Non-metric characters in two species of Sotalia (Gray, 1866) (Cetacea, Delphinidae)/Caracteres nao metricos nas duas especies de Sotalia (Gray, 1866).
The genus Sotalia (Gray, 1866) was until recently considered monospecific, however recent molecular genetics (Cunha et al., 2005; Caballero et al., 2007), and geometric morphometric (Monteiro-Filho et al., 2002) studies revealed the existence of two species: the marine species Sotalia guianensis (P.J. van Beneden, 1864) (gray dolphin) and the riverine species Sotalia fluviatilis (Gervais, 1853) (tucuxi).
The marine species is broadly distributed along the tropical and subtropical Atlantic coast of South and Central America, having been recorded from Florianopolis, Santa Catarina, Brazil (27[degrees] 35' S and 48[degrees] 34' W) (Simoes-Lopes, 1988; Borobia, 1989) to Honduras (15[degrees] 58' N and 85[degrees] 42' W) (da Silva and Best, 1996). The riverine species is endemic to the Amazon Basin, occurring from Belem (at the mouth of the Amazon River), in Brazil, to the rivers of Peru, Colombia and Ecuador (Borobia et al., 1991, da Silva and Best, 1996).
Osteological descriptions for the genus Sotalia have been published by Miranda-Ribeiro (1936); Casinos et al. (1981); Borobia (1989); Menezes and SimoesLopes (1996); da Silva and Best (1996); Alves Junior and Monteiro-Neto (1999); Avila et al. (2002); Fettuccia and Simoes-Lopes (2004), Simoes-Lopes (2006). With the exception of Simoes-Lopes (2006), these studies were mainly based on traditional studies of morphometrics. There are no previous comparative studies using non-metric characteristics such as, for example, the comparison of forms or presence and absence of determined characters for this genus. Therefore, this study aims to compare the two species of the genus Sotalia using nonmetric characters.
2. Material and Methods
A total of 149 specimens were analysed from five distinct Brazilian states: Mammal Collection of National Institute for Amazonia Research (INPA), Manaus, Amazonas (AM); Emilio Goeldi Museum (MPEG), Belem, Para (PA); Aquatic Mammals Laboratory (LMA) of the Department of Ecology and Zoology, Federal University of Santa Catarina (UFSC), Florianopolis, Santa Catarina (SC); as well as the Osteological Archive of the Association of Research and Preservation of Aquatic Ecosystems (AQUASIS), Caucaia, Ceara (CE) (Tables 1-4). The INPA collection contains riverine specimens (S. fluviatilis) from the Amazonas State (AM), marine specimens from the coast of the Amapa (AP) and estuarine specimens (S. guianensis) from Para State (PA). The other collections only possess marine specimens from their respective localities. Forty-four specimens of S. fluviatilis and 105 specimens of S. guianensis were analyzed (AP = 24; PA = 02; CE = 41; SC = 38). The marine specimens were divided into 3 large areas: NOR (including specimens from AP and PA), for the specimens from the coast of Amapa and Para States, CE for the specimens off the Ceara coast and SC for specimens from the Santa Catarina coast.
[FIGURE 1 OMITTED]
[FIGURE 2 OMITTED]
[FIGURE 3 OMITTED]
The skulls were compared using non-metric characters, in accordance with Perrin et al. (1982) and two newly proposed characters (Table 5; Figures 1-4). The cervical vertebrae were analyzed according to the presence or absence of cervical ribs.
In order to observe ontogenetic variation, the characters were evaluated by age classes (calf, juvenile, immature and adult) (adapted from Dawbin et al., 1970). Variations between the sexes were not analysed in this study due to the small sample size.
The terminology used for skeletal bones followed Flower (1885), Kraglievich (1937), Lessertieur and Saban (1967), Rommel (1990) and Simoes-Lopes (2006).
Of the 22 non-metric characters analysed, only six were informative for the distinction between the two species.
A high frequency of fenestrae in the occipital region was observed, near the foramen magnum in S. fluviatilis (66%; n = 44). In S. guianensis the percentage of occurrence of fenestrae varied between 31% (specimens from NOR, n = 26), 10 % (CE, n = 41) and 13% (SC, n = 39).
The number of fenestrae near the condyle was also larger in the riverine species, varying from one to four per individual. In both species, these structures were found in all age classes.
In the marine species, the specimens from CE and NOR exhibited one to three fenestrae, while those from SC exhibited only one to two. Fenestrae can occur only on one side (more common in the marine species) or on both sides of the occipital condyle (more common in the riverine species). In newborn and young specimens, other openings in the occipital region (located above the fenestrae) were observed, corresponding to the fontanelles, formed by the union of the exoccipital, parietal and supraoccipital bones (Figure 5).
[FIGURE 4 OMITTED]
In the region of occipital protuberance, in general, the occurrence of fenestrae was less frequent: 4.5% in S. fluviatilis (n = 44), 10% for S. guianensis of CE (n = 41), 5% for specimens from SC (n = 38) and no occurrence for marine specimens from NOR (n = 26). In some specimens of the two species, small fenestrae of irregular contour in the basioccipital were observed. In the marine species, such fenestrae occurred in 2% (n = 41) and 8% (n = 39) of the specimens from CE and SC, respectively. In the riverine species, these fenestrae occurred in 9% (n = 43) of the specimens. These openings were not observed in the marine specimens from NOR.
[FIGURE 5 OMITTED]
[FIGURE 6 OMITTED]
[FIGURE 7 OMITTED]
There was a prevalence of one form of vomer for the marine species, and another form for the riverine species (Figure 6). The wide form (wider in the posterior region) was more frequent in the riverine species, occurring in 57% (n = 37) of specimens, followed by the intermediate form (32%) and the narrow form (11%) (Figure 7). In the marine species, the narrow form was most frequent, occurring in 76% (n = 21) of the specimens from NOR and in 66% (n = 38) of the specimens from CE. The intermediate form of the vomer occurred in 9.5% (n = 21) of the specimens from NOR and in 31.5% (n = 38) of the specimens from CE. This characteristic was added later to the analysis, thus the specimens from SC were not included in the analyses. This characteristic seems to be related with individual variation and not with development.
[FIGURE 8 OMITTED]
The contact, anterior and posterior, between pterygoids exhibited no variation, being separate (gap >1 mm) in 100% of specimens of both species (except for INPA specimen 130 from AP, whose pterygoides had medial contact). In riverine species it was observed that generally there was a greater distance between pterygoids in the posterior portion, forming an inverted "v". Young individuals of marine species seems to present this same greater distance in the posterior portion. This could indicate neoteny in the riverine species, but in order to be able to interpret this variation a more thorough morphometric study is needed.
3.4. Anterior lacerate foramen
The predominant form of anterior lacerate foramen was distinct in the two species (Figures 8 and 9). In S. fluviatilis, the majority of specimens (88%, n = 43) exhibited open/elongated anterior lacerate foramen. In S. guianensis, the majority of the specimens analysed exhibited foramen divided by a projection in the form of a spine: 72% (NOR, n = 25), 77.5% (CE, n = 40) and 98%, (SC, n = 38). This spine projection, which rarely develops in adults of the riverine species, seems to be associated with ontogenetic development in the marine species, leading to the assumption that it is related to neoteny. A more detailed study with a larger number of young and juveniles of both species could provide an answer to this question. In the three marine samples analysed, it was observed that some individual adults exhibited a formation of fusion points between the projection and one side of the lacerate foramen.
3.5. Hypoglossal foramen
The location of hypoglossal foramen next to the jugular notch was considerably higher in S. guianensis: 88% (NOR, n = 25), 95% (CE, n = 41) and 98% (SC, n = 39). In this species, this foramen is generally visible in the ventral view, externally displaced to the jugular notch. Conversely, in the riverine species, the majority of specimens (87%, n = 45) exhibited this foramen internally displaced to the jugular notch, not easily observed in the ventral view (Figures 10 and 11). It is worth noting, however, that variation exists in the proximity of this foramen to the jugular notch in both species, where some individuals exhibit a displaced foramen, being either separated or together with the notch. This characteristic doesn't seem to be related with development.
[FIGURE 9 OMITTED]
[FIGURE 10 OMITTED]
3.6. Cervical vertebrae
In the cervical vertebrae, projections on the seventh cervical vertebrae (Ce7) associated with the transversal canal (= vertebrarterial canals), are called pleuroapophiseal plates or cervical ribs (Figures 12). The occurrence of these structures was higher in S. fluviatilis (87%; n = 31) than in S. guianensis from CE (9%, n = 23) and from SC (19%, n = 32). Furthermore, the size of the ribs is proportionally smaller in the riverine species than in the marine species. In S. guianensis, the cervical ribs were generally observed only on one side (right or left), while in S. fluviatilis they were observed on both sides. The UFSC specimen 1117 exhibited this structure on the on the right side of the third cervical vertebra ([Ce.sub.3]). The cervical ribs were observed in all age classes.
[FIGURE 11 OMITTED]
[FIGURE 12 OMITTED]
The presence of fenestrae commonly observed in the occipital region, near the condyles of Sotalia fluviatilis was also recorded in juveniles and adults of Pontoporia blainvillei (Gervais and d'Orbigny, 1844) (Pinedo,1991). However, in Pontoporia, the number of fenestrae was greater than that observed for the genus Sotalia.
In the genus Sotalia, the occurrence of fenestrae next to protuberances of the occipital region was low compared with the region next to the condyles. In the basioccipital, the presence of fenestrae was less frequent in immature specimens than in mature specimens. In Pontoporia blainvillei and in Stenella the occurrence of this structure was rare and occasional, respectively (Pinedo, 1991; Perrin et al., 1982).
Considering that the fenestrae observed next to the condyles in S. fluviatilis do not have the same origin as the fontanelles present in newborn individuals, given their different location, the origin and function of these fenestrae are not clear.
The cranial floor is not generally included in morphologic studies and revealed interesting results. SimoesLopes (2006), analysing specimens of S. guianensis in the southern region, observed that the laminar posterior process of the vomer is narrower than the lamelar pterygoid processes.
In the same study, the author found the converse in S. fluviatilis--where the vomer is broader and the lamelar pterygoid processes narrower. In the present work we verified that this characteristic described by Simoes-Lopes (2006) was present in the majority of the marine specimens analysed. However, in the samples from CE and AP, we observed that some specimens also possessed a broad vomer, similar to the riverine species, herein called the "wide form". Apparently, this characteristic can be used to distinguish the two species, but it is important to note that a small percentage of marine specimens possess a broad vomer just as some riverine specimens possess a narrow vomer. Thus, the use of this characteristic should be considered in combination to others when separating the species.
In relation to the posterior alignment of the vomer, the arrangement anterior to the lamelars pterygoid processes was observed in 100% of the cases for the marine species. In the riverine species (n = 39), 18% were observed with the posterior edge of the vomer aligned with the pterygoids, while in another 18% the posterior edge of the vomer extended beyond the pterygoides. Dawbin et al. (1970) attribute the alignment of the vomer in relation to the posterior pterygoid processes to age. For these authors, in sub-adults Peponocephala electra (Gray, 1846) the vomer extends to the level of the sutures between the pterygoides and basioccipital and in adults, the vomer extends beyond the adjacent pterygoides. This pattern was not observed in the current study, since all adults of S. guianensis were observed with the posterior suture of the vomer anterior to the pterygoides. Moreover, the variation observed in the riverine species does not appear to be related to ontogenetic development, but rather to individual variation.
The pterygoides were found to be medially separated by a projection in the tip of the palatines in all specimens, corroborating the data found in the literature (van Beneden, 1875; Flower, 1885; Miranda-Ribeiro, 1936, da Silva and Best, 1994; 1996; Avila et al., 2002; SimoesLopes, 2006). The variation in the form of the posterior projection of the left pterygoide was very subtle between the two species.
4.4. Anterior lacerate foramen
The anterior lacerate foramen is formed by two foramens (the optic foramen and the orbitorotundum foramen). These two structures are divided by a "wall" (Yamagiwa, et al., 1999) here called a spike-shaped projection. In S. guianensis, the majority of the adult specimens (between 72 and 98%) exhibited this projection between the optic and the orbitorotundum foramen. On the other hand, the narrow form was only observed in adults, suggesting that with time, this spiny projection fused with one side of the lacerated foramen (as observed in some marine specimens). In S. fluviatilis, in contrast, the absence of this projection was more common (88%), and could indicate neoteny.
4.5. Hypoglossal foramen
The location of the hypoglossal foramen varied between the two species. In S. guianensis the hypoglossal foramen generally meets between the crest of the basioccipital and the paraoccipital process, more precisely in the jugular notch as it occurs in other species of marine Delphinidae, for example, Grampus griseus (Cuvier, 1812) (Yamagiwa et al., 1999) and Tursiops truncatus (Montagu, 1821) (Rommel, 1990). In contrast, the hypoglossal foramen in S. fluviatilis, in the majority of cases, was found to be internally displaced.
4.6. Cervical vertebrae
The occurrence of cervical ribs was higher (87%) in the riverine species. The presence of pleuroapophiseal plates was initially suggested for some groups of mammals, especially monotremes and marsupials (Lessertisseur and Saban, 1967). Unilateral or bilateral processes in the cervical vertebrae are common in some groups of mammals (including Homo), and the costal rudiments are associated with the vertebral or vertebrarterial foramens (Lessertisseur and Saban, 1967). These authors also mention their presence in marine mammals as Orcinus orca (Linnaeus, 1758), Tursiops truncatus and Balaenoptera sp. Such processes have been considered serially homologous to the cervical ribs, also appearing in the literature as costal plates or pleuroapophiseal plates (Flower and Lyddeker, 1891). The presence of cervical ribs is an intriguing characteristic in comparative anatomy, as these structures are typically observed in reptiles (Paula Couto, 1979; Ferigolo, 1987). In S. guianensis, these structures have already been reported in about 22.5% (n = 31) of the specimens of the southern region (Fettuccia and Simoes-Lopes, 2004). In this work, considering a larger sample, the observed frequency of cervical ribs in the specimens from SC was 19% (n = 33), and of 9% (n = 23) from CE. Cervical ribs in mammals are examples of atavism (reappearance of an extinct character, common to ancestral lineages that rarely occur in current populations). Other cases of atavism are described in the literature as the occurrence of vestigial posterior members in whales and extra-numeric teeth in bats and sea lions (Bejder and Hall, 2002; Rui and Drehmer, 2004 and Drehmer et al., 2004). According to Hall (1984), there are four basic criteria for the recognition of an atavism: 1) persistence of the characteristic in adult life; 2) absence of this characteristic in the parents or recent ancestors; 3) occurrence in one or a few individuals within a population; and 4) similarity or identity with the same character exhibited by all the members of the ancestral population. Moreover, if the incidence of the character is still relatively high in a population, it is considered a polymorphism (Hall, 1984). Thus, considering the high occurrence of cervical ribs in specimens of the riverine species, these structures do not appear to be atavistic, suggesting the need for a more detailed study with a more representative sample number for a more consistent conclusion.
Acknowledgements--The authors would like to thank Angel Enzo Crovetto, Cesar Drehmer, Fernando Rosas, Lena Geise and two anonymous referees for their helpful suggestions on improving the manuscript. We would also like to thank Nina Best for the English review. Special thanks to the Museu Paraense Emilio Goeldi (MPEG) and Associacao de Pesquisa e Preservacao de Ecossistemas Aquaticos (AQUASIS). This work was supported by grants from CNPq and IEB.
Received December 7, 2007--Accepted August 27, 2008--Distributed August 31, 2009
ALVES-JUNIOR, TT. and MONTEIRO-NETO, C., 1999. Caracterizacao morfologica e morfometrica craniana do botocinza, Sotalia fluviatilis Gervais, 1953, da Costa do Ceara, Brasil. Arquivos de Ciencias do Mar, no. 32, p. 89-101.
AVILA, FJC., ALVES-JUNIOR, TT., PARENTE, CL., VAZ, LAL. and MONTEIRO-NETO, C., 2002. Osteologia do botocinza, Sotalia fluviatilis Gervais, 1853, da Costa do Estado do Ceara, Brasil. Arquivos de Ciencias do Mar, no. 35, p. 145-155.
BEJDER, L. and HALL, BK., 2002. Limbs in whales and limblessness in other vertebrates: mechanisms of evolutionary and developmental transformation and loss. Evolution and Development, vol. 4, no. 6, p. 445-458.
VAN BENEDEN, E., 1875. Memoire sur un dauphin nouveau de la Baie de Rio de Janeiro, designe sous le nom de Sotalia brasiliensis. Memmoires de l'Academie Royale de Sciences Belgique, vol. 41, p. 2-44.
BOROBIA, M., 1989. Distribution and morphometrics of South American dolphins of the genus Sotalia. Montreal: McDonald College of McGill University. 81 p. [Master's thesis].
BOROBIA, M., SICILIANO, S., LODI, L. and HOEK, W., 1991. Distribution of the South American dolphin Sotalia fluviatilis. Canadian Journal Zoology, no.69, p. 1025-1039. CASINOS, A., BISBAL, F. and BOHER, S., 1981. Sobre tres exemplares de Sotalia fluviatilis del Lago Maracaibo (Venezuela) (Cetacea, Delphinidae). Proceedings of the Departament of Zoology, no. 7, p. 93-96.
CUNHA, HA., DA SILVA, VMF., LAILSON-BRITO Jr, J., SANTOS, MCO., FLORES, PAC., MARTIN, AR. et al., 2005. Riverine and marine ecotypes of Sotalia dolphins are different species. Marine Biology, vol. 148, no. 2, p. 449-457.
CABALLERO, S., TRUJILLO, F., VIANNA, JA., BARRIOSGARRIDO, H., MONTIEL, MG., BELTRAN-PEDREROS, S. et al., 2007. Taxonomic status of the genus Sotalia: species level ranking for "tucuxi" (Sotalia fluviatilis) and "costero" (Sotalia guianensis) dolphins. Marine Mammal Science, vol. 23, no. 2, p. 358-386.
DA SILVA, VMF. and BEST, RC., 1994. Tucuxi Sotalia fluviatilis (Gervais, 1853). In RIDGWAY, SH., HARRISON, SR. (Eds). Handbook of Marine Mammals. London: Academic Press. p. 43-69.
--, 1996. Sotalia fluviatilis. Mammalian Species, no. 527, p. 1-7.
DAWBIN, WH., NOBLE, BA. and FRASER, FC., 1970. Observations on the electra dolphin, Peponocephala electra. Bulletin of the British Museum (Natural History), vol. 20, no. 6, p. 173-201.
DREHMER, CJ., FABIAN, ME. and MENEGHETI, JO., 2004. Dental anomalies in the Atantic population of South American sea lion, Otaria byronia (Pinnipedia, Otariidae): evolutionary implications and ecological approach. LAJAM, vol. 3, no. 1, p. 7-18.
FERIGOLO, J., 1987. Anatomia comparada, paleontologia e paleopatologia de vertebrados. Paula-Coutiana, no. 1, p. 105-127.
FETTUCCIA, DC. and SIMOES-LOPES, PC., 2004. Morfologia da coluna vertebral do boto-cinza, Sotalia guianensis (Cetacea, Delphinidae). Biotemas, vol. 17, no. 2, p. 125-148.
FLOWER, WH., 1885. An Introduction to the Osteology of the Mammalia. 3 ed. London: Macmillan & Co. 344 p.
FLOWER, WH. and LIDEKKER, R., 1891. An introdution to the study of Mammals living and extinct. New York: Arno Press. 763 p. (Reprint edition 1978).
HALL, BK., 1984. Developmental echanisms underlying the formation of atavisms. Biological Reviews of the Cambridge Philosophical Society, no. 78, p. 409-433.
KRAGLIEVICH, L., 1937. Manual de Paleontologia Rio Platense Comparada de los Mamiferos. Montevideo: Ed. Siglo Ilustrado. 190 p.
LESSERTIEUR, J. and SABAN, R., 1967. Squelette Axial. In GRASSE, PP. (Ed.). Traite de Zoologie, Mammiferes: Teguments et Squelettes. Paris: Masson et Cie. Editeurs. p. 585-708.
MENEZES, ME. and SIMOES-LOPES, PC., 1996. Osteologia e morfologia da aleta peitoral da forma marinha de Sotalia fluviatilis (Cetacea-Delphinidae) no litoral do Brasil. Estudos de Biologia, vol. 4, no. 40, p. 23-31.
MIRANDA-RIBEIRO, A., 1936. Notas cetologicas dos generos Steno, Sotalia e Stenopontistes. Boletim do Museu Nacional do Rio de Janeiro, no. 12, p. 3-23.
MONTEIRO-FILHO, ELA., MONTEIRO, LR. and REIS, SF., 2002. Skull shape and divergence in dolphins of the genus Sotalia: a tridimensional morphometric analysis. Journal of Mammalogy, vol. 83, no. 1, p. 125-134.
PAULA COUTO, C., 1979. Tratado de Paleomastozoologia. Rio de Janeiro: Academia Brasileira de Ciencias. 590 p.
PERRIN, WF., YABLOKOV, AV. and CASS, VL., 1982. Preliminary report on the use of non-metrical skull characters to discriminate populations of pelagic dolphins. E.U.A.: National Marine Fisheries Services. 32 p.
PINEDO, MC., 1991. Development and variation of the franciscana, (Pontoporia blainvillei), Santa Cruz. California: University of California. 406 p. [PhD. Thesis].
ROMMEL, SA., 1990. Osteology of the Bottlenose Dolphin. In LEATHERWOOD, S.; REEVES, R. (Eds.). The Bottlenose Dolphin. San Diego: Academic Press. p. 29-49.
RUI, AM. and DREHMER, CJ., 2004. Anomalias e variacoes na formula dentaria em morcegos do genero Artibeus Leach (Chiroptera, Phyllostomidae). Revista Brasileira de Zoologia, vol. 21, no. 3, p. 639-648.
SIMOES-LOPES, PC., 1988. Ocorrencia de uma populacao de Sotalia fluviatilis (Gervais, 1853) (Cetacea, Delphinidae) no limite sul de sua distribuicao, Santa Catarina, Brasil. Biotemas, vol. 1, no. 1, p. 57-62.
--, 2006. Morfologia do sincranio do Boto-cinza, Sotalia guianensis (P.J. van Beneden, 1864) (Cetacea, Delphinidae). Revista Brasileira de Zoologia, vol. 23, no. 3, p. 652-660.
YAMAGIWA, D., ENDO, H., NAKANISHI, I., KUSANAGI, A., KUROHMARU, M. and HAYASHI, Y., 1999. Anatomy of the cranial nerve foramina in the Risso's dolphin (Grampus griseus). Annals of Anatomy, vol. 181, p. 293-297.
Fettuccia, DC. (a)* da Silva, VMF. (a) and Simoes-Lopes, PC. (b)
(a) Laboratorio de Mamiferos Aquaticos--INPA, Av. Andre Araujo, 2936, Aleixo, CEP 69060-001, Manaus, AM, Brazil
(b) Laboratorio de Mamiferos Aquaticos--LAMAQ, Departamento de Ecologia e Zoologia, CCB, Universidade Federal de Santa Catarina--UFSC, CP 5102, CEP 88040-970, Florianopolis, SC, Brazil
* e-mail: email@example.com
Table 1. List of Sotalia fluviatilis analysed from the northern region (Amazon State, Brazil), deposited at INPA's mammals collection. F - female, M - male, I - indeterminate gender. N = 44. Collection number Sex Age class Locality INPA 005 I adult Japura River INPA 007 I adult Tefe Lake INPA 008 I adult Tefe Lake INPA 009 M juvenile Negro River INPA 015 F calf Japura River INPA 016 I adult Japura River INPA 017 M adult Japura River INPA 018 I calf Japura River INPA 020 I adult Japura River INPA 024 I adult Japura River INPA 026 M juvenile Purus River INPA 029 F juvenile Tefe Lake INPA 038 F calf Japura River INPA 039 M immature Japura River INPA 040 F adult Amana Lake INPA 041 M adult Negro River/Anavilhanas INPA 043 M juvenile Japura River INPA 047 M adult Jurua River INPA 050 F immature Amana Lake INPA 051 M calf Amazonas River INPA 052 M adult Amazonas River INPA 053 F adult Amazonas River INPA 054 M calf Amazonas River INPA 055 I adult Amazonas River INPA 056 F adult Amazonas River INPA 057 F adult Marchantaria, Solimoes River INPA 059 M juvenile Marchantaria, Solimoes River INPA 060 M juvenile Tefe Lake INPA 062 F adult Japura River INPA 065 M calf Japura River INPA 067 I adult Negro River/ INPA 069 F adult Anavilhanas INPA 071 F adult Japura River INPA 072 I adult Para River INPA 073 F adult Purus River INPA 074 M adult Purus River INPA 080 M calf Catalao, Negro River INPA 081 M juvenile Cabaliana Lake, Manacapuru INPA 082 F calf Tapajos River INPA 093 M adult Tocantis River/Tucurui INPA 097 F juvenile Negro River INPA 113 M adult Solimoes River INPA 149 I adult Coari Grande River INPA 151 I adult Coari Grande River Table 2. List of Sotalia guianensis analyzed from northern region (Amapa and Para States, Brazil), deposited at INPA and MPEG mammals collections, respectively. F - female, M - male, I - indefinite gender. N = 26. Collection number Sex Age class Locality INPA 120 M juvenile Amazonas Estuary INPA 121 M juvenile Amazonas Estuary INPA 122 M juvenile Amazonas Estuary INPA 123 M adult North of Amapa INPA 124 F juvenile North of Amapa INPA 125 F juvenile Amazonas Estuary INPA 126 M juvenile North of Amapa INPA 127 M calf North of Amapa INPA 128 M calf North of Amapa INPA 129 M adult North of Amapa INPA 130 F juvenile North of Amapa INPA 131 F calf Amazonas Estuary INPA 132 F calf Amazonas Estuary INPA 133 M juvenile North of Amapa INPA 134 F adult North of Amapa INPA 135 F calf North of Amapa INPA 136 M calf North of Amapa INPA 137 M calf North of Amapa INPA 138 F juvenile North of Amapa INPA 139 F juvenile North of Amapa INPA 140 M juvenile North of Amapa INPA 141 F adult North of Amapa INPA 142 F adult North of Amapa INPA 143 F adult North of Amapa MPEG 24548 I adult Marajo Island MPEG 10945 F juvenile Marajo Island Table 3. List of Sotalia guianensis analysed from the Northeast region (Ceara state, Brazil), deposited at AQUASIS's collection. F - female, M - male, I - indeterminate gender. N = 41. Collection number Sex Age class Locality Aq 002 M adult Caucaia Aq 004 I juvenile Fortaleza Aq 012 I adult Fortaleza Aq 013 M adult Fortaleza Aq 023 M adult Caucaia Aq 026 I adult Caucaia Aq 036 F adult Fortaleza Aq 038 M adult Caucaia Aq 039 I adult Sao G. Amarante Aq 040 I calf Sao G. Amarante Aq 041 I immature Fortaleza Aq 042 M adult Fortaleza Aq 058 F adult Fortaleza Aq 071 I adult Cascavel Aq 084 M adult Fortaleza Aq 132 M juvenile Sao G. Amarante Aq 134 M adult Fortaleza Aq 139 I adult Itapipoca Aq 159 I adult Fortaleza Aq 184 F adult Fortaleza Aq 196 I immature Sao G. Amarante Aq 210 F adult Paracuru Aq 212 F adult Fortaleza Aq 213 M calf Fortaleza Aq 214 F juvenile Caucaia Aq 215 I adult Sao G. Amarante Aq 218 M juvenile Sao G. Amarante Aq 222 F adult Fortaleza Aq 231 M adult Caucaia Aq 232 M adult Fortaleza Aq 234 M adult Caucaia Aq 236 I adult Sao G. Amarante Aq 239 M adult Fortaleza Aq 240 I immature Paraipaba Aq 241 I adult Caucaia Aq 247 F adult Fortaleza Aq 250 M calf Paraipaba Aq 251 I adult Traire Aq 253 M adult Fortaleza Aq 259 M adult Fortaleza Aq 262 I adult Bitupita - - - - Table 4. List of Sotalia guianensis analysed from the Southern region (Santa Catarina state, Brazil), deposited at LAMAq's collection (UFSC). F - female, M - male, I - indeterminate gender. N = 38. Collection number Sex Age class Locality UFSC1010 I juvenile Daniela Beach UFSC1073 I adult Biguacu UFSC1079 F adult Beira Mar Norte UFSC1082 I adult Beira Mar Norte UFSC1083 M adult Beira Mar Norte UFSC1104 F immature Beira Mar Norte UFSC1108 M adult Beira Mar Norte UFSC1117 I adult Biguacu UFSC1130 F adult G. Celso Ramos UFSC1174 M calf Sambaqui UFSC1175 M adult Sao F. do Sul UFSC1176 I adult Costeira UFSC1178 M juvenile Sambaqui UFSC1179 M juvenile Beira Mar Norte UFSC1180 F adult Cacupe UFSC1203 F adult Anhatomirim UFSC1208 F adult Estreito UFSC1218 F adult Curtume Beach UFSC1219 F adult Costeira UFSC1222 M immature Estreito UFSC1223 M calf Anhatomirim Island UFSC1226 M adult G. Celso Ramos UFSC1236 F calf Sambaqui UFSC1245 I juvenile Sao F. do Sul UFSC1247 I adult Cacupe UFSC1253 M juvenile Beira Mar Norte UFSC1266 M immature Biguacu UFSC1268 F adult Biguacu UFSC1289 F adult G. Celso Ramos UFSC1291 M adult G. Celso Ramos UFSC1296 M juvenile Anhatomirim UFSC1297 M adult G. Celso Ramos UFSC1302 I adult Itapoa UFSC1307 M juvenile Daniela Beach UFSC1311 I immature Sao F. do Sul UFSC1312 M adult Estreito UFSC1321 F adult Itaguacu Beach UFSC1327 M calf Beira Mar Norte Table 5. List of non-metric characters analysed in skulls and cervical vertebrae from specimens of the genus Sotalia. Adapted from Perrin et al. (1982) and two new proposed characters (4a e 4g). NI: not illustrated. Figure character and character condition 1 a. Asymmetry of position of the two anterior most large maxillary foramina: 1- symmetrical; 2- left foramen more anteriorly placed; right foramen more anterior. b. Number of small foramina in the maxillary anterior to the anterior-most of the three large foramina. c. Number of foramina in the maxillary behind a line at the level of the anterior edge of the external nares and perpendicular to the long axis of the skull. d. Contact between maxillary and occipital, at point where occipital crest intersects margin of temporal fossa: 1- contact (or space of <1 mm); 2- no contact. e. Contact between premaxillary and nasal, on right side: 1- contact (or space of <1 mm); 2- no contact. f. Asymmetry of position of the two premaxillary foramina: 1- symmetrical; 2- left foramen more anteriorly placed; right foramen more anterior g. Development of dorsal mesethmoid spine at the anterior margin of external nares, between angles of premaxillaries: 1- elevation of the ossified portion of the mesethmoid to, or near to the level of the dorsal surfaces of the premaxillaries; 2- no such elevation. 2 Composition of the anteorbital process, in lateral view, of the left side: 1- formed by lacrimal; 2- formed by lacrimal and frontal; 3- formed lacrimal and maxillary. 3 a. Medial occipital ridge, projecting above level of the occipital swellings at mid-height: 1- present; 2- absent, or not projecting above swellings. b. Accessory foramen above foramen magnum: 1- present; 2- absent. c. Clear notch in upper margin of foramen magnum: 1- present; 2- absent. d. Number of fenestrations in occipital, near foramen magnum and in exoccipital region. e. Number of fenestrations in region of occipital swellings. 4 a. Shape of the vomer among posterior process of the pterygoids: 1- wide; 2- intermediate; 3- narrow. b. Anterior contact between pterygoid hamuli: 1- open (gap > 1 mm); 2- closed. b. Posterior contact between pterygoid hamuli: 1- open (gap > 1 mm); 2- closed. d. Shape of posterior projection of left pterygoid hamulus: 1- longer than wide (y > x); 2- wider than long, or equal (x > y). e- Vomer's posterior alignment in relation to pterygoids's lamellar process: 1- anterior; 2- aligned; 3- posterior. f- Number of fenestrations in region of basoccipital. g- Shape of the anterior lacerate foramen (right): 1- open; 2- with projection spine form; 3- narrow. h- Visibility, in ventro-occipital view of mesially directed hypogossal foramen between basoccipital and exoccipital process (jugular notch): 1- visible; 2- not visible. NI Cervical rib: 1- present; 2- absent.
|Printer friendly Cite/link Email Feedback|
|Author:||Fettuccia, D.C.; da Silva, V.M.F.; Simoes-Lopes, P.C.|
|Publication:||Brazilian Journal of Biology|
|Date:||Aug 1, 2009|
|Previous Article:||Flow cytometry as a tool in the evaluation of blood leukocyte function in Chelonia mydas (Linnaeus, 1758) (Testudines, Cheloniidae)/A citometria de...|
|Next Article:||Analysis of the microstructure of Xenodontinae snake scales associated with different habitat occupation strategies/Analise da microestrutura de...|