taxonID	type	description	language	source
664D87EBFF9C5056FC9F76519537FBA6.taxon	materials_examined	Material examined Holotype: female (9.0 mm) and allotype male (3.1 mm) (MZUSP 18,339). Type locality Off Isla La Vieja, Bahía Independencia, Reserva Nacional de Paracas, Pisco, Peru (14 ° 15´48.36 ″ S, 76 ° 11´46.4 ″ W). Description of holotype Female outline ovoid, body margins slightly distorted dextrally (≈ 10 °) (Figure 1 A – B); total length 9.0 mm, maximal width at third pereomere; antennae, antennules and pereopods visible in dorsal view; head distinct from first pereomere, broader than long, surface smooth, front with broad lamina, eyes and pigmentation absent; anterolateral corners of head sharply angled. Maxilliped distally tapering, palp lacking, spur long and narrow (Figure 2 C). Antennule 3 – segmented (Figure 2 A); basal segment subquadrate, lacking setae; second segment subcylindrical with subapical setae; third segment ovate, smaller, tuft of short setae on tip. Antenna 5 – segmented (Figure 2 B); basal segment quadrate, lacking setae; segments 2 – 4 subcylindrical, distal segments progressively narrower, segment 2 distalmost with ring of distal setae, terminal segment minute, tuft of small setae at tip (Figure 2 A); barbula formed by pair of acute, distally recurved lateral smooth projections; central region with undulating margin (Figure 2 D). Pereomeres dorsally, ventrally and laterally distinct; pereonites 1 – 4 with well-developed coxal plates and large dorsolateral bosses; pereonites 5 – 7 with weakly-developed coxal plates and lacking bosses (Figure 1 A). Oostegites fully enclosing brood pouch (Figure 1 B); first oostegite 2 – segmented (Figure 2 E), covering head and forming anterior part of brood pouch, external surface smooth; anterior segment subtriangular, slightly more than 1.5 - times as long as tapered posterior segment, which is approximately as wide as high, with posteriorly-directed thin digitate lobe; inner surface concave in both segments; oostegites 2 – 5 large and ovate, increasing in size posteriorly; fifth oostegite with posterior marginal fringe of setae (Figure 2 I), extending across posterior border of marsupium and overlapping opposite oostegite. Pereopods similar but progressively smaller posteriorly (Figures 2 F – H), bases wide and rectangular, ischia cylindrical with slightly crenulated ventral edge, meri subquadrate, carpi conical, propodi swollen distoventrally with deep socket present; dactyli strongly recurved. Pleon approximately 30 % as long as head / pereon (Figure 1 A); five pleomeres dorsally and laterally separated, pleotelson bilobed; pleomeres laterally rounded without lateral plates; five pairs of biramous elongate, swollen pleopods, endopods and exopods both well developed (Figure 1 A – B); margins of pleopods smooth with surfaces sparsely covered in large swollen tubercles (Figure 2 J), uropods uniramous, similar in shape but smaller than pleopods, with swollen tubercles (Figure 2 K). Male (Figure 3 A – B). Body generally unpigmented with few small spots on anterolateral margins of pereomeres, body elongated, all segments clearly segmented dorsally, ventrally and laterally; head suboval, distinct from first pereomere; approximately 1.7 - times as wide as long; anterolateral borders rounded, head approximately 70 % as wide as first pereomere; eyes present mediolaterally; antennule of three articles, antenna of seven articles, both distally setose (Figure 3 C – D). Pereomeres not widely separated, maximal width at third and fourth pereomeres, tapering anteriorly and posteriorly; midventral tubercles absent; generally isomorphic pereopods but progressively smaller dactyli and propodi and larger ischia posteriorly (Figure 3 B, E – G). Pleon with five segments plus pleotelson. Pleomeres progressively narrower posteriorly, distinctly separated, tips rounded; globose uniramous pleopods on pleomeres 1 – 5 near midline (Figure 3 B, H – I); pleotelson produced in two tapered lateral lobes and prominent medial anal cone, small tuft of setae on distolateral tips of projections; uropods absent (Figure 3 J). Etymology This specific name refers to the lack of dramatic asymmetry in females of this species that is, except in A. foresti, otherwise characteristic of the species in the genus. Remarks Markham (2003) listed seven genera of branchial parasitic bopyrids from hermit crab species (Diogenidae, Paguridae and Parapaguridae), but currently there are eight including Bopyrophryxus Codreanu, 1965 (Bourdon and Boyko 2005). In only one of these eight genera are the propodi of the female’s pereopods modified into “ sockets ” for insertion of the dactyli, and so we must assign this new species to Asymmetrione. The near total lack of asymmetry of the female reported here does not in itself preclude inclusion of the species in Asymmetrione. In fact, the genus Megachelione Bourdon, 1968, with sole species M. foresti Bourdon, 1968, was synonymized with Asymmetrione by Markham (1975) after determination that the only character separating these two genera was the degree of asymmetry of the females. In all respects, including the limited asymmetry, the new species described here resembles A. foresti. It can be separated from A. foresti by the shape of the female head (ovate in A. foresti vs. distinctly wider than long in A. aequalis), development of the female pereon coxal plates (well developed on pereomeres 1 – 4 with incomplete plates on 5 and 6 in A. foresti vs. pereomeres 1 – 4 only in A. aequalis), and female pleomere lateral plates (well developed on pleomeres 1 – 5 in A. foresti vs. lacking in A. aequalis), as well as the size of the anal cone in males (subequal to pleotelson posterolateral projections in A. foresti vs. much shorter than pleotelson posterolateral projections in A. aequalis). Although Markham (1975) stated that A. desultor Markham, 1975, was similar to A. foresti, the present species is much more so. A key is given below to facilitate the separation of the females of the 10 species of Asymmetrione now known. In many cases, the males are either not described in enough detail or lack obvious characters to separate them easily, although some species (e. g., A. clibanarii) are quite distinct from others. Although the males can be difficult to separate, their uniformity in almost all characters (except for the number of antennal segments and pleotelson / uropod or posterolateral projection ratios) supports the inclusion of all 10 species in Asymmetrione, as does the shared character of the propodal “ socket ” in females.	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF9C5056FC9F76519537FBA6.taxon	discussion	Remarks on the Bopyridae of the southeastern Pacific	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF905057FC93733195B6FF6E.taxon	materials_examined	Material examined Sinistral female and attached male from 23.8 mm carapace length female Galacantha diomedeae, from off Arica, Chile (18 ° 28´30 ″ S, 70 ° 18´52 ″ W), 400 m depth (USNM 1125508). Remarks	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF915057FCCF730997FCFA9E.taxon	discussion	Remarks This species has only been reported once as a parasite of Petrolisthes armatus (Gibbes, 1850) from Matapalo (near Capon), Peru. It is the only bopyrid known from porcellanid crabs in the region.	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF915050FC67723995D6FE8E.taxon	discussion	Remarks	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF915057FCDA7419977AFBAE.taxon	discussion	Remarks This species has only been recorded as a single pair from the type locality of Port Otway in Chilean Patagonia, infesting the branchial chamber of Munida curvipes (Richardson 1904).	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF915057FCC176499253FCBE.taxon	discussion	Remarks This species was originally described by Richardson (1904) from a single mature pair collected off Port Otway, Chilean Patagonia. Miranda-Vargas and Roccatagliata (2004) subsequently published a detailed redescription of both sexes based on several specimens collected from two different hosts from Argentinean Patagonia. Pseudione tuberculata parasitizes three lithodid hosts (see Table 1) from Patagonian austral waters. The prevalence of P. tuberculata in Paralomis granulosa can reach nearly 46 % in hosts of carapace length of 10 – 19.9 mm, but this rate steeply declines as host size increases (Roccatagliata and Lovrich 1999). Cañete et al. (2008) reported high prevalence (near 30 %) of P. tuberculata from juveniles of Lithodes satolla in the Magellan region. Detrimental effects reported for P. granulosa include sterilization and reduction of growth (Roccatagliata and Lovrich 1999). High mortality is also suspected in small-sized crabs and evidence of former parasitization in larger hosts has been found (Roccatagliata and Lovrich 1999).	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF965050FC2675B995C3FBCE.taxon	discussion	Remarks	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF965051FF4A738995B7FF4E.taxon	materials_examined	Material examined Sinistral female and attached male from 20.9 mm shield length male N. uncinata, San Carlos, Valdivia, Chile (39 ° 51´42 ″ S, 73 ° 26´25 ″ W), 5 m depth (USNM 1125509). Remarks	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF965050FC1976299287FD1E.taxon	discussion	Remarks	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF975052FCC5739C9565FDAE.taxon	discussion	Remarks A single pair with a juvenile female were found attached to the dorsal abdominal region of Pagurus villosus hosts during a year-round survey of hermit crabs in Central Chile (Pardo et al. 2007), but were unfortunately lost in a fire at one of our collection labs (LMP); photographs of the specimens are still extant but are too poor for publication. The characters of the juvenile female specimen, particularly the pleotelson shape, appear similar to those seen on the female holotype of A. thompsoni (see earlier), while the pleotelson of the mature female resembles that of A. hyptius adult females. Previous records of A. hyptius cover a wide range of the North and South American Atlantic coasts, parasitizing several species of Pagurus and Iridopagurus (Boyko and Williams 2003) from Massachusetts, USA to Curaçao, and a similar, perhaps identical, species was collected in the Beagle Channel (Argentina) as the south- ernmost locality recorded for any member of the genus (Diaz and Roccatagliata 2006). If the present material proves to be identical with the true A. hyptius, this would constitute the first record in Pacific waters, as well as a new host record. If the Chilean material is distinct from A. hyptius, it may represent A. thompsoni (see earlier) that was described from a possibly juvenile female and adult male, and would provide the first host identification for this species. It is also possible that the Chilean and Argentinean Anathelges material are conspecific but distinct from the northern Atlantic specimens of A. hyptius. As the Chilean specimens are lost, more collection must be done along with detailed comparison of northern Atlantic material, Argentinean, and Chilean specimens. Prevalence of A. cf. hyptius in P. villosus was much lower 0.07 % (n = 2751) than even the low numbers recorded from Pagurus comptus White, 1847, from Patagonian waters (0.5 %, n = 3143) (Diaz and Roccatagliata 2006).	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF975051FC4274739582FB34.taxon	discussion	Remarks This species is very similar to A. hyptius and the characters of the female, especially the pleotelson, may be juvenile in nature in the only known specimen (but see Markham (1974) and Boyko and Williams (2003 )). The species may be synonymous with A. hyptius (see later) but is in need of redescription based on additional material. Anathelges thompsoni has only been recorded as a single heterosexual pair from the type locality of Valparaiso in central Chile infesting an unidentified pagurid host (Nierstrasz and Brender à Brandis 1931; Boyko and Williams 2003).	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
664D87EBFF975051FCA276699566FD7E.taxon	discussion	Remarks	en	Pardo, Luis Miguel, Boyko, Christopher B., Mantelatto, Fernando L. (2009): Description of a new species of Asymmetrione (Isopoda: Bopyridae: Pseudioninae) infesting the hermit crab Paguristes tomentosus (Anomura: Diogenidae) from Peru, with a key to species and a review of southeastern Pacific bopyrids. Journal of Natural History 43 (33 - 34): 2041-2055, DOI: 10.1080/00222930903094639, URL: http://dx.doi.org/10.1080/00222930903094639
