Decapoda - Anomura - Paguridae - Anisopagurus

Anisopagurus pygmaeus (Bouvier, 1918)

World Distribution
Felder et al. (2009) - Fla Keys, Cuba–Curaç. Deep distribution from Karubenthos 2012, 15-16 m.

Environnement : Marine - Substrat/Association : Hard bottom (rock and rubbles)

Vertical range : Shallow-waters (0-100 m) - Min-Max observed: 15-16 m

Lesser Antilles data
Distribution: ICA (?St Martin, St Barthélemy, Guadeloupe), IOV (Curaçao). 15-16 m. WA.
Pagurus pygmaeus - Hazlett, 1966: 72, Curaçao. - Rodríguez, 1980: 233 (Curaçao, from Hazlett).
Anisopagurus pygmaeus - Lemaitre & McLaughlin, 1996: 104, tab. 2, Curaçao. - Questel, 2019: 10, St Barthélemy.
Anisopagurus pygameus - Saint Martin, RNN Inventory 2012, 21/04/2012, UF32395, photo Dstm_6837; UF32394, photo Dstm_6840; UF32397, photo Dstm_6844.
Anisopagurus pygmaeus - Guadeloupe - Karubenthos 2012, det. R. Lemaitre, mail 19 August 2015, Anisopagurus pygmaeus, 1 male 0.9 mm, 1 ovig. Female 1.3 mm [with 5 large eggs], st. GB23, 16°30.04’N, 61°28.79’W, 16 m, 19 May 2012, MNHN-IU-2013-5317; 3 males 0.7–1.0 mm, Petite Terre, Guadeloupe, Lesser Antilles, Caribbean Sea, st. GB31, 16°09.71’N, 61°07.73’W, 15 m, 26 May 2012, MNHN-IU-2013-5472 [larger male photographed by D.L. Felder]
Comment: According to R. Lemaitre, that has examined the color photographs from St Martin, this species can be easily confused with Clibanarius tricolor with similar coloration and also occuring in the shallow water habitat.

Comment(s) on data
Pre-det by R. Lemaitre, August 2014 with this comment - This is a Paguridae, for certain, and although it is difficult to even guess with the views you sent, the armature and shape of the chelipeds, and general morphology of the ambulatory legs, do have some resemblance to Anisopagurus pygmaeus (Bouvier, 1918).
Comment Paulay, August 2014 - The animal is common, but very restricted in habitat. We got it only at a partly-exposed boulder beach at 1-2m depth. Very particular to that zone.
Mail Lemaitre August 2015 : Darryl reminded me that Hazlett (1966), in his behavioral study from Curacao, indicated quite well the habitat of Anisopagurus pygmaeus: “ well-circulated shallow subtidal waters where they were typically concealed beneath stones on rocky hard substrates covered by encrusting red algae...” It is amazing because this tiny hermit could easily be confused, if one is not careful or thinking... with Clibanarius tricolor, given the often boring abundance in that same shallow habitat where these 2 species co-occur.

Note that after Besse 2013, these specimens (at least 5317, 5472, probably also 5473) were pre-det by R. Lemaitre as Genus? Operculate chela - Guadeloupe - Karubenthos 2012, pre-det. R. Lemaitre, Besse 2013, 2 spp., st. GB23, 16 m, lot JL1120, MNHN IU-2013-5317; 4 spp., st. GB31, 15 m, lot JL1430, MNHN IU-2013-5472, 1 sp., MNHN IU-2013-5473. with this remark: Probably new species; 2 specs: 1 ovig female, 1 left in shell. Right chela is distinctive, pinkish, margins well delimited by strong spines.

References : PDF list, 214 pp (1.4 Mo)

This species in Worms Database