, and Sergestidae ( Crustacea : Decapoda ) : Records of native species from the states of Amapá and Pará , Brazil , with maps of geographic distribution

and Nematopalaemon schmitti (Holthuis, 1950) from both states; and Pileggi et al. (2013) informed a number of records for several species from both states as well. The occurrence of freshwater shrimps in these two states can also be verified in check lists and faunistic papers (Coelho and Ramos-Porto 1985; Barros and Silva 1997; Ramos-Porto & Coelho, 1998; Barros and Pimentel 2001; Vieira 2003, 2008; Magalhães and Pereira 2007; Cavalcante et al. 2012) or in several papers dealing with population dynamics (Odinetz Collart 1991, Silva et al. 2005, Bentes et al. 2011, Freire et al. 2012a), growth (Silva et al. 2007), and fisheries (Odinetz Collart 1987; Silva et al. 2002a, b, 2005; Lucena-Frédou et al. 2010; Freire et al. 2012b). Despite the previous records, there is still much unpublished information about the distribution of freshwater shrimps in carcinological collections of the three main institutions in northern Brazilian. The purpose of this paper is to list the records of freshwater species of Euryrhynchidae, Palaemonidae and Sergestidae from the states of Amapá and Pará housed at the Instituto de Pesquisas Científicas e Tecnológicas do Amapá (Macapá), Instituto Nacional de Pesquisas da Amazônia (Manaus), and Museu Paraense Emílio Goeldi (Belém), so that this information can be useful for taxonomic and zoogeographic studies as well as conservation assessments.


Discussion
The distribution of freshwater shrimps from Amapá and Pará is well known, but its diversity is likely to be underestimated, since faunistic surveys are scarce and vast areas are still poorly explored. For this same reason, the distribution of many species might be larger then informed by the records presented in this paper (Figures  1-9).
Macrobrachium brasiliense is widespread, occurring in coastal rivers of Amapá and in most of the State of Pará. M. nattereri has also a wide distribution, occurring from the western to the eastern part of the State of Pará; the species was not recorded in the State of Amapá. Macrobrachium amazonicum and M. surinamicum have roughly the same distribution pattern, both occuring in the eastern and southeastern portions of the States of Amapá and Pará, as well as in the northeast portion of Pará, with records in the Pará River and the Tocantins and Guama Rivers. The distribution of M. amazonicum also covers the western portion of the State of Pará, occurring in the Xingu River. The distribution of the M. jelskii is similar to that of M. amazonicum, with the records being distributed mainly along the Amazon River, as well as in the coastal river basins of Amapá and Pará.
Acetes marinus, Macrobrachium carcinus, M. acanthurus, M. olfersii and Palaemon pandaliformis have a more restricted, almost punctual distributions, which cover coastal basins of the States of Amapá and Pará. M. olfersii is widely distributed in the Americas (Bowles 2000) and the data obtained in this work confirm its occurrence in the State of Amapá. However, its occurrence in Pará could not be confirmed, probably due to lack of collections. M. carcinus occurs in the lower portion of both the Amazonas and Tocantins rivers.
Palaemon mercedae, Pseudopalaemon chryseus, P. amazonensis, and the three species of Euryrhynchus occur in less extensive areas, usually associated with submerged leaf litter habitat of the acidic, nutrient-poor, black and clear water river systems that drain the Guyana and central Brazil shields.
The genus Euryrhynchus has three representatives in the Amazon basin: E. amazoniensis, E. burchelli, and E. wrzesniowskii. The first species was thought to be restricted to the central Amazon region, but García-Dávila and Magalhães (2004) extended the range to the western Amazon, in the Peruvian province of Requena, and Vieira (2003; recorded it from the State of Amapá. E. burchelli, previously reported from Pará by Tiefenbacher (1978) and Holthuis (1951;1966), is known from the west and northeast portions of this state; the species was also reported from the eastern Amapá (Vieira 2003). The distribution of E. wrzesniowskii encompasses Guyana and Suriname (Tiefenbacher 1978), and the central , and eastern (Vieira 2003; Amazon basin. In the present study, its distribution range is extended to northeastern Pará. Three species of the genus Palaemon are found in the inland waters of the Amazon basin: Palaemon ivonicus, P. carteri, and P. mercedae, but only the last two have been recorded in the eastern Amazon region. In Amapá, P. carteri is distributed in the northeast and southeast parts of the State of Amapá, while in the State of Pará it ranges from the western portion, in the Trombetas River, to the northeastern portion of the state. P. mercedae was described from Venezuela  and has subsequently been found in Central Amazon (Magalhães 1988). Pileggi et al. (2013) firstly reported the occurence of this species in Pará, in the Tapajós River Basin.
The genus Pseudopalemon is endemic to South America  and six species are known from the Amazon basin, but only two have been found in eastern Amazon.  listed P. amazonensis for Pará, but did not offer documented data on its occurrence. The records presented herein show that the species is found from the Caxiuanã Bay to northeastern Pará, inhabiting black-water forest streams. P. chryseus has been recorded from the southeastern portion of Amapá (Vieira 2003;Pileggi et al. 2013), and from Trombetas River to the lower Amazon basin, in Pará .
The two freshwater species of Sergestidae occur in eastern Amazon region. A. marinus is mainly found in areas influenced by oligohaline waters and its range is restricted to the lower Amazon and Tocantins Rivers, and coastal rivers of the State of Amapá (Omori 1975;D'Incao and Martins 2000;present paper). A. paraguayensis has a very wide distribution in South America, ranging from the Orinoco and Amazon basins to the lower Paraná River basin . It occurs in the Amazon River and its main tributaries in Pará (Trombetas, Tapajós, Xingu, Tocantins, and Pará Rivers), but has not yet been recorded in Amapá.
Additionally, two exotic species from the Indo-Pacific region have also been reported from Pará. Barros and Silva (1997) recorded Macrobrachium rosenbergii (De Man, 1879) from the surroundings of Belém and Bragança. A study using molecular analysis made by Iketani et al. (2011) determined that the species introduced in the coastal areas of Pará was actually M. dacqueti (Sunier, 1925), but the name M. rosenbergii must be kept (Wovor and Ng 2008;ICZN 2010). Maciel et al. (2011) found Macrobrachium equidens (Dana, 1852) from the Taici Creek, a tidal channel that connects the Caeté and Taperaçu Rivers, near Brangança, northeastern Pará.