The Axiidea in the Museum of Oceanography Petr ô nio Alves Coelho, Recife, Brazil, with Some Remarks on the Biology of the Species

: Axiidea housed in the collection of the Museu de Oceanograﬁa Prof. Petr ô nio Alves Coelho, Universidade Federal de Pernambuco (MOUFPE) were studied. This collection contains 66% of the total diversity of axiideans recorded from the continental shelf of the Brazilian coast. The species are listed by family and genus as follows: Axiidea


Introduction
The infraorder Axiidea de Saint Laurent, 1979 [1] encompasses the so-called ghost shrimps, mud lobsters or burrowing shrimps [2][3][4].This infraorder represents one clade of marine decapods with a body form completely adapted for a fossorial lifestyle who are an important benthic component of sandy or muddy intertidal, shallow subtidal and deep-sea habitats worldwide [3,5,6].
Burrowing shrimps are known for constructing burrows of different shapes and depths [7] and for playing a significant role in shaping community structure [8].Bioturbation produced by these species, i.e., the activity of water and sediment expulsion from its galleries, contributes to the suspension of organic matter and nitrogen fixation and increases food availability to other trophic levels [9,10].
Axiidean shrimps constitute an important component of the Brazilian benthic communities [11,12].The axiidean fauna of Brazil has been summarized (as Thalassinidea) by Coelho [13], de Melo [14] and, recently (as Axiidea), by Hernáez et al. [12].The latter work listed 35 species across seven families [12].This study provides a comprehensive review of the Axiidea deposited in the zoological collection of the 'Museu de Oceanografia Prof. Petrônio Alves Coelho (MOUFPE)' of the northeastern region of Brazil.With more than 15,000 lots of crustaceans, this collection contains the largest holdings of Axiidea in their respective geographic area.The results of this revision are presented in this paper.

Materials and Methods
Material of Axiidea deposited in the MOUFPE collection primarily originates from a series of oceanographic expeditions conducted between 1965 and 1978 by Petrônio Alves Coelho.These collections were made on the continental shelf and slope off the coast of at a depth of between 75 and 77 m.There are no other reports of this species on the Brazilian coast.
In Brazil, C. nodulosus has been reported as C. abelei from the continental shelf depths of between 40 and 270 m and from the Vitória-Trindade Seamount Chain at depths of between 48 and 81 m (see [27] and present study).The specimen of C. nodulosus from Brazil is characterized by having a rostrum short and triangular, not reaching the cornea; a cervical groove distinct; an antennular peduncle not overreaching antennal penultimate article; uropodal exopod with transverse suture and a telson subtriangular; and narrowing distally, among other characters.Several lots of C. abelei are registered in the database of MOUFPE collection (lots: 8612, 8613, 8614, 12602, 12829, 12940).Unfortunately, all of these batches were found to be missing at the time of this review.Remarks.Manaxius angulatus is endemic to Brazil.This species was originally described as Calastacus angulatus by Coelho [23] and then transferred to Manaxius by Sakai [20].Manaxius angulatus is characterized by having the fingers of the chelipeds shorter than the palm and the pleura 2-5 triangular ventrally (fig.8b in [19]).In the MOUFPE collection, there is only one specimen (holotype) of this species deposited.Type locality.Off Boca Prieta, Puerto Rico, 15.5 m, coral and sand [30].

Genus
Remarks.Paraxiopsis defensus (Rathbun, 1901 [30]) was described based on a female specimen from Boca Prieta, Puerto Rico.After its discovery, this species has been recorded in the Dominican Republic (Barahona Harbour [31]) and Brazil (Pernambuco and Bahia, northeastern region, present study).Morphology of P. defensus is characterized by having three to five pleura rounded ventrally [20].Two specimens of this species are deposited in the MOUFPE collection.Both specimens examined in the MOUFPE are in good condition; both were collected in the northeastern region of Brazil.

Paraxiopsis vicina (Coelho and Ramos-Porto, 1991) [19]
Material-Brazil.Holotype, male, cl 7.9 mm, 2.225 Remarks.Paraxiopsis vicina is endemic to Brazil.This species is only known from the type locality (continental shelf of Ceara).Paraxiopsis vicina differs from other congeneric species in that in this species, the male P1 palm is distinctly tuberculate on the dorsal margin, bearing a tuberculate plate on the ventral margin [19,20,32].
Family Callianassidae Dana, 1852 [33] Genus Cheramoides Sakai, 2011 [20] Cheramoides aff.marginata (Rathbun, 1901) [30] Material-Brazil.Female, major cheliped and abdomen missing, cl: 5.0 mm, station GM 211, 4.458 • N, 50.0.25Remarks.The record of Cheramoides marginata from Brazilian waters in the literature is highly questionable.While several studies previously reported the presence of this species in deeper areas on the continental shelf and slope between Amapá and Rio de Janeiro (see [13][14][15]), all of these records were undertaken without access to comparative materials from the Puerto Rican-type locality.Specimens of C. marginata herein examined disagree in some points from illustrations of C. marginata available in the literature (see [30,34,35]).In the specimens from Brazil, the rostrum exceeds eyestalks (Figure 1A), whereas in C. marginata from Puerto Rico, it is shorter than eyestalks (cf.fig.16d in [34]).Also, the two populations can also be separated from each other by the different proportions in length of the antennular peduncle to the antennal peduncle, which are slightly shorter in Brazilian specimens (Figure 1A) but much shorter in C. marginata from Puerto Rico (cf.fig.16d in [34]).These observations suggest the need for a future comparative study between the specimens identified as C. marginata from Brazil and the type material of this species from Puerto Rico.
Remarks.Callichirus corruptus is one of the most common species of medium-grain sandy beaches along the Brazilian coast [37].Until recently, Brazilian populations of Callichirus were assigned to C. major.Today, both species, geographically separated, are recognized as valid and distinct (see [37]).Callichirus corruptus is restricted to the Brazilian coast (between Pará and Santa Catarina), whereas C. major is from North Carolina down to Florida [37].
Remarks.The taxonomic history of C. hartmeyeri is complex.In 1924, the German zoologist Heinrich Balss identified a callianassid from Kingston (Jamaica), with Callianassa grandimana (Gibbes, 1850) (as Glypturus grandimanus) (see [40]).Subsequently, Schmitt [39], in his review of North American callianassids, recognized the existence of significant differences between Balss's species and C. grandimana and proposed the name Callianassa hartmeyeri for Glypturus grandimanus sensu Balss, 1924 [40].More than 50 years later, Manning [40] stated that the identity of C. hartmeyeri remains uncertain because there is no consensus among researchers regarding the identity of the material collected by Balss and assigned to Glypturus grandimanus.Despite the lack of consensus, C. hartmeyeri is considered a valid species, and together with Corallianassa longiventris A. Milne Edwards, 1870, constitute the two species of the genus recorded for the western Atlantic (see [41]).In Brazil, C. hartmeyeri was recorded in Alagoas by Coelho [13].The label on the only specimen (a male specimen) of C. hartmeyeri deposited in the MOUFPE collection provides no further information about the habitat of this species.The scarcity of Brazilian records of C. hartmeyeri suggests that the species may be less common in the southwestern Atlantic, at least along the continental coast of Brazil.
The comparison between the material identified as C. hartmeyeri from Brazil and the type material of C. hartemeyeri from Jamaica, available in Manning [40], must be conducted with caution as both specimens are of different sexes.The holotype of C. hartmeyeri is a female, whereas the specimen from Brazil is a male (see [40]).Therefore, certain sexually dimorphic appendages such as chelipeds and first pairs of pleopods should not be considered in any taxonomic comparison between specimens of opposite sexes in this and other families of Axiidea.Taking the above into consideration, the shape of the anterior region of carapace, uropodal endopod and telson as described by Manning (fig.2a,b,h in [40]) for the reexamination of the holotype of C. hartmeyeri fit with the examined material of this species from Brazil (see also Figure 2A,E).Type locality.Martinique [42].
Remarks.As with C. hartmeyeri, C. longiventris appears to be uncommon along the Brazilian coast.Coelho [13] recorded C. longiventris from the northern region of Brazil (#1876).Unfortunately, this specimen is destroyed, making it impossible to confirm the identification made by Coelho [13].The other specimen deposited in the MOUFPE collec-tion (#1880), a female collected in the southeastern region of Brazil, is in good condition.The examination of this specimen raises some doubts about its correct identification as C. longiventris.In C. longiventris from Martinique, the posterior margin of the telson is rounded with a median prominence, whereas in the specimen from Brazil, it is straight and has a small median depression (see fig. 6d in [38]; see also Figure 3E).The remaining characters (e.g., spinous and articulated projections of carapace as well as ornamentation of chelipeds) seem to match the illustrations provided by Manning [38] for C. longiventris from Martinique.Further comparisons between Brazilian specimens assigned to C. hartmeyeri and C. longiventris and the type specimens of both species are necessary to ensure that these species are indeed present on the Brazilian coast.Type locality.Mouth of Rio Anil, São Luís, Maranhão, Brazil [44].
Remarks.Lepidophthalmus siriboia is endemic to Brazil (from Pará to Bahia), occurring primarily in estuarine areas of the northeastern region [12,44].This species is characterized by solitary habits [45].Morphologically, L. siriboia shares with L. louisianensis and L. statoni the presence of ventral abdominal not sclerotized ( [44], for the presence of ventral abdominal sclerotization, see [46]); however, this species can be distinguished from both L. louisianensis and L. statoni in having the terminal segments of the antennule and antenna with a parallel base (vs.non-parallel base of terminal segments of the antennule and antenna in L. louisianensis and L. statoni) (cf.fig.8a in [12] and fig.1a in [39]).
Genus Neocallichirus Sakai, 1988 [47] SUL II # 3, off São Paulo, 24.550 Remarks.Endemic to Brazil, this species has been recorded exclusively in the continental shelf of Rio de Janeiro [12].Two lots (MOUFPE: 15326, 15327), each containing one specimen, collected at two sites along the coast of São Paulo, extend the distribution of this species 800 km southward.

Discussion
Holdings of Axiidea deposited in the MOUFPE collection are summarized according to habitat in Table 1.This collection contains specimens of 23 out of the 35 Axiidea ghost shrimp species recorded on the Brazilian coast.Many more comparative studies between Axiidea material from the Brazilian coast and the respective types of each of these species are necessary to establish the taxonomic validity of Brazilian records, especially in the case of those species originally described in the northern hemisphere and reported for the Brazilian coast without any comparative work.From here, certainly, additional species of Axiidea have to be expected.(Coelho, 1973) [23] S Coelho 1997 [13] Meticonaxius capricorni Coelho, 1987 [66] S Coelho 1997 [13]

Table 1 .
Burrowing shrimp species of the infraorder Axiidea deposited in the Museu de Oceanografia Prof. Petrônio Alves Coelho, Universidade Federal de Pernambuco (MOUFPE).The habitat of each species, intertidal or subtidal, is represented by 'I' and 'S', respectively.The reference for a Brazilian record is provided here.