Areopaguristes lemaitrei, Ayón-Parente, Manuel & Hendrickx, Michel E., 2012

Ayón-Parente, Manuel & Hendrickx, Michel E., 2012, Two new species of hermit crabs of the genus Areopaguristes Rahayu & McLaughlin, 2010 (Crustacea: Anomura: Paguroidea: Diogenidae) from the eastern tropical Pacific, Zootaxa 3407, pp. 22-36 : 23-29

publication ID	https://doi.org/ 10.5281/zenodo.211808
DOI	https://doi.org/10.5281/zenodo.6179726
persistent identifier	https://treatment.plazi.org/id/5F1F87F1-FFA6-3130-FF61-FC3DFCA92FBA
treatment provided by	Plazi
scientific name	Areopaguristes lemaitrei
status	sp. nov.

Treatment

Areopaguristes lemaitrei View in CoL sp. nov.

( Figs 1–3 View FIGURE 1 View FIGURE 2 View FIGURE 3 )

Paguristes View in CoL sp.— Westervelt, 1967: 64, 75.

Areopaguristes View in CoL sp 1.— Ayón-Parente & Hendrickx, 2010: 4.

Material examined. Holotype: male (SL 3.40 mm), Estero de Urias, Mazatlán, Sinaloa, Mexico (23°11’00’’N, 106°21’42’’W), 15 Mar 2006, Van Veen dredge, 1 m (EMU-9520). Paratypes: 1 male (SL 1.89 mm), 1 female (SL 1.87 mm), and 1 ovig. female (SL, 3.05 mm), Estero de Urias, Mazatlán, Sinaloa (23°11’00’’N, 106°21’42’’W), 19 May 2006, Van Veen dredge, mud, 1 m (EMU-9521); 1 male (SL 2.90 mm), Punta Central, Bahía Kino, Sonora (28°45’43’’N, 111°56’25’’W), 9 Mar 2007 (EMU-9252); 1 male (SL 3.97 mm), Bahía Kino, Sonora (28°45’43’’N, 111°56’28’’W), 9 Mar 2007 (EMU-9249); 2 males (SL 1.67 and 2.10 mm), Las Amacas and El Pinto, Bahía de Topolobampo, Sinaloa (25°32’05’’N, 109°05’01’’W), 26 Nov 2004, 0–0.5 m ( LACM CR 2004-034); 1 male (SL 2.57 mm) and 1 female (SL 2.19 mm), Las Amacas and El Pinto, Bahía de Topolobampo, Sinaloa (25°32’05’’N, 109°05’01’’W), 26 Nov 2004, 0–0.5 m (CNCR-26661).

Additional material. 2 males (SL 2.83 and 3.45 mm) and 4 ovig. females (SL 2.62–3.10 mm), Bahía La Choya, Puerto Peñasco, Sonora 8 Sep 1983 (UAZ-1519); 2 males (SL 3.20 and 3.35 mm), Bahía La Choya, Sonora, (31°20’36’’N, 113°38’40’’W), 6 Mar 2007, (EMU-9247); 23 specimens in shell (NS, NM), Bahía La Choya, Sonora (31°20’36’’N, 113°38’40’’W), 6 Mar 2007 (EMU-9248); 11 males (SL 1.45–3.00 mm) and 2 females (SL 2.00 mm), Estero de La Cruz, Bahía Kino, Sonora (28°47’32’’N, 111°54’48’’W), 7 Mar 2007 (EMU- 9251); 5 males (SL 1.50–2.70 mm), Isla Alcatraz, Bahía Kino, Sonora (28°48’43’’N, 111°57’42’’W), 8 Mar 2007 (EMU-9253); 2 males (SL 1.30 and 2.20 mm), Isla Alcatraz, Bahía Kino, Sonora (28°48’56’’N, 111°57’51’’W), 8 Mar 2007 (EMU-9254); 1 female (SL 1.08 mm), Bahía de Bacochibampo, Guaymas, Sonora, 2 Sep 2001 (EMU- 9522); 12 males (SL 1.47–3.07 mm), 7 females (SL 1.33–2.33 mm), and 7 specimens in shell (NS, NM), Punta Prieta, Bahía de Topolobampo, Sinaloa, 25 Nov 2004, oyster dredge, 0.5–1.0 m (EMU-9523); 2 males (SL 2.20 and 2.46 mm), 2 females (SL 1.76 and 2.17 mm), and 6 specimens in shell (NS, NM), Ensenada El Pabellón, Sinaloa St. 11 (24°29’12’’N, 107°31’16’’W), 13 Dec 1990, beam trawl, 2.5 m (EMU-9524); 1 female (SL 2.20 mm), Las Ratas, Ensenada El Pabellon, Sinaloa, St. 1A (24°29’56’’N, 107°41’19’W), 5 Mar 1991 (EMU-9525); 11 specimens in shell (NS, NM), La Figueroa, Ensenada El Pabellón, Sinaloa (24°28’49’’N, 107°44’W), 22 Jun 1991, 0.8–1 m, sand (EMU-9526); 2 males (SL 2.17 and 2.59 mm) and 1 female (SL 2.58 mm), Ensenada El Pabellón, Sinaloa (24°24’12’’N, 107°34’15’’W), 23 Jun 1991, 2 m, trawl (EMU-9527); 4 males (SL 2.26–3.21 mm), 2 females (SL 1.46 and 1.88 mm), and 2 ovig. females (SL 1.60 and 1.78 mm), Las Ventanas, Ensenada El Pabellón, Sinaloa (24°28’07’’N, 107°37’32’’W), 6 Mar 1991, push net (EMU-9528); 1 male (SL 1.33 mm) and 1 female (SL 1.70 mm), Ensenada El Pabellón, Sinaloa (24°24’12’’N, 107°34’15’’W), 23 Jun 1991, 2 m, trawl (EMU-9529); 1 male (SL 1.51 mm) and 4 specimens in shell (NS, NM), La Palma-Altata, Sinaloa, serie 28, St. 15 (EMU-9530); 3 males (SL 2.14–2.54 mm), Isla Capultita, Ensenada El Pabellón, Sinaloa (24°28’08’’N, 107°42’49’’W), 2 May 1991 (EMU-9531); 2 males (SL 1.43 mm), Las Ratas, Ensenada El Pabellón, Sinaloa, serie 72, St.1 (24°29’56’’N, 107°41’19’’W), 22 Jun 1991, 0.40 m (EMU-9532); 1 male (SL 1.46 mm) and 2 ovig. females (SL 1.04 mm), Bahía de Mazatlán, Sinaloa (23°12’12’’N, 106°25’57’’W), BBMAZ cruise C13 B/E FC1, 8 Jul 1980, (EMU-9533); 1 ovig. female (SL 1.39 mm) and 5 specimens in shell (NS, NM), Puerto Viejo, Bahía de Mazatlán, Sinaloa (23°13’36’’N, 106°27’28’’W), 20 Oct 2006, oyster dredge, 4 m, sand (EMU-9534).

Description. Shield ( Fig. 1 View FIGURE 1 A) as long as broad, dorsal surface with numerous toothed tubercles, spines, spinules, and tufts of long setae; well marked, anterior median concavity. Rostral tooth short, obtusely triangular, weakly produced, shorter than lateral projections; lateral projections obtuse, each armed with small marginal spine, reaching bases of ocular acicles. Margin between rostrum and lateral projections slightly concave or straight. Anterolateral margins sloping; anterolateral angle with 1 submarginal strong spine. Branchiostegites each with row of small to moderately strong spines on anterodorsal distal margin, partially concealed by tufts of long setae; distal margin with long setae.

Ocular peduncles ( Fig. 1 View FIGURE 1 A) long, cylindrical or slightly compressed in middle; length 0.70 times width of shield; dorsomesial margin with row of short setae. Cornea small, not dilated, diameter about 0.20 peduncular length. Ocular acicles long, subtriangular or subrectangular, mesial margins contiguous, each armed with 2–4 small spines on lateral margin and tufts of long plumose setae, terminating in 2 or 3 spines; inner margin ocasionally with one submarginal small spine at subdistal margins.

Antennular peduncles ( Fig. 1 View FIGURE 1 A) long, overreaching ocular peduncles by 0.50 length of ultimate segment when fully extended; ultimate and penultimate segments unarmed; basal segment with ventromesiodistal and laterodistal margins each bearing 1 small spine and tufts of setae.

Antennal peduncles long, reaching half of cornea or slightly overreaching ocular peduncles, with supernumerary segmentation. Fifth segment unarmed, with longitudinal row of long setae on dorsolateral margin. Fourth segment with one small spine on dorsodistal margin. Third segment with rounded ventral margin and with 1–3 spines on ventromesial distal angle and long setae. Second segment with dorsolateral distal angle produced, terminating in strong bifid spine; lateral margin with 1 or 2 small spines; dorsomesial distal angle terminating in strong spine; mesial margin with tufts of setae. First segment with 1 small spine on lateral distal margin. Antennal acicles long or moderately long, straight or slightly curved, reaching 0.70 length of ocular peduncles; mesial margin with 4 or 5 spines and tufts of long setae, lateral margin unarmed, terminating in bifid spine. Antennal flagella short, not exceeding length of chelipeds, each article with long and paired setae ventrally.

Mandible with 3-segmented palp. Maxillule ( Fig. 2 View FIGURE 2 A) with proximal endite subquadrate; distal endite subrectangular, enlarged distally; endopod with one apical seta on weakly produced internal lobe, external lobe well developed, recurved, about 0.80 length of endopod, exterobasal angle with 2 or 3 long setae. Maxilla ( Fig. 2 View FIGURE 2 B) with endopod moderately long, slightly exceeding scaphognathite in distal extension. First maxilliped ( Fig. 2 View FIGURE 2 C) with endopod moderately short, not reaching distal end of basal segment of exopod; proximal segment of exopod subtriangular, tapering distally; flagellum short, distally laminar, with long plumose setae; epipod well developed. Second maxilliped ( Fig. 2 View FIGURE 2 D) with basis-ischium fusion incomplete. Third maxilliped ( Fig. 2 View FIGURE 2 E) with basis-ischium fusion complete; coxa with one large spine at ventrodistal margin, basis with 3 spines or denticles partially concealed by tufts of long setae; ischium with well developed crista dentata, without accesory tooth; merus with ventral margin unarmed, dorsodistal margin with minute spine; carpus, propodus and dactyl unarmed.

Chelipeds ( Fig. 1 View FIGURE 1 A, B) short, slightly unequal, left larger than rigth and differing somewhat in armature. Dactyls 1.10–1.20 times longer than palms, each terminating in large corneous-tipped claw overlapped by tip of fixed fingers; dactyls and fixed fingers equal in breadth; dorsal surface with few small spines accompanied by tufts of long setae; dorsomesial margin with row of strong, corneous-tipped spines decreasing in size distally; mesial surface with rows of single, bifid or trifid spine-like tubercles or spines accompanied by tufts of long setae; ventral surface with row of tubercles acompanied by tufts of long setae; cutting edge with calcareous teeth interspaced with corneous denticles. Palms arcuate on dorsomesial margin, latter armed with 4–6 (usually 5), strong, corneoustipped spines and tufts of long setae; dorsal surface with 3–4 (left) or 4–5 (right) longitudinal rows of corneoustipped spines, smaller than dorsomesial spines, more densely set in fixed finger surface, accompanied with tufts of long setae; dorsolateral margin with row of strong, corneous-tipped spines decreasing in size proximally and distally; mesial, lateral and ventral surfaces each with irregular longitudinal row of strong granules or spine-like tubercles; fixed finger ending in corneous-tipped claw, dorsal surface with 2 or 3 irregular longitudinal rows of conical spines accompanied with tufts of long setae; cutting edge with calcareous teeth. Carpi 0.55 to 0.67 length of meri; dorsal surfaces each with few corneous-tipped spines, distal margin with corneous-tipped spines and tufts of long setae, one strong spine near articulation with palm; dorsomesial margins each with 4–6 (usually 5) corneous-tipped conical spines acompanied with tufts of long setae; dorsolateral margins each with 4 corneous-tipped conical spines; mesial and lateral surfaces with tubercles or granules accompanied with tufts of stiff setae. Meri long, 0.80–1.00 times length of palm; dorsal margins each with row of tubercles proximally, becoming corneous-tipped spines distally, the latter extending on lateral surfaces, and tufts of long stiff setae; distal and subdistal margins each with strong, corneous-tipped spines and tufts of long stiff setae; mesial faces smooth, with some tufts of long setae proximally and scattered granules distally; distal margins each with tufts of long stiff setae; ventromesial margins with teeth or tubercles and tufts of long plumose setae; lateral faces with numerous granules or tubercles, larger anteriorly, and tufts of long plumose setae; ventrolateral margins with tubercles and tufts of long plumose setae; ventral surfaces with scarse tubercles accompanied by tufts of short setae. Ischia with granules or teeth on ventromesial margin and tufts of long plumose setae.

Second and third pereopods ( Fig. 3 View FIGURE 3 A–D) long, slender and setose on dorsal and ventral margins, exceeding chelipeds by 0.50 length of dactyl. Dactyls long, 1.33 times length of propodi, ending in large corneous claw; dorsal surfaces each with row of corneous-tipped spines proximally, decreasing in size distally (second) or with row of spine-like granules decreasing in size distally (third), accompanied by tufts of long stiff setae; dorsomesial and dorsolateral margins each with irregular row of small, spine-like granules, partially concealed by tufts of long stiff setae (second) or only with tufts of long stiff setae (third); mesial surfaces each with 2 irregular longitudinal rows of small, corneous-tipped spines, largest proximally, accompanied by tufts of long stiff setae; ventromesial margins with tufts of long setae; lateral surfaces each with longitudinal smooth sulcus flanked by tufts of moderately long setae; ventrolateral margins with tufts of long setae; ventral margins each with row of corneous spines increasing in size distally. Propodi moderately long, 1.25–1.30 times length of carpi; dorsal surface with row of large, corneoustipped spines (second) or with small, spine-like tubercles accompanied by tufts of long stiff setae (third); mesial and lateral surfaces rugose or with irregular longitudinal rows of flattened tubercles bearing tufts of long setae; dorsomesial and dorsolateral margins each with row of small, corneous-tipped spines acompanied by tufts of long stiff setae; ventral surfaces with flattened granules or tubercles bearing tufts of long stiff setae. Carpi short, 0.75–0.90 length of meri; dorsal surfaces each with double irregular row (second) or single row (third) of large or moderately large corneous-tipped spines accompanied by tufts of long stiff setae; mesial surfaces each with 2 irregular longitudinal rows of tufts of moderately long setae; lateral surfaces each with 2 longitudinal rows of tufts of short setae, distal margin with some small spines. Meri long, compressed laterally; dorsal surfaces each with row of small corneous-tipped spines (second) or double row of small, spine-like flattened tubercles (third) concealed by tufts of long plumose setae; mesial surfaces smooth, with few tufts of short stiff setae or bristles; lateral surfaces each with numerous small granules or tubercles accompanied by tufts of long stiff setae; ventral surfaces each with double row of corneous tubercles or teeth (second) or only flattened granules or tubercles (third) concealed by tufts of long plumose setae. Ischia each with row of small granules or spines on ventromesial margin, dorsodistal margins with strong, corneous-tipped spine (second) or row of small granules or spines (third) and tufts of long, stiff plumose setae.

Sternite of third pereopods with bilobate, anterior lobe, each lobe with tufts of long stiff setae.

Fourth pereopods ( Fig. 3 View FIGURE 3 E) weakly semichelate; dactyl short, setose, with 1 or 2 moderately strong spines posterior to preungual process; preungual process well developed, almost as long as dactyl, covered apically by very short setae; propodi with propodal rasp consisting of 3 or 4 rows of oval corneous scales. Carpus and merus unarmed, with tufts of long setae on dorsal margin. Fifth pereopods chelate; dactyl with 2 or 3 rows of corneous denticles; propodus with well developed rasp.

Male first and second pleopods modified as gonopods. First pleopod ( Fig. 1 View FIGURE 1 D, E) with row of long setae on mesial margin of basal lobe, superior mesial angle with tufts of long setae, lateral margin of basal lobe naked or with 2 or 3 long setae proximally; inferior lamella with row of long setae on lateral margin, distal margin with row of simple, bifid or trifid, curved corneous spines extending on mesial face; external lobe subtriangular, exceeding inferior lamella in distal extention, naked; inner lobe reduced or vestigial, mesial margin with tuft of short setae proximally. Second pleopod ( Fig. 1 View FIGURE 1 F) with basal segment usually naked; endopod with few long setae; appendix masculina strongly twisted, lateral and distal margins and ventral face with long setae. Pleopods 3–5 unpaired, exopod well developed, endopod vestigial or absent.

Female with paired gonopores; lacking first pleopods; pleopods 2–4 on left side with both rami well developed; pleopod 5 as in male. Brood pouch represented by row of long setae posterior to pleopod 4.

Sixth pleonal tergite subrectangular ( Fig. 1 View FIGURE 1 G), well calcified, divided in 3 areas by sulci, anterior area larger; dorsal face with scarce granules or crenulations and tufts of long setae; anterior margin rounded, posterior margin straight; posterolateral margins fringed with long setae, left posteriorly oblique.

Uropods and telson asymmetrical. Telson ( Fig. 1 View FIGURE 1 G) with posterior lobes subrectangular to subquadrate, left larger than right; separated by small median, shallow cleft; posterior margin of lobes each armed with 7 or 8 strong, corneous-tipped spines, increasing in size towards lateral margins; lateral margin of left lobe usually with 2 strong spines. Anterior lobe unarmed, usually with 1 granule or crenulation distally and tufts of long setae on lateral margins.

Color. In life: specimens collected in estuaries present the following coloration. Pleon greenish-blue. Carapace purple over white or cream background. Shield and ocular acicles olive. Antennal and antennular segments, and antennal flagella transparent. Ultimate and penultimate antennular segments each with two longitudinal reddishbrown stripes, one on dorsomesial and another on ventromesial margins. First antennal segment and antennal acicle whitish. Antennal flagella with one longitudinal brown stripe on ventral margin. Ocular peduncles light pink. Cornea light brown or honey. Third maxillipeds transparent with merus, carpus, propodus and dactyl each with proximal brown band. Chelipeds and ambulatory legs with orange setae. Chelipeds with movable and fixed fingers white, movable fingers with proximal brown band. Palms and carpi with dorsal and half of lateral surfaces brown, ventral surface white. Meri with dorsal surface olive and proximal half of lateral surface brown, mesial surface with one subdistal blue spot. Ambulatory legs with dactyls cream lateraly, olive dorsally, each with brown band proximally. Propodi olive over whitish background, with proximal brown band. Carpi light olive with dorsal surface dark-green. Meri olive laterally, dorsal surface light brown, mesial surface with one blue spot.

Specimens collected in the intertidal and subtidal zones present the following coloration. General coloration orange, with ocular peduncles pink. Chelipeds with a blue spot on inner side of meri. This color pattern agrees with the description provided by Westervelt (1967) for Paguristes sp.

Specimen fixed over a long period of time. Shield whitish or cream; chelipeds, pereopods and remainder of body cream or light orange. A large, uncalcified area can be seen on the inner surface of merus of chelipeds, which appears reddish or purple under light.

Habitat. Areopaguristes lemaitrei sp. nov. is abundant in bays and estuaries throughout its range, on sand and muddy-sand, between 0 and 4 m depth. Specimens examined use several species of gastropod shells, but more frequently Cerithium maculosum Kiener, 1841 .

Distribution. Eastern coast of the Gulf of California, from Bahía La Choya, Puerto Peñasco, Sonora, to Estero de Urias, Mazatlán, Sinaloa, Mexico.

Etymology. The species name honors Rafael Lemaitre from Smithsonian Institution National Museum of Natural History, in recognition of his enormous contributions to the study of hermit crabs, and the countless occasions on which he has shared his experience and knowledge of anomurans with us; used as a noun in the genitive case.

Remarks. The material reported as Paguristes sp. by Westervelt (1967) is from Puerto Peñasco, one of the many localities at which A. lemaitrei sp. nov. was collected. The color pattern provided by Westervelt (1967) fits well with the color of the material of A. lemaitrei sp. nov. collected in the intertidal zone on sandy beaches during this study and we believe that both are conspecific. Based on the color pattern, the reference to Paguristes sp. by Snyder-Conn (1980: 277, key) might also refer to A. lemaitrei sp. nov. or to the other new species described herein.

Among the species of Areopaguristes , A. lemaitrei sp. nov. shows major morphological similarities with A. mclaughlinae ( Ayón-Parente & Hendrickx, 2006) , both species having contiguous and multispinous ocular acicles, antennular and antennal peduncles of equal length, and antennal flagella bearing long setae ventrally. The armature of the chelipeds is also very similar, but in A. lemaitrei sp. nov. the spines on the palm and fingers are corneoustipped while in A. mclaughlinae they are obtuse. Areopaguristes lemaitrei sp. nov. is also distinguished from A. mclaughlinae by the shape of the rostrum, which is broadly rounded and shorter than lateral projections in the former vs. triangular and equal in length to lateral projections in the latter, and by the antennal acicles, unarmed on lateral margin in the former vsarmed with 1 or 2 small spines in the latter. Also, the male first pleopod in A. lemaitrei sp. nov. features a subtriangular external lobe, rather than a subrectangular lobe in A. mclaughlinae . The habitat occupied by these two species also differs. Areopaguristes lemaitrei sp. nov. occurs at intertidal or shallow depths (0–4 m), while A. mclaughlinae is subtidal (5–27 m). The colour pattern of these two species is also different. In A. mclaughlinae the shield bears reddish-brown spots on a cream background; ocular peduncles white; chelipeds reddish-brown with dactyl and fixed finger white; ambulatory legs with dactyl and propodus white, each with narrow, reddish-brown band proximally; carpi and meri reddish-brown on dorsal surface, lateral and ventral surfaces white ( Ayón-Parente & Madrid-Vera 2009).

Areopaguristes lemaitrei View in CoL sp. nov. also shows some superficial resemblances with Paguristes praedator Glassell, 1937 View in CoL , including in the shape of the rostrum and the antennal flagellum. In P. praedator View in CoL , the ocular peduncles are proportionally longer and more slender, and the ocular acicles are separated and bear a single spine, while in A. lemaitrei View in CoL sp. nov. these are contiguous and multispinous.