Journal of Helminthotogy (1978) 52, 215-220
Paratrichosoma crocodilus n. gen. n. sp. (Nematoda: Trichosomoididae) from the skin of the New Guinea crocodile R. W. ASHFORD Department of Pathology, University of Papua New Guinea and Liverpool School of Tropical Medicine, Pembroke Place, Liverpool and RALPH MULLER London School of Hygiene and Tropical Medicine, Keppel Street, London JVC IE 1HT {Reprint address) ABSTRACT A new genus of nematode (Paratrichosoma crocodilus) is described from Crocodilus novaeguinae. Adults have typical trichuroid features but elongated stichocytes (over 1 mm in female). Males are one third to one half as long as females and have no spicule or sheath.
The presence of serpentine tunnels in the belly skin of crocodilians is well recognised in the skin trade. King and Brazaitas (1971) discussed and illustrated worm-trails seen in five species of crocodiles and Dr. H. I. Jones (personal communication) has noted their presence in skins from Papua New Guinea and Northern Australia. The official policy for the conservation of the New Guinea crocodile, Crocodilus novaeguineae novaeguinae, includes the rearing of small wild caught specimens to a more economically desirable size. It has been found that many of the crocodiles reared experimentally in this way become conspicuously marked with skin worm trails, which decreases their value. These trails were therefore investigated with a view to eventual economic assessment of the problem and recommendation of possible control measures. The prevalence of infection in wild and captive populations is being studied as is its distribution in crocodiles from different habitats. Preliminary results indicate that both C. novaeguineae and C. porosus are susceptible, that the parasite is rare or absent in crocodiles from areas of saline water, and that transmission does not occur in some rearing conditions. These results will be fully reported in due course. The purpose of the present paper is to describe the causative parasite. The crocodiles used in this study were all C. novaeguineae from the Government demonstration crocodile "farm" at Moitaka, Port Moresby. All had been captured wild in various parts of the country. Data on the original sources was not available. The smallest specimens with visibly affected skin were selected, as worms were more easily extracted from small skins. The specimens from which worms were isolated varied from 30 to 50 cm in length. Eggs in the trails were clearly visible by superficial examination with a dissecting microscope, but no way was found to follow the trails to the deeper levels of the living epidermis where the adults live. Entire skins were therefore treated for up to 10 hr at 50cC in a 1 % solution of papain. This made it possible to peel off an outer layer, which included the cuticularised outer layer and most of the living epidermis, leaving the leathery dermis (Plate, Fig. 1). The worms were then found by minute scrutiny of the underside of the outer layer with a dissecting microscope. A maximum of four worms were found in any one skin although it is probable that some were missed. Fourth stage larvae were also found in the skin. Adult worms obtained by dissection were fixed in hot AFA and stored in 70 % alcohol containing 10% glycerol. Specimens were examined in glycerol and in lactophenol. 215
R. W. ASHFORD and R. MULLER
Sections were made of 150 pieces cut from an entire skin preserved in formol saline in the hope of sectioning a worm. Although deep burrows with unembryonated eggs were sectioned, no worms were found by this method. PARATRICHOSOMA CROCODILUS gen. et sp. nov. (Table 1 and Figs. 1-6) Description: Trichuroidea Railliet, 1916. Trichosomoididae Yorke and Maplestone, 1926. Anatrichosomatinae Smith and Chitwood, 1958. Paratrichosoma Ashford and Muller, 1978. Slender, thread-like nematodes 2 to 7 cm long; body divided into thinner forebody containing oesophagus and stichosome and broader posterior body containing intestine and reproductive system. Cuticle thick with numerous pores. Oesophagus one third to one half total length. Well developed valve at junction of oesophagus and intestine (Fig. 4); latter narrow and straight with a terminal anus. Stichosome composed of 32-37 cells. Individual stichocytes extremely elongated (over 1 mm in the female). Length of female twice to three times that of male, diameter approximately double. Bacillary bands not seen. All measurements in millimetres unless otherwise stated. Female (based on holotype and 3 paratypes): Mature specimens 69.5 (58.5-81) in length, 145 (100-167) urn in maximum width, 20.4 (18.4-22.7) from anterior end to vulva, 0.26 (0.18-0.33) in length of muscular portion of the oesophagus. Ratio of body length to length of oesophagus 3.3 to 3.7:1. Stichocytes number 33 to 37, much longer than wide and reaching a maximum length of 1.33 about 5 mm from anterior end (Fig. 2). Eggs thick shelled and bioperculate, length 0.060, width 0.033. The eggs are unembryonated when laid but they develop during the time they remain in the skin, and contain a fully formed larvae when epidermis is sloughed off. Male: Two complete specimens (22.7-28 long) and one lacking tail end. Width almost uniform. Tail truncate in ventral view with no papillae evident (Fig. 6). No spicule, spicule sheath, or cirrus. Maximum width 80-83; length of muscular oesophagus 0.22 (0.16-0.30); distance from anterior end to end of stichosome 13.2 (11.6-16). Stichocytes number 32-36, much longer than wide and having a maximum length of up to 0.40. Host: Crocodilus novaeguineae. Habitat: In tunnels in the epidermis of skin of abdomen. Locality: Papua New Guinea (found at Moitaka, Port Moresby). Holotype female: British Museum (Natural History) coll. No. 1978/915. Other specimens: British Museum (Natural History) coll. No. 1978/916-920. DISCUSSION There have been few records of trichuroid nematodes from reptiles apart from species of the large and widely distributed genus, Capillaria (Skrjabin et ah, 1957; Yamaguti, 1961). However, the males of all species of this genus have copulatory sheath and usually a spicule. Three species of Dioctowittus have been described from the body cavity of snakes; but in this genus the intestine is transformed into a trophosome and the vulva of the female opens near the anterior end (Chabaud and Le Van Hoa, 1960; Bain and Ghadirian, 1967; Jones, 1978). Paratrichosoma fits well into the subfamily Anatrichosomatinae as defined by Chitwood and Smith (1958). This is a previously monogeneric subfamily with Anatrichosoma cynamolgi Smith and Chitwood, 1954 described from the nasal mucosa of the cynomolgus monkey, 216
Paratrichosoma crocodilus n. gen. n. sp. from crocodile
FIGS. 1-6. Paratrichosoma crocodilus n. gen. n. sp. FIG. 1. Female, anterior end; FIG. 2. Female, forebody 5 mm from anterior end showing length of a single stichocyte; FIG. 3. Female, posterior end; FIG. 4. Female, lateral view of vulva and oesophagointestinal valve; FIG. 5. Egg from uterus, containing a larva; FIG. 6. Male, posterior end. 217
28
(incomplete)
25
58.5
69
32
81
Male 2
Male 3
Female 4
Female 5
Female 6 (immature)
Female 7
Length
Male 1
Specimens
167
70
100
167
83
—
80
Maximum width (urn)
0.30 0.23 0.23 0.18
36 0.40 34 1.25 34 0.93 34 0.43 33-37 1.33
83 67 130
83
66
0.33
0.20
34 0.33
58
67
—
—
—
—
16
12
11.6
22.7
14
20
18.4
—
—
—
Distance from anterior Distance from end to anterior end Distance from beginning of anterior end to end of stichosome stichosome to vulva 0.16
Mo. of stichocytes and maximum length 32-36 0.30
Width at last stichocyte (Urn)
TABLE 1 Measurements of specimens of Paratrichosoma crocodilus n.gen. n.sp. (in millimetres unless otherwise stated)
3.7:1
2.3:1
3.6:1
3.3:1
1.6:1
—
2.5:1
Ratio of body length to length of oesophagus
ASHFORD and R. MULLER
Paratrichosoma crocodilus n. gen. n. sp. from crocodile A. cutaneum (Swift, Boots and Miller, 1922) Chitwood and Smith, 1958 from the skin of rhesus monkeys, A. rhina Conrad and Wong, 1973 and A. nacepobi Conrad and Wong, 1973, from the nasal mucosa of rhesus monkeys (these last two species, however, were regarded as synonyms of A. cynamolgi by Long et al. in 1976), A buccalis Pence and Little, 1972, from the buccal mucosa of an oppossum and A. ocularis File, 1974, from the cornea of a tree shrew. Paratrichosoma differs from Anatrichosoma in that the male is only one quarter to one third the size of the female instead of being roughly equal in size, and in the presence of the curious very elongated stichocytes, measuring over a millimetre in length in the female. Other differentiating features are the absence of a buccal stylet and of caudal papillae in the male of the former genus. Females of a parasite named Trichosoma recurva (transferred to genus Capillaria by Travassos in 1915) were described by Solger (1877) from the abdominal skin of Crocodilus americanus and C. acutus in Mexico. They were 70-75 mm long by 90-100 um wide, with a vulva 25 mm from the anterior end and eggs measuring 0.063 by 0.03 mm. The description is similar to the present worms and it is considered that they belong to the same genus. A new species has been erected for the worms from New Guinea as Solger's description is really too brief for comparison and there are differences in the appearance of the tail of the female and some variation in measurements. Paratrichosoma extends the host range of the family Trichosomoididae, all previous members having been found in mammals. ACKNOWLEDGEMENTS Mr. F. Parker, Assistant Secretary for Wildlife, Department of Natural Resources, and Mr. J. Lever, Project Manager of the National Crocodile Project, and their colleagues are to be thanked for drawing our attention to this problem, for providing specimens, and for their extensive co-operation. Messrs. D. D. Morison and N. Iaubihi of the Department of Human Biology, University of Papua New Guinea, provided skilled technical assistance. Thanks are due to Mr. M. D. Smith for the scanning electron micrographs and to Miss Hazel Falconer for typing the manuscript. REFERENCES BAIN, O. and GHADIRIAN, E. (1967) Description d'une nouvelle espece de Dioctowittus (Nematode) et note sur la position systematique du genre. Annales de Parasitologie, 42, 643-650. CHABAUD, A. G. and LE VAN HOA (1960) Nematodes parasites de Reptiles. Aphasmidiens. Pare National de Upemba. Mission G. F. de Witte, 65, 59-64. CHITWOOD, M. B. and SMITH, W. N. (1958) A redescription of Anatrichosoma cynamolgi Smith and Chitwood, 1954. Proceedings of the Helminthological Society of Washington, 25, 112-117. CONRAD, H. D. and WONG, M. M. (1973) Studies of Anatrichosoma (Nematoda: Trichinellida) with descriptions of Anatrichosoma rhina sp. n. and Anatrichosoma nacepobi sp. n. from the nasal mucosa of Macaca mulatto. Journal of Helminthology, 47, 289-302. FILE, S. K. (1974) Anatrichosoma ocularis sp. n. (Nematoda: Trichosomoididae) from the eye of the common tree shrew, Tupaia glis. The Journal of Parasitology, 60, 985-988. JONES, H. I. (1978) Dioctowittus spp. Chabaud and Le Van Hoa 1960 (Nematoda: Adenophorea) from Australian snakes. Journal of Helminthology, 52, 141-145. KING, F. W. and BRAZAITIS, P. (1971) Species identification of commercial crocodile skins, Zoologica (New York), 56, 15-75. LONG, G. p . , LICHTENFELS, J. R. and STOOKEY, J. L. (1976) Anatrichosoma cynamolgi (Nematoda: Trichinellida) in rhesus monkeys, Macaca mulatto. The Journal of Parasitology, 62, 111-115. PENCE, D. B. and LITTLE, M. D. (1972) Anatrichosoma buccalis sp. n. (Nematoda: Trichosomoididae) from the buccal mucosa of the common opossum Didelphis marsupialis L. The Journal of Parasitology, 58, 767-773. SKRJABIN, K. E., SHIKHOBALOVA, N. P. and ORLOV, I. V. (1957) Trichocephalidae and Capillariidae of animals and man and the diseases caused by them. Essentials of Nematology vol. 6 Akademiya Nauk SSR (English translation by Israel program for Scientific translations: Jerusalem 1970). SMITH, W. N. and CHITWOOD, M. B. (1954) Anatrichosoma cynamolgi, a new trichurid nematode from monkeys. The Journal of Parasitology, 40 (suppl.), 12. 219
R. W. ASHFORD and R. MULLER SOLGER, B. (1877) Uber eine neue Species von Trichosoma R. Archiv fur Naturgeschichte, 43, 1, 19-23. TRAVASSOS, L. (1915) Contribuigoes para o conhecimento da fauna helminthologica brasiliera. Sobre as especies brasileiras do genero Capillaria Zeder, 1800. Memorias do Institute Oswaldo Cruz, 7, 146-172. YAMAGUTI, S. (1961) Systema Helminthum. vol. 3 Nematodes. Interscience: New York and London. Received 23 January, 1978.
220
%
* :
•
1
—
' ,
'"••'
%
'
%
' " • ' " ' :
'.
"
'
,.|
~x*.~:v
PLATE FIG. 1. Epidermis of crocodile with worm in situ after papain digestion; FIG. 2. Portion of cuticle of adult female worm (mag. X 1080); FIG. 3. Scanning electron micrograph of portion of female worm to show pores in cuticle (mag. X 4050).
Paratrichosoma crocodilus n. gen. n. sp. (Nematoda: Trichosomoididae) from the skin of the New Guinea crocodile R. W. ASHFORD Department of Pathology, University of Papua New Guinea and Liverpool School of Tropical Medicine, Pembroke Place, Liverpool and RALPH MULLER London School of Hygiene and Tropical Medicine, Keppel Street, London JVC IE 1HT {Reprint address) ABSTRACT A new genus of nematode (Paratrichosoma crocodilus) is described from Crocodilus novaeguinae. Adults have typical trichuroid features but elongated stichocytes (over 1 mm in female). Males are one third to one half as long as females and have no spicule or sheath.
The presence of serpentine tunnels in the belly skin of crocodilians is well recognised in the skin trade. King and Brazaitas (1971) discussed and illustrated worm-trails seen in five species of crocodiles and Dr. H. I. Jones (personal communication) has noted their presence in skins from Papua New Guinea and Northern Australia. The official policy for the conservation of the New Guinea crocodile, Crocodilus novaeguineae novaeguinae, includes the rearing of small wild caught specimens to a more economically desirable size. It has been found that many of the crocodiles reared experimentally in this way become conspicuously marked with skin worm trails, which decreases their value. These trails were therefore investigated with a view to eventual economic assessment of the problem and recommendation of possible control measures. The prevalence of infection in wild and captive populations is being studied as is its distribution in crocodiles from different habitats. Preliminary results indicate that both C. novaeguineae and C. porosus are susceptible, that the parasite is rare or absent in crocodiles from areas of saline water, and that transmission does not occur in some rearing conditions. These results will be fully reported in due course. The purpose of the present paper is to describe the causative parasite. The crocodiles used in this study were all C. novaeguineae from the Government demonstration crocodile "farm" at Moitaka, Port Moresby. All had been captured wild in various parts of the country. Data on the original sources was not available. The smallest specimens with visibly affected skin were selected, as worms were more easily extracted from small skins. The specimens from which worms were isolated varied from 30 to 50 cm in length. Eggs in the trails were clearly visible by superficial examination with a dissecting microscope, but no way was found to follow the trails to the deeper levels of the living epidermis where the adults live. Entire skins were therefore treated for up to 10 hr at 50cC in a 1 % solution of papain. This made it possible to peel off an outer layer, which included the cuticularised outer layer and most of the living epidermis, leaving the leathery dermis (Plate, Fig. 1). The worms were then found by minute scrutiny of the underside of the outer layer with a dissecting microscope. A maximum of four worms were found in any one skin although it is probable that some were missed. Fourth stage larvae were also found in the skin. Adult worms obtained by dissection were fixed in hot AFA and stored in 70 % alcohol containing 10% glycerol. Specimens were examined in glycerol and in lactophenol. 215
R. W. ASHFORD and R. MULLER
Sections were made of 150 pieces cut from an entire skin preserved in formol saline in the hope of sectioning a worm. Although deep burrows with unembryonated eggs were sectioned, no worms were found by this method. PARATRICHOSOMA CROCODILUS gen. et sp. nov. (Table 1 and Figs. 1-6) Description: Trichuroidea Railliet, 1916. Trichosomoididae Yorke and Maplestone, 1926. Anatrichosomatinae Smith and Chitwood, 1958. Paratrichosoma Ashford and Muller, 1978. Slender, thread-like nematodes 2 to 7 cm long; body divided into thinner forebody containing oesophagus and stichosome and broader posterior body containing intestine and reproductive system. Cuticle thick with numerous pores. Oesophagus one third to one half total length. Well developed valve at junction of oesophagus and intestine (Fig. 4); latter narrow and straight with a terminal anus. Stichosome composed of 32-37 cells. Individual stichocytes extremely elongated (over 1 mm in the female). Length of female twice to three times that of male, diameter approximately double. Bacillary bands not seen. All measurements in millimetres unless otherwise stated. Female (based on holotype and 3 paratypes): Mature specimens 69.5 (58.5-81) in length, 145 (100-167) urn in maximum width, 20.4 (18.4-22.7) from anterior end to vulva, 0.26 (0.18-0.33) in length of muscular portion of the oesophagus. Ratio of body length to length of oesophagus 3.3 to 3.7:1. Stichocytes number 33 to 37, much longer than wide and reaching a maximum length of 1.33 about 5 mm from anterior end (Fig. 2). Eggs thick shelled and bioperculate, length 0.060, width 0.033. The eggs are unembryonated when laid but they develop during the time they remain in the skin, and contain a fully formed larvae when epidermis is sloughed off. Male: Two complete specimens (22.7-28 long) and one lacking tail end. Width almost uniform. Tail truncate in ventral view with no papillae evident (Fig. 6). No spicule, spicule sheath, or cirrus. Maximum width 80-83; length of muscular oesophagus 0.22 (0.16-0.30); distance from anterior end to end of stichosome 13.2 (11.6-16). Stichocytes number 32-36, much longer than wide and having a maximum length of up to 0.40. Host: Crocodilus novaeguineae. Habitat: In tunnels in the epidermis of skin of abdomen. Locality: Papua New Guinea (found at Moitaka, Port Moresby). Holotype female: British Museum (Natural History) coll. No. 1978/915. Other specimens: British Museum (Natural History) coll. No. 1978/916-920. DISCUSSION There have been few records of trichuroid nematodes from reptiles apart from species of the large and widely distributed genus, Capillaria (Skrjabin et ah, 1957; Yamaguti, 1961). However, the males of all species of this genus have copulatory sheath and usually a spicule. Three species of Dioctowittus have been described from the body cavity of snakes; but in this genus the intestine is transformed into a trophosome and the vulva of the female opens near the anterior end (Chabaud and Le Van Hoa, 1960; Bain and Ghadirian, 1967; Jones, 1978). Paratrichosoma fits well into the subfamily Anatrichosomatinae as defined by Chitwood and Smith (1958). This is a previously monogeneric subfamily with Anatrichosoma cynamolgi Smith and Chitwood, 1954 described from the nasal mucosa of the cynomolgus monkey, 216
Paratrichosoma crocodilus n. gen. n. sp. from crocodile
FIGS. 1-6. Paratrichosoma crocodilus n. gen. n. sp. FIG. 1. Female, anterior end; FIG. 2. Female, forebody 5 mm from anterior end showing length of a single stichocyte; FIG. 3. Female, posterior end; FIG. 4. Female, lateral view of vulva and oesophagointestinal valve; FIG. 5. Egg from uterus, containing a larva; FIG. 6. Male, posterior end. 217
28
(incomplete)
25
58.5
69
32
81
Male 2
Male 3
Female 4
Female 5
Female 6 (immature)
Female 7
Length
Male 1
Specimens
167
70
100
167
83
—
80
Maximum width (urn)
0.30 0.23 0.23 0.18
36 0.40 34 1.25 34 0.93 34 0.43 33-37 1.33
83 67 130
83
66
0.33
0.20
34 0.33
58
67
—
—
—
—
16
12
11.6
22.7
14
20
18.4
—
—
—
Distance from anterior Distance from end to anterior end Distance from beginning of anterior end to end of stichosome stichosome to vulva 0.16
Mo. of stichocytes and maximum length 32-36 0.30
Width at last stichocyte (Urn)
TABLE 1 Measurements of specimens of Paratrichosoma crocodilus n.gen. n.sp. (in millimetres unless otherwise stated)
3.7:1
2.3:1
3.6:1
3.3:1
1.6:1
—
2.5:1
Ratio of body length to length of oesophagus
ASHFORD and R. MULLER
Paratrichosoma crocodilus n. gen. n. sp. from crocodile A. cutaneum (Swift, Boots and Miller, 1922) Chitwood and Smith, 1958 from the skin of rhesus monkeys, A. rhina Conrad and Wong, 1973 and A. nacepobi Conrad and Wong, 1973, from the nasal mucosa of rhesus monkeys (these last two species, however, were regarded as synonyms of A. cynamolgi by Long et al. in 1976), A buccalis Pence and Little, 1972, from the buccal mucosa of an oppossum and A. ocularis File, 1974, from the cornea of a tree shrew. Paratrichosoma differs from Anatrichosoma in that the male is only one quarter to one third the size of the female instead of being roughly equal in size, and in the presence of the curious very elongated stichocytes, measuring over a millimetre in length in the female. Other differentiating features are the absence of a buccal stylet and of caudal papillae in the male of the former genus. Females of a parasite named Trichosoma recurva (transferred to genus Capillaria by Travassos in 1915) were described by Solger (1877) from the abdominal skin of Crocodilus americanus and C. acutus in Mexico. They were 70-75 mm long by 90-100 um wide, with a vulva 25 mm from the anterior end and eggs measuring 0.063 by 0.03 mm. The description is similar to the present worms and it is considered that they belong to the same genus. A new species has been erected for the worms from New Guinea as Solger's description is really too brief for comparison and there are differences in the appearance of the tail of the female and some variation in measurements. Paratrichosoma extends the host range of the family Trichosomoididae, all previous members having been found in mammals. ACKNOWLEDGEMENTS Mr. F. Parker, Assistant Secretary for Wildlife, Department of Natural Resources, and Mr. J. Lever, Project Manager of the National Crocodile Project, and their colleagues are to be thanked for drawing our attention to this problem, for providing specimens, and for their extensive co-operation. Messrs. D. D. Morison and N. Iaubihi of the Department of Human Biology, University of Papua New Guinea, provided skilled technical assistance. Thanks are due to Mr. M. D. Smith for the scanning electron micrographs and to Miss Hazel Falconer for typing the manuscript. REFERENCES BAIN, O. and GHADIRIAN, E. (1967) Description d'une nouvelle espece de Dioctowittus (Nematode) et note sur la position systematique du genre. Annales de Parasitologie, 42, 643-650. CHABAUD, A. G. and LE VAN HOA (1960) Nematodes parasites de Reptiles. Aphasmidiens. Pare National de Upemba. Mission G. F. de Witte, 65, 59-64. CHITWOOD, M. B. and SMITH, W. N. (1958) A redescription of Anatrichosoma cynamolgi Smith and Chitwood, 1954. Proceedings of the Helminthological Society of Washington, 25, 112-117. CONRAD, H. D. and WONG, M. M. (1973) Studies of Anatrichosoma (Nematoda: Trichinellida) with descriptions of Anatrichosoma rhina sp. n. and Anatrichosoma nacepobi sp. n. from the nasal mucosa of Macaca mulatto. Journal of Helminthology, 47, 289-302. FILE, S. K. (1974) Anatrichosoma ocularis sp. n. (Nematoda: Trichosomoididae) from the eye of the common tree shrew, Tupaia glis. The Journal of Parasitology, 60, 985-988. JONES, H. I. (1978) Dioctowittus spp. Chabaud and Le Van Hoa 1960 (Nematoda: Adenophorea) from Australian snakes. Journal of Helminthology, 52, 141-145. KING, F. W. and BRAZAITIS, P. (1971) Species identification of commercial crocodile skins, Zoologica (New York), 56, 15-75. LONG, G. p . , LICHTENFELS, J. R. and STOOKEY, J. L. (1976) Anatrichosoma cynamolgi (Nematoda: Trichinellida) in rhesus monkeys, Macaca mulatto. The Journal of Parasitology, 62, 111-115. PENCE, D. B. and LITTLE, M. D. (1972) Anatrichosoma buccalis sp. n. (Nematoda: Trichosomoididae) from the buccal mucosa of the common opossum Didelphis marsupialis L. The Journal of Parasitology, 58, 767-773. SKRJABIN, K. E., SHIKHOBALOVA, N. P. and ORLOV, I. V. (1957) Trichocephalidae and Capillariidae of animals and man and the diseases caused by them. Essentials of Nematology vol. 6 Akademiya Nauk SSR (English translation by Israel program for Scientific translations: Jerusalem 1970). SMITH, W. N. and CHITWOOD, M. B. (1954) Anatrichosoma cynamolgi, a new trichurid nematode from monkeys. The Journal of Parasitology, 40 (suppl.), 12. 219
R. W. ASHFORD and R. MULLER SOLGER, B. (1877) Uber eine neue Species von Trichosoma R. Archiv fur Naturgeschichte, 43, 1, 19-23. TRAVASSOS, L. (1915) Contribuigoes para o conhecimento da fauna helminthologica brasiliera. Sobre as especies brasileiras do genero Capillaria Zeder, 1800. Memorias do Institute Oswaldo Cruz, 7, 146-172. YAMAGUTI, S. (1961) Systema Helminthum. vol. 3 Nematodes. Interscience: New York and London. Received 23 January, 1978.
220
%
* :
•
1
—
' ,
'"••'
%
'
%
' " • ' " ' :
'.
"
'
,.|
~x*.~:v
PLATE FIG. 1. Epidermis of crocodile with worm in situ after papain digestion; FIG. 2. Portion of cuticle of adult female worm (mag. X 1080); FIG. 3. Scanning electron micrograph of portion of female worm to show pores in cuticle (mag. X 4050).
