Pagurus criniticornis ( Dana, 1852 )

Nucci, Paulo Ricardo & Melo, Gustavo Augusto Schmidt De, 2007, Hermit crabs from Brazil. Family Paguridae (Crustacea: Decapoda: Paguroidea): Genus Pagurus, Zootaxa 1406, pp. 47-59 : 49-50

Pagurus criniticornis ( Dana, 1852)

(Figs. 1B, 2B, 3B, 4B)

Bernhardus criniticornis Dana, 1852: 448 ―1855: 9, pl.27, figs 8a–e.

Eupagurus criniticornis .— Stimpson, 1858: 237 ― Smith, 1869: 39 ― Moreira, 1901: 29, 88; 1906: 15.— Alcock, 1905: 181.— Baratini & Ureta, 1960: 54, pl.17.

Pagurus criniticornis .— Gordan, 1956: 329.— Forest & Saint Laurent, 1968: 124, figs 80, 83, 84, 88, 89.— Fausto- Filho, 1970a: 59; 1970b: 71.— Scelzo, 1971: 146.— 1976: 43.— Coelho & Ramos, 1972: 164.— Scelzo & Boschi, 1973: 207.— McLaughlin, 1974: 41; 1975: 372.— Boschi, 1979: 138.— Hebling & Brossi-Garcia, 1981: 765.— Lemaitre et al., 1982: 684, figs 1a, b.— Coelho & Ramos-Porto, 1986: 40.— Hebling & Rieger, 1986: 70.— Rieger, 1998: 414.— Melo, 1999: 124, fig. 68.

Diagnosis. Shield slightly longer than broad. Rostrum obtuse, slightly overreaching lateral projections. Ocular peduncles slender and shorter than shield width, with corneae slightly dilated. Ocular acicles with anterior margins rounded, with 1 strong submarginal spine; occasionally accessory marginal spinule on mesial margin. Antennular peduncles overreaching corneae; antennal peduncles usually not reaching distal margins of corneae; flagella long, usually overreaching right cheliped. Right cheliped with palm approximately twice longer than broad; dorsal face with 2 rows of spinose tubercles; carpus with rows of spines usually well developed on dorsomesial and dorsolateral margins. Left cheliped smaller than right, dorsal surface of carpi with 2 longitudinal rows of 4 or 5 spinose teeth; dorsal face of palm with 2 rows of spinose teeth. Surface of chelipeds covered by long setae which sometimes can hide the ornamentation. First pair of ambulatory legs with dactyls slightly longer than propodi; ventral margins each with row of corneous spines. Propodi unarmed. Telson with left lobe longer than right, both with 4 strong spines and intermediate spinules.

Distribution. Western Atlantic — Gulf of Mexico, Antilles, northern South America, Brazil (St. Peter and St. Paul Rocks and from Pernambuco to Rio Grande do Sul), Uruguay and Argentina.

Habitat. From intertidal to 60 metres, on sandy and muddy substrates.

Material examined. Brazil: St. Peter and St. Paul Rocks, 4 males: 2.5, 1.2, 1.1, 1.6 mm, 2 females: 1.9, 2.0 mm ( MZUSP –9609). Espírito Santo – Vitória, Ilha Galheta, 1 male: 2.8 mm ( MZUSP –12911). Rio de Janeiro — Proj. Ilha Grande, st. 45, 1 male: 1.5 mm ( MZUSP –13376); st. 304, 1 female: 1.6 mm ( MZUSP – 13872); st. 212-F, 1 male: 2.0 mm ( MZUSP –13362); st. 235, 1 male: 1.8 mm ( MZUSP –13377); Manguinhos, 3 females: 2.2, 1.5, 1.4 mm, 1 male: 2.1 mm ( MZUSP –4712). São Paulo – Ilha de São Sebastião, Praia Garapocaia, 4 males: 2.5, 2.4, 2.2, 1.8 mm, 1 female: 2.8 mm ( MZUSP –13352); Praia do Veloso, 9 females: 2.8, 2.7, 2.8, 3.0, 2.0, 2.5, 2.2, 2.0, 1.7 mm, 4 males: 3.6, 1.7, 2.1, 1.4 mm ( MZUSP –13358); São Sebastião, Praia Araçá, 7 males: 3.2, 2.7, 2.8, 2.4, 2.7, 2.5, 2.6 mm, 1 female: 2.5 mm ( MZUSP –12990); Saco Grande, 1 male: 2.4 mm ( MZUSP –12993); Guarujá, Praia Branca, 1 male: 2.5 mm ( MZUSP –13357); Santos, 1 male: 1.8 mm ( MZUSP –13356); Proj. REVIZEE, st. 6658 (near the border of Paraná), 1 male: 1.4 mm ( MZUSP – 13909).

Remarks. According to Forest & Saint Laurent (1968), Pagurus criniticornis shows remarkable individual variations, which can cause doubts in identification. Perhaps one of the most important variations is in the length of the antennal peduncles. Forest & Saint Laurent (1968) observed that specimens from high latitudes ( Uruguay and Argentina) had the antennal peduncles distinctly longer than the corneae, whereas in specimens from northern regions, the antennal peduncles reached only the anterior margins of the corneae. We examined specimens from Ilha Grande, Rio de Janeiro, in which the antennal peduncles overreached the corneae. Thus if there exist two populations of Pagurus criniticornis , one with antennal peduncles overreaching the corneae (in the south) and another with antennal peduncles shorter than the corneae (in the north), the distributional limits of these populations are unclear.