Sympagurus papposus, Lemaitre, 1996

Lemaitre, R., 1996, Hermit crabs of the family Parapaguridae (Crustacea: Decapoda: Anomura) from Australia: species of Strobopagurus Lemaitre, 1989, Sympagurus Smith, 1883 and two new genera., Records of the Australian Museum 48 (2), pp. 163-221 : 180-184

Sympagurus papposus n.sp.

Figs 3c,d, 5b, 8-10

Sympagurus dofleini .- Lemaitre, 1994: 387 (in part) (Not Sympagurus dofleini [ Balss, 1912]). (See remarks).

Holotype. Female ovig. (SL 14.3 mm), E of Broken Bay, FRV Kapala , sta. K75-0l-02, 33°38-34'S, 151°57'­ l52°0l'E, 786 -804 m, 2 Apr 1975, AM P44482.

Paratypes from Australia. WESTERN AUSTRALIA: 1 male (SL 7.8 mm), W of Cape Leveque , FRV Soela , sta. SOI/841092, 16°09.5'S, 120008.8'E, 600- 596 m, 18 Feb 1984, WAM 1241 86. 1 male (SL 12.1 mm), Scampi Trawl Grounds, Comoe Endeavour , sta. WH 85-15, 17°22'S, 118°38'E, 430 m, 2 Nov 1985, NTM Cr 006863. 1 male (SL 12.0 mm), North West Shelf , FRV Soela, sta. NWS-7, Scampi Shot 2, 18°32.2'S, 117°30.9'E, 392- 400 m, 25 Jan 1983, coil. A.I Bruce, NTM Cr 010911. I male (SL 13.0 mm), North West Shelf , FRV Soela , CSIRO , cruise 0184, sta. NWS-36 TIlO, 19°15'S, 115°38'E, 404 m, 29 Jan 1984, coil. A.I Bruce, USNM 270108 . 2 females ovig. (SL 9.5, 10.8 mm), North West Shelf , FRV Soela , CSIRO , cruise 0184, sta. T8 , 19°20.2'S, 115°44.1'E, 306-308 m, 29 Jan 1984, NTM Cr 000663, 000664. 3 males (SL 11.0 - 14.5 mm), West Shelf , FRV Soela , sta. SOI-84-61, 11 Feb 1984, coil. T . Ward , AM P39452 .

QUEENSLAND: 1 male (SL 14.2 mm), Marion Plateau, FRV Soela , sta. 0685-08, 22°55.1'S, 154°21.25'E, 590-606 m, 17 Nov 1985, NTM Cr 006852. 1 male (SL 14.0 mm), Craigmin Survey, sta. 26, 23°15.3'S, 154°21.7'E, 549 m, 4 Oct 1980, QM W10129 . 1 female (SL 13.9 mm), FRV Craig Mor , shot 14, 23°18'S, 154°13'E, 530 -585 m, 4 Oct 1980, NTM Cr 001157. 1 female ovig. (SL 11.0 mm), MV Iron Summer, shot 2, 27°19'91"S, 153°53'47"E, 600 m, 10 May 1983, trawled, QM W14338 . 1 female ovig. (SL 13.3 mm), off N Stradbroke Is., MV Iron Summer, 27°35.5'S, 153°56.7'E, 520 m, 31 Mar 1983, trawled, coil. R . Noreton , QM W16520 . 1 female ovig. (SL 14.0 mm), off N Stradbroke Is., MV Iron Summer, 27°36.5'S, 153°57'E, 550 m, 23 Nov 1982, trawled, G. Smith , QM W6518 . 1 male (SL 16.6 mm), off N Stradbroke Is., MV Iron Summer, 27°40'S, 153°56.9'E, 530 m, 22 Nov 1982, trawled, G. Smith, USNM 270109 . 1 male (SL 15.0 mm), off Southport, MV Iron Summer, 27°59.4'S, 154°00.1'E, 590 m, 31 Mar 1983, trawled, coil. R . Noreton , QM W16519 .

NEW SOUTH WALES: I female (SL 8.0 mm), 30031 '-19'4"S, 161°54'2"-40'6"E, RV Dmitry Mendeleev , cruise 16, sta. 1245, 29 Dec 1975, NMV J11164 . 1 female (SL 11.7 mm), E of Broken Bay , 33°30 -27'S, 152°05-07'E, FRV Kapala, sta. K76- 24-04, 819-823 m, 21 Dec 1976, AM . 3 males (SL 11.1- 16.4 mm), 6 females ovig. (SL 11.8-14.5 mm), off Broken Bay , FRV Kapala, sta. K75-05-05, 33°32-38'S, 152°00-04'E, 823 m, 19 Aug 1975, AM P21008. 1 male (SL 16.3 mm), E of Broken Bay , FRV Kapala, sta. K77-23-12, 33°35 -33'S, J52°00 -02'E, 823 m, 8 Aug 1977, AM P26794. 3 males (SL 14.6-17.1 mm), E of Broken Bay , FRV Kapala, sta. K75- 01-02, 33°38-34'S, 151°57'- 152°01'E, 786-804 m, 2 Apr 1975, AM P20495. 1 male (SL 17.0 mm), S of Sydney , FRV Kapala, sta. K07-01, 34°00'S, 151°43'E, 732 m, 6 Nov 1972, USNM 270110. 1 male (SL 10.4 mm), 40 km ESE of Ulladulla , FRV Soela, sta. S03/88/20, 35°31.29'S, 150049.85'E, 910 m, Engels high-lift demersal, colI. M. Norman, NMV J16189 . 1 male (SL 7.9 mm), E of Eden , FRV Kapala, sta. K83- 12-02, 37°36'S, 150021'E, 860-960 m, 26 Sep 1983, AM P44031 .

Other Paratypes. INDONESIA: 1 female ovig. (SL 9.7 mm), Indonesia, Java Sea , Siboga Exp., sta. 314, 07°36'S, 117°30.8'E, 694 m, 17 Jan 1900, ZMK .

WESTERN INDIAN OCEAN: 1 male (SL 11.0 mm), 1 female (SL 12.8 mm), Madagascar, Vitiaz , cruise 17, leg 3, sta. 2635, 25°05'S, 35°15'E, 228- 205 m, 25 Nov 1989, LACM 95 - 17.1 . 2 females ovig. (SL 11.2, 12.9 mm), Tulear [SW Madagascar], Vitiaz, cruise 17, sta. 2707, 33°01.8'S, 44°23.6'E, 910- 925 rn, 15 Dec 1988, USNM 270111 .

Description. First 11 pairs of gills intermediate, weakly divided distally ( Fig. 9f ), or occasionally phyllobranchiate (Fig. ge). Shield (Fig. 8a) as broad as long; dorsal surface frequently weakly calcified medially, with scattered short setae; rostrum broadly triangular, with short middorsal ridge; anterior margins sinuose; lateral projections broadly rounded, often nearly obsolete; anterolateral margins slightly sloping; posterior margin broadly rounded. Anterodistal margin ofbranchiostegite rounded, unarmed, setose.

Ocular peduncles about half length of shield, with row of long setae dorsally. Cornea slightly dilated. Ocular acicles subtriangular, terminating in strong spine (occasionally bifid or trifid); separated basally by less than basal width of 1 acicle.

Antennular peduncle long, slender, exceeding distal margin of corneae by halflength of penultimate segment. Ultimate segment twice or more as long as penultimate segment, naked or with scattered setae. Basal segment with strong ventromesial spine; lateral face with distal subrectangular lobe armed with 2 to 5 small spines, and strong spine proximally. Ventral flagellum with about 9 articles.

Antennal peduncle ( Fig. 9d ) exceeding distal margin of cornea by approximately half length of 5th segment. Fifth segment with scattered setae on lateral margin, and row of long setae dorsodistally. Fourth segment unarmed. Third segment with strong ventromesial distal spine. Second segment with dorsolateral distal angle produced, terminating in strong, multifid spine; mesial margin with spine on dorsodistal angle. First segment with small tubercle on lateral face; ventromesial angle produced, with 3 to 7 small spines laterally. Antennal acicles nearly straight (in dorsal view), exceeding distal margin of corneae by about 0.25 length of acicle, terminating in strong spine; mesial margin armed with 7 to 13 wellspaced spines, setose. Flagellum long, naked or with inconspicuous short setae less than half 1 flagellar article in length, exceeding extended right cheliped and ambulatory legs.

Mandible with 3-segmented palp. Maxillule ( Fig. 9a,b ) with external lobe of endopod weakly developed, internal lobe with 2 or 5 long setae. Maxilla with endopod slightly exceeding distal margin of scaphognathite. First maxilliped with endopod slightly exceeding exopod in distal extension. Second maxilliped without distinguishing characters. Third maxilliped ( Fig. 9c ) slender, distal 3 segments each 3 times as long as broad; crista dentata formed of 14 to 17 corneous-tipped teeth; coxa and basis each with small mesial tooth. Sternite of 3rd maxillipeds with small spine on each side of midline. Epistome with short, straight spine (often blunt), or unarmed. Labral spine present.

Chelipeds markedly dissimilar. Right cheliped (Fig. 8f) massive, with dense plumose setae. Fingers straight, terminating in small corneous claw; cutting edges each with irregularly-sized calcareous teeth; dorsal and ventral faces each with row of tufts of setae parallel to cutting edge. Dactyl subequal in length to palm, set at weakly oblique angle to longitudinal axis of palm; mesial face rounded, with irregular rows of small spines; dorsal and ventral faces unarmed or at most with scattered small tubercles. Fixed finger with dorsal and ventral surfaces similar to dactyl. Palm about as long as broad; lateral and mesial faces rounded, with irregular rows of wellspaced small spines; dorsal and ventral surfaces smooth or at most with scattered tubercles. Carpus with small, well-spaced tubercles or spines on dorsal surface, dorsodistal margin unarmed; ventral surface with scattered small tubercles. Merus with dorsal surface similar to that of carpus; ventromesial margin with row of small spines. Coxa and ischium with small spines on ventral face· coxa with ventromesial row of setae.

Left cheliped (Fig. 8e,d) well calcified, with dense plumose setae. Fingers terminating in small corneous claws; dorsal and ventral surfaces smooth except for tufts of setae; cutting edge of dactyl with row of minute, fused corneous teeth; cutting edge of fixed finger with row of regularly-spaced, small calcareous teeth interspersed with minute, fused corneous teeth. Dactyl about 1.3 times as long as palm. Palm unarmed or occasionally with dorsomesial row of small tubercles or spines; ventral surface smooth or with scattered small tubercles. Carpus with dorsal surface usually unarmed (Fig. 8d), or occasionally with row of small tubercles or spines on dorsal margin (Fig. 8e); ventral surface smooth. Merus with dorsal surface unarmed or at most with small, low tubercles on dorsal margin; ventral face often with scattered small spines. Ischium with row of spines on ventral margin. Coxa unarmed but with ventromesial row of setae.

Ambulatory legs (Fig. 8g-i) similar from right to left, long, reaching to extended right cheliped; ischium, merus, carpus and propodus with scattered short setae. ~actyl about 1.4 times as long as propodus, terminating m sharp corneous claw; with dorsomesial row of long setae, and ventromesial row of about 17 to 30 small corneous spines. Carpus with small dorsodistal spine (often blunt). Merus of 2nd pereopods usually with row of small spines on ventral margin. Ischium and coxa unarmed. Anterior lobe of sternite of 3rd pereopods (Fig. 8j) with strong marginal spine (sometimes bifid), setose.

Fourth pereopod (Fig. 8k) semichelate. Dactyl subtriangular, terminating in sharp corneous claw, and ventrolateral row of small corneous spinules. Propodus with. d~rsal margin longer than dorsoventral height, rasp conslstmg of 2 or 3 rows of conical scales. Carpus with long setae on dorsal margin. Merus with rows of long setae on dorsal and ventral margins.

Fifth pereopod (Fig. 81) semichelate. Propodal rasp extending to mid-length of segment.

Uropods and telson ( Fig. 9i,j , 10) markedly asymmetrical. Telson with transverse suture; dorsal surface with scattered short setae; female with ventrolateral margin of left anterior lobe (occasionally also of right lobe) with cluster of corneous spines mixed with long bristle-like setae ( Fig. 1 Oc-e); male with ventrolateral margins of anterior lobes with long setae ( Fig. 1 Oa,b); both sexes with posterior lobes separated by U- or V-shaped cleft, terminal margin of lobes armed with corneous spines.

Males with paired 1st and 2nd gonopods well developed. First gonopods ( Fig. 9g ) each with ovate, weakly concave distallobe. Second gonopods ( Fig. 9h ) each occasionally with rudimentary exopod on one side; distal segment nearly flat, setose on distomesial face, with row of short setae on lateral margin; basal segment with long setae on posterior face. Females rarely with rudimentary paired 1st pleopods, and vestigial 2nd right pleopod.

Habitat and symbiotic associations. Found living III zoanthids (probably Epizoanthus sp.; Fig. 5b).

Distribution. Indo Pacific: Madagascar; Indonesia; and Australia. Depth: 205 to 960 m.

Etymology. The specific name is derived from the Latin pappus, bristles, and refers to the characteristic spines and bristle-like setae on the telson in females of this species.

Affinities. This new species closely resembles Sympagurus dofleini ( Balss, 1912) (see Lemaitre, 1994: 384, figs 7, 8). Female specimens of S. papposus can immediately be separated from male or females of S. dofleini by the ventrolateral armature of the anterior lobes of the telson. Females of the new species have the left anterior lobe (and sometimes also the right anterior lobe) armed ventrolaterally with a fringe or cluster of corneous spines mixed with long bristle-like setae (Fig. lOc-e). In S. dofleini the anterior lobes in both sexes have at most a row of long setae ventrolaterally. In contrast to females, males of the two species can be separated using only a number of subtle but distinct differences. The anterolateral projections ofthe shield are broadly rounded, often obsolete (Fig. 8a), on S. papposus , whereas they are broadly triangular and often terminate acutely on S. dofleini . The armature of the antennal acicles in the two species differs in that the spines are stronger and more broadly spaced on S. papposus ( Fig. 9c ) than S. dofleini ( Fig. 11a ). The gills of S. papposus are phyllobranchs, or intermediate branchiae with lamellae weakly divided distally (Fig. ge,f); the gills of S. dofleini are intermediate with lamellae deeply divided distally ( Fig. 11b ). The distal lobe of the male 1st gonopod ( Fig. 9g ) is broader in S. papposus than S. dofleini .

Although there is some interspecific overlap in the range of variation of the armature of the carpus of the left cheliped in S. papposus and S. dofleini , this character can also be of help in differentiating the two species. The carpus of the left cheliped of S. papposus is usually unarmed dorsally (Fig. 8d), whereas the carpus of S. dofleini has a row of spines or tubercles on the dorsal margin (in addition to one or more dorsodistal spines).

The two species also differ in their habitat and symbiotic associations. Sympagurus papposus has been found living exclusively in large zoanthids ( Epizoanthus sp.; Fig. 5b), whereas S. dofleini is commonly found living in large actinians of the genus Stylobates which secrete a chitinous pseudo-shell (see Fautin Dunn et al., 1980; Fautin, 1987).

Remarks. During a study of parapagurids from French Polynesia, Lemaitre (1994: 387) mentioned under the distribution of S. dofleini that he had examined specimens of that species from Australia. However, reexamination of those specimens showed that they actually represent the new species S. papposus . Sympagurus dofleini has not been found to date in Australian waters.

Figures

Fig. 9. Sympagurus papposus n.sp. a, left maxillule, internal, b, endopod of same; c, left 3rd maxilliped, internal; d, right antennal peduncle, lateral; e,f, branchia, transverse section; g, male left 1st gonopod, mesial; h, male left 2nd gonopod, anterior; i,j, exopod of uropods, dorsal: i, left, j, right. Scales = 2 mm (a,d,i,j), I mm (b,e, g,h), 4 mm (c), and 0.5 mm (f). (a-d,f-j, paratype male [SL 12.1 mm], Western Australia, NTM er 006863; e, paratype male [SL 14.0 mm], Queensland, QM WIOI29).

Fig. 1. Strobopagurus sibogae (De Saint Laurent, 1972). a, shield and cephalic appendages; b, left cheliped; c, right cheliped; d, right 2nd pereopod, lateral; e, merus of same, lateral; f, right 3rd pereopod, lateral; g, merus of same, lateral; h, propodus and dactyl of left 4th pereopod, lateral; i, telson. Scales = 2 mm (a-c), 3 mm (d-g), 0.5 mm (h), and 1 mm (i). (Male [SL 6.0 mm], Western Australia, WAM 1314 -86).

Fig. 11. Sympagurus dojleini (Balss, 1912). a, antennal acicles, dorsal; b, branchia, transverse section. Scales = 1 mm (a), and 0.5 mm (b). (Hawaiian Is.: a, male [SL 17.5 mm], USNM; b, female [SL 18.8 mm], BPBM).