Species of Daubaylia are of interest because Chernin (1962) reported that D. potomaca is entirely parasitic in pulmonate snails, and Biomphalaria glabrata infected with D. potomaca die within 44 days. Hence, these unusual parasites merit consideration as possible biological control agents of schistosome-transmit-

Strigeoid trematodes of Malaysia with descriptions of a new genus and three new species

Six species of strigeoid trematodes are reported from Malaysia. One new genus and 3 new species are described: Apatemon (Apatemon( jamesi sp. n (Strigeidae); cercaria Cotylurus sullivani sp. n. (Strigeidae); Neodiplostomum (Neodiplostomum) sp. (Diplostomatidae); Fibricola ramachandrani (Diplostomatidae); Pseudoscolopacitrema otteri gen. n. et sp. n. (Diplostomatidae); and cercaria Cyathocotyle malayi sp. n. (Cyathocotylidae). The life cycles of A. jamesi and C. malayi have also been investigated.

Occurrence of a sporocyst generation of Fasciola gigantica in the mollusc Lymnaea rubiginosa.

Thirty laboratory-reared, juvenile Lymnae rubiginosa were exposed to 20 miracidia each of Fasciola gigantica. Eight days postinfection snails were dissected, and clearly recognizable sporocysts were recovered from the mantle collar and renal vein. Behavior of sporocysts and mother rediae differed markedly. These observations contradict those of direct metamorphosis of miracidium into redia as reported by Ogambo-Ongoma and Goodman (1976).

Stunkardia minuta sp. n. (Trematoda: Paramphistomidae) from the Malayan box-tortoise Cuora amboinensis.

Stunkardia minuta sp. n. was recovered from the small intestine and rectum of 5 box-tortoises (Cuora amboinensis) in Malaysia. The average body size (L X W) is 11-42 X 2-35 mm; oral sucker 1-51 X 1.02; oral pouches 0-21 X 0.18; ventral sucker 1-67 X 1-43; oesophageal bulb 0-54 X 0-54; ant. testis 0-95 X 0-98; post. testis 0-94 X 0.94; seminal vesicle 0-82 X 0-24; ootype 0-21 X 0-41; ovary 0-41 X 0-34; and egg 121 X 83 micrometer. Although morphologically similar to S. dilymphosa, S. minuta is distinct from any other reported member of the Paramphistomidae.

Castroia kamariae sp. nov. and Limatulum kuziai sp. nov. (Lecithodendriidae) from the free-tailed bat (Tadarida mops de Blainville) from West Malaysia.

Thirteen bats, Tadarida mops de Blainville, collected from the Ampang district in Kuala Lumpur, Malaysia, were found positive for the trematodes Castroia kamariae sp. nov. and Limatulum kuziai sp. nov. Two distinct but morphologically similar forms of Castroia kamariae were recovered. The morphological type is apparently determined by its location in the host intestine.