Parapaguridae, Smith, 1882

McLaughlin, P. A., 2003, Illustrated keys to families and genera of the superfamily Paguroidea (Crustacea: Decapoda: Anomura), with diagnoses of genera of Paguridae, Memoirs of Museum Victoria 60 (1), pp. 111-144 : 118

Key to genera of Parapaguridae

1. Corneas present.............................. 2

— Corneas absent ( Fig. 8l )........................................ Typhlopagurus de Saint Laurent, 1972

2. Rostrum short, not exceeding ocular peduncles...... 3

— Rostrum long, often exceeding ocular peduncles ( Fig. 1q ).......................... Probeebei Boone, 1926

3. Ocular acicles distinctly developed ( Figs 8a–c, e, l )... 4

— Ocular acicles weakly developed or obsolete ( Fig. 1p )........................ Tylaspis Henderson, 1885

4. Posterior carapace mostly membranous; unpaired left pleopods 3–5................................ 5

— Posterior carapace calcified; asymmetrically paired pleopods 3–5......... Bivalvopagurus Lemaitre, 1993

5. Shield about as broad or broader than long; rostrum bluntly triangular or broadly rounded; abdomen flexed. 6

— Shield distinctly longer than broad; rostrum acutely triangular; abdomen straight.......................................... Tsunogaipagurus Osawa, 1995

6. Shield distinctly broader than long; dactyls of ambulatory legs straight or nearly so; corneas strongly dilated ( Fig. 3m ); pleopod 2 of male with short exopod and strongly twisted distal segment ( Fig. 7e )....................................... Strobopagurus Lemaitre, 1989

— Shield about as broad as long; dactyls of ambulatory legs curved; corneas moderately or weakly dilated; pleopod 2 of male lacking exopod and distal segment not twisted ( Fig. 7f ) (rarely absent)........................ 7

7. Vestigial pleurobranch present on each side of somite XIV (thoracomere 8, above pereopod 5) ( Fig. 4e).................................. Sympagurus Smith, 1883

— Vestigial pleurobranch absent on each side of somite XIV (thoracomere 8, above pereopod 5)............... 8

8. Epistomial spine straight ( Fig. 8m ) or absent........ 9

— Epistomial spine strongly curved upward................................. Oncopagurus Lemaitre, 1996

9. Gill structure bi- or quadriserial ( Figs 4f–h); segment 4 of antennal peduncle armed with dorsodistal spine; length of ocular peduncles, including corneas, at least half length of shield....... Paragiopagurus Lemaitre, 1996

— Gill structure quadriserial ( Figs 4g, h); segment 4 of antennal peduncle unarmed; length of ocular peduncles, including corneas, less than half length of shield (except Parapagurus bouvieri Stebbing, 1910 )...................................... Parapagurus Smith, 1879

Figures

Figure 1. Morphological diversity among members of the Paguroidea. a, b, Coenobitidae, c, Pylochelidae; d–g, Diogenidae; h–k, Lithodidae, l–o, Paguridae, p, q, Parapaguridae: a, Birgus latro Leach; b, Coenobita clypeatus (Fabricius); c, Trizocheles spinosus (Henderson); d, Allodardanus bredini Haig and Provenzano; e, Dardanus venosus (H. Milne Edwards); f, Clibanarius arethusa De Man; g, Calcinus tibicen (Herbst); h, Cryptolithodes sitchensis Brandt; i, Hapalogaster dentata (De Haan); j, Sculptolithodes derjugini Makarov; k, Lithodes murrayi Henderson; l, Labidochirus splendescens (Owen); m, Propagurus gaudichaudi (H. Milne Edwards); n, Ostraconotus spatulipes A. Milne–Edwards; o, Porcellanopagurus edwardsi Filhol; p, Tylaspis anomala Henderson; q, Probeebei mirabilis Boone. [a, f after Alcock, 1905; b, from Chace and Hobbs, 1969; c, k, p, from Henderson, 1888; d, e, g, after Chace et al. 1985; h, from Makarov, 1938; i, j, from Vinogradov, 1950; l from McLaughlin, 1974; m, from Benedict, 1901 as Eupagurus patagonensis Benedict; n, after A. Milne-Edwards and Bouvier, 1893; o, after Forest, 1951; q, from Wolff, 1961; not to scale.]

Figure 3. Basic morphology: a, diagrammatic pagurid (whole animal, dorsal view); b, diagrammatic lithodid (whole animal, dorsal view). Cephalothorax or shield, with or without cephalic appendages: c–h Pylochelidae; i, Diogenidae; j, Pylojacquesidae; k–m Paguridae. c, Pylocheles; d, Trizocheles; e, Cheiroplatea; f, Pomatocheles; g, Parapylocheles; h, Cancellocheles; i, Diogenes; j, Pylojacquesia; k, Porcellanopagurus; l, Solitariopagurus; m, Hemipagurus. Abbreviations: aa = antennal acicle; ant. = antenna; antu = antennule; c, cornea; car = carpus; cg = cervical groove; dac = dactyl; ff = fixed finger; irp = intercalary rostral process; la = linea anomurica; lf ch = left cheliped; lf ur = left uropod; lp = lateral projection; lt = linea transversalis; mer = merus; oa = ocular acicle; op = ocular peduncle; P2–5 = pereopods 2–5; pcl = posterior carapace lobe; pcme = posterior carapace median element; pl3–5 = pleopods 3–5; plm = palm; pmp = posterior median plate; pop = postocular projection; pro = propodus; r = rostrum or rostral lobe; rt ch = right cheliped; s = shield; sl1–3 = shield lobes 1–3; t6 = abdominal tergite 6; tel = telson. [a, b, adapted from Sandberg and McLaughlin, 1998; c, d from Forest et al. 2000; e–h, from Forest, 1987; i, from McLaughlin and Clark, 1997; j, from McLaughlin and Lemaitre, 2001c; k, l, from McLaughlin, 2000; m, from McLaughlin, 1997 (as Catapagurus); not to scale.]

Figure 7. Secondary sexual appendages and structures: a, coxae of pereopods 5 and abdominal somites 1 and 2 of male with pleopods 1 and 2 paired, modified; b, c, coxae of pereopods 5 and abdominal somite 1 of female with pleopod 1 paired, modified; d, female brood pouch; e–g, male pleopod 2; h–q, male sexual tubes; r, male gonopores without sexual tube development; s, coxa of right pereopod 5 of male with gonopore masked by tuft of stiff setae; t, coxa of left pereopod 5 of male with gonopore masked by tuft of stiff setae. [a, from Forest et al. 2000; b, from McLaughlin and Haig, 1995; c, q, r, from McLaughlin and Lemaitre, 2001b; d, from McLaughlin and Provenzano, 1975; e, f, from Lemaitre, 1989; g, from Forest, 1995; i–n from McLaughlin, 1997; h, from Wang and McLaughlin, 2000; p, from McLaughlin, 1986; s, from Melin, 1939; t, from Forest, 1961; not to scale].

Figure 8. Additional morphological characters: a, c, shield with Y-shaped posterior groove; b, shield without Y-shaped posterior groove; d, last thoracic somite and abdomen of Xylopagurus (dorsal view); e, multifid ocular acicles; f, Lithodes rostral spine complex; g, dorsal and ventral rostral spines of Glyptolithodes; h, Cryptolithodes (ventral view) with carapace covering body and appendages; i, rostrum with epirostral spine (lateral view); j, symmetrical uropods and posterior portion of abdominal tergite 6, plus telson (dorsal view) k, right antennal peduncle with hooked spine (indicated by arrow) on lateral margin of segment 1; l, shield of Typhlopagurus showing spinose ocular and antennal acicles and lack of ocular peduncles; m, parapagurid epistome and labrum. Abbreviations: apr = anterior rostral process; ds = dorsal spine(s); es = epistomial spine; ls = labral spine; vs = ventral spine; 6 indicates abdominal tergite 6. [a, from McLaughlin and Hoover, 1996; b, from Forest and de Saint Laurent, 1968; c, from Forest and McLaughlin, 2000; d, from Lemaitre, 1995; e, McLaughlin and Murray, 1990; f, from Vinogradov, 1950; g, after Haig, 1974; h, from Makarov, 1938; i, from McLaughlin, 1997; j, from McLaughlin and Lemaitre, 1993; k, from McLaughlin, 1981; l, from de Saint Laurent, 1972; m, after Lemaitre, 1989; not to scale].