TWO NEW HAIRY SPECIES OF CAPRELLA (AMPHIPODA) FROM THE STRAIT OF GIBRALTAR, WITH A REDESCRIPTION OF CAPRELLA GRANDIMANA

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1 JOURNAL OF CRUSTACEAN BIOLOGY, 21(4): , 2001 TWO NEW HAIRY SPECIES OF CAPRELLA (AMPHIPODA) FROM THE STRAIT OF GIBRALTAR, WITH A REDESCRIPTION OF CAPRELLA GRANDIMANA José M. Guerra-García, J. Emilio Sánchez-Moyano, and J. Carlos García-Gómez Laboratorio de Biología Marina, Departamento de Fisiología v Biología Animal, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, E-41080, Sevilla, Spain (corresponding author (JMG-G) jmguerra@cica.es) ABSTRACT Two new hairy species of caprellid amphipod, Caprella monai and Caprella takeuchii, are described based on specimens from the Strait of Gibraltar. Caprella takeuchii was found on algae and intertidal sediment under rocks from Tarifa, Southern Spain, while Caprella monai was collected clinging to the hydroid Nemertesia antennina and living on sediments from Ceuta, northern Africa. The most outstanding characteristic for both species is the presence of dense setae along the body. Caprella takeuchii is very similar to Caprella acanthifera Leach, 1814, except for the presence of dense setae in the male and the differences in upper and lower lips. Caprella monai is closely related to the poorly known Caprella grandimana Mayer, In the present paper we also redescribe C. grandimana on the basis of specimens from the Strait of Gibraltar. Since 1986, the Laboratorio de Biología Marina de la Universidad de Sevilla has been developing research programmes on benthic animal communities from the Strait of Gibraltar. An important part of these studies has focused on the amphipod fauna. The first research projects were conducted in Algeciras Bay (Southern Spain, Iberian side of the Strait of Gibraltar) dealing with Gammaridea (Conradi et al., 1995; Conradi et al., 1997; Conradi and López-González, 1999) and Caprellidea (Sánchez-Moyano et al., 1995a, b). The most recent studies have focused on the Caprellidea from Ceuta (North African side of the Strait of Gibraltar) (Guerra-García and Takeuchi, in press). In 1991 during a study of the caprellid fauna of Tarifa Island, Southern Spain, numerous specimens of a caprellid species close to Caprella acanthifera Leach, 1814, were collected from several species of algae in the intertidal zone. Afterwards, in 2000, many individuals of the same species were found living in sediment surface and under rocks near Tarifa harbour. Detailed examination revealed that all of these specimens belonged to a new species, described herein as Caprella takeuchii n. sp. Furthermore, during a sampling survey of the hydroids from Ceuta, a striking specimen was collected attached to the hydroid Nemertesia antennina (Linnaeus, 1758). Another identical specimen was recently collected from sediment, described here as Caprella monai n. sp. In this paper, we also redescribe Caprella grandimana Mayer, This species is, so far, a Mediterranean endemic (Krapp- Schickel, 1993). After the morphological study of specimens of C. grandimana from the Strait of Gibraltar, some characteristics not included in previous descriptions and several differences with these descriptions were observed. MATERIALS AND METHODS The specimens of Caprella takeuchii n. sp. and C. grandimana Mayer, 1882, were collected in the intertidal area at low tide. Caprella monai n. sp. was collected by SCUBA diving at about 30 metres depth, attached to the hydroid Nemertesia antennina and from sediment with a hand core. The samples were fixed using Formalin 4% in sea water solution and placed in ethyl alcohol 70%. Selected specimens were dissected under a stereomicroscope; permanent mounts were made in polyvinyl-lactophenol. All the figures have been drawn with the aid of a camera lucida. Specimens of the three species have been deposited in the Museo Nacional de Ciencias Naturales de Madrid (MNCN), Spain. SYSTEMATICS Family Caprellidae White, 1847 Genus Caprella Lamarck, 1801 Caprella grandimana Mayer, 1882 Figs. 1 4 Caprella grandimana Mayer, 1882, p. 43, pl. 1, fig. 5, pl. 2, figs , pl. 4, figs ; Cavedini, 1982, p. 501, fig. 2; Krapp-Schickel, 1993, pp , fig

2 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1015 Fig. 1. Caprella grandimana Mayer, Lateral view: a, male; b, female. Scale bar: 1 mm. Caprella acanthifera var. grandimana Mayer, 1890, p. 47. Caprella acanthifera ssp. grandimana Carausu and Carausu, 1959, p Caprella hirsuta f. longimana Chevreux, 1913, p. 5, fig. 1; McCain and Steinberg, 1970, p. 23. Material Examined. 20 mature males, body length: mean ± SD = 6.78 ± 0.58 mm, range = mm, 10 mature females, body length 4.02 ± 0.39 ( ), June 1991, clinging to algae from intertidal pools, Tarifa Island (36 N, W), Cádiz, Spain, coll. J. E. Sánchez-Moyano. Diagnosis. Body smooth except pereonites 5 7, carrying small humps. Gnathopod 2 inserted on posterior end of pereonite 2 in males and on anterior end in females. Gnathopod 2 in males covered with fine setae, propodus rounded. Inner margin of gnathopod 2 dactylus with 1 thickened hump medially. Propodus of pereopods 5 7 carrying pair of medial grasping spines and some more distal accessory spines. Abdominal appendages 1-articulate. Redescription. Male a from Tarifa Island (36 N, W). Body length: 7.69 mm. Head rounded, without rostrum or spines. Body smooth except pereonites 5, 6, and 7 where small tubercles are present following the formula 1, 2, 2. Pereonite 2, 2 times longer than pereonite 3. Pereonites 3, 4, and 5 subequal. Pereonites 6 and 7 shorter, about half of pereonite 3. Gills oval, length about 2 times width. Antenna 1 about half body length; flagellum 10-articulate. Antenna 2 slightly shorter than half of antenna 1; swimming setae absent. Upper lip densely pubescent. Inner and outer lobes of lower lip well developed, round, pubescent on apicomedial margins. Mandible without palp. Incisor 5-toothed, lacinia mobilis 4-toothed. Row of 3 plumose setae on left mandible, 2 on right one. Molar process well developed, with 1 simple seta. Molar flake (see Laubitz, 1993) on right molar. Maxilla 1 without inner lobe; outer lobe with 5 forked, 2-pronged sharp spines distally (see Krapp-Schickel and Vader, 1998), fine setae in inner margin. Palp 2-articulated, distal article with 6 spines on end and row of 6 setae on ventral surface. Inner lobe of maxilla 2 only a little shorter than outer lobe, oval, with 2 rows of numerous simple setae on apicomedial margin and 1 plumose seta proximally; outer lobe rectangular, with 2 rows of setae on apical margin. Inner plate

3 1016 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Fig. 2. Caprella grandimana Mayer, a d, male. a, antenna 1; b, antenna 2; c, gnathopod 1; d, gnathopod 2. e, female gnathopod 2. Scale bars: A: 1 mm (a); B: 0.3 mm (b); C: 0.3 mm (c); D: 1 mm (d); E: 0.3 mm (e).

4 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1017 Fig. 3. Caprella grandimana Mayer, a d, male. a, pereopod 5; b, pereopod 6; c, pereopod 7; d, abdomen; e, female abdomen. Scale bars: A: 1 mm (a, b, c); B: 0.2 mm (d, e). of maxilliped rectangular, as big as outer plate, with 3 teeth and several plumose setae on apical margin. Outer plate small, subequal to article 1 of palp in length, with 1 tooth and 2 simple setae distally. Palp 4-articulate. Article 1 short, article 2 and 3 subequal in length, article 4 with rows of setulae on grasping margin. Gnathopod 1 ischium and merus short, with setae on ventral surface. Carpus expanded ventrally, bearing numerous setae. Palm of propodus with pair of grasping spines proxi-

5 1018 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Fig. 4. Caprella grandimana Mayer, Male. a, upper lip; b, lower lip; c, maxilliped; d, right mandible; e, left mandible; f, maxilla 1; g, maxilla 2. Scale bars: 0.2 mm. A: (a, b); B: (c); C: (d, e, f, g).

6 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1019 mally. Dactylus serrated and distally bifid. Gnathopod 2 inserted on posterior end of pereonite 2, covered entirely with fine setae. Basis as long as pereonite 2, longer than propodus. Merus about 1.5 times ischium. Carpus short, about half ischium in length. Propodus round, length about 1.3 times width. Palm of propodus convex, with 1 very acute projection. Short triangular process distally. Dactylus slightly thickened medially. Pereopods 5 7 increasing in length respectively, but morphologically similar. Basis without carina. Palm of propodus bearing pair of medial grasping spines and some more distal accessory spines. Penes situated laterally. Abdomen consisting of pair of appendages, pair of lateral lobes, and single dorsal lobe. Abdominal appendages 1-articulate, although constrained medially and with short setae on end. Female b from Tarifa Island (36 N, W). Body length 4.1 mm. Pereonites 2 5 subequal. Dorsal small tubercles present only on pereonites 6 and 7. Flagellum of antenna 1, 7-articulate. Gnathopod 2 inserted on anterior half of pereonite 2. Propodus 2 times as long as broad, without fine setae on surface. Median acute tooth lacking on palm of propodus. Three large grasping spines on proximal end. Dactylus curved. Abdomen with pair of lateral lobes and single dorsal lobe, without appendages. Male a and female b from Tarifa Island have been deposited with number MNCN 20.04/4652. Remarks. The taxonomic location of Caprella grandimana has not been very clear since its original description. After the description as a new species by Mayer (1882) this species has been considered as a variety or subspecies of Caprella acanthifera Leach, 1814 (Mayer, 1890; Carausu and Carausu, 1959). In fact, C. grandimana is very similar to some species of the C. acanthifera group, especially to C. cavediniae, recently described by Krapp-Schickel and Vader (1998) (Table 1). Chevreux (1913) and Mc- Cain and Steinberg (1970) considered C. grandimana as the form longimana of C. hirsuta Mayer, Finally, Cavedini (1982) considered again C. grandimana as a different species and established the synonymy between C. grandimana and C. hirsuta f. longimana. This consideration has been maintained in successive papers (Krapp-Schickel, 1993; Bellan-Santini and Ruffo, 1998). After our redescription based on specimens from the Strait of Gibraltar we agree with Cavedini (1982) in considering C. grandimana as a different species. The male gnathopod 2 is clearly different from the other species, and pereonite 2 is clearly longer than pereonite 3 (Table 1). In this paper we complete the previous descriptions of C. grandimana, including detailed figures. The most important difference between our description and the previous ones is the presence of 1-articulate abdominal appendages in the specimens from the Strait of Gibraltar. In specimens from Napoli, Italy (see figures in Mayer, 1882) and from Cesarea, Israel (see figures in Cavedini, 1982, and Krapp-Schickel, 1993) abdominal appendages of the male abdomen are clearly 2- articulate. Furthermore, the small tubercles on the body surface of specimens from Gibraltar are lacking in specimens from Napoli and Cesarea. Nevertheless, these differences could be attributed to morphological intraspecific variation. Caprella monai, n. sp. Figs. 5 8 Type Material. Holotype: mature male, 4.3 mm in length (MNCN 20.04/4655) from the hydroid Nemertesia antennina found on Ceuta (35 55 N, 5 21 W), 25 m, September 1999, coll. J. Rodríguez El mona. Paratype: 1 mature male, 4.2 mm in length collected from sediment (medium and gross sands), Ceuta (35 53 N, 5 19 W), 15 m, August 2000, coll. J. M. Guerra-García. Diagnosis. Body smooth, densely covered with setae, especially developed on pereonites 3 and 4. Palm of gnathopod 2 with deep semicircular excavation filled with membranous sac. Inner margin of gnathopod 2 dactylus with 1 thickened hump medially. Distal accessory spines on propodus of pereopods lacking. Abdominal appendages 2-articulate. Description. Holotype male (MNCN 20.04/ 4655). Body length 4.3 mm. Head skull - like (see Krapp-Schickel and Vader, 1998), regularly convex, without rostrum or spines. Body smooth, densely covered with setae, especially developed on surface of pereonites 3 and 4. Pereonite 1 fused with head, short. Pereonites 2, 3, and 4 subequal. Gills oval, length about 2.5 times width. Antenna 1 about 3/4 body length, with 9 articles in flagellum; peduncular articles

7 1020 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Table 1. Comparison of selected characteristics in several species of Caprella similar to C. monai n. sp. and C. takeuchii n. sp., based on adult males. Information was taken from text and figures included in Krapp-Schickel (1993) and Krapp-Schickel and Vader (1998). C. acanthifera C. stella C. cavediniae C. grandimana C. monai C. takeuchii Body length 6 9 mm 3 5 mm 4 7 mm mm 4.3 mm mm Setae covering body Absent Absent Absent Only on gnathopod 2 Abundant all over body Abundant all over body surface except gills and except gills, pereopods pereopods and pereonites 6 7. Gnathopod 2 and pereonites 2 3 especially setose Habitus dorsally Many tubercles Few rounded humps Few rounded humps Few rounded humps Without tubercles or Many tubercles humps Pereonite lengths 2 = 3 > 4 > 5 > 6 = 7 2 = 3 = 4 > 5 > 6 = 7 2 = 3 > 4 > 5 > 6 = 7 2 > 3 > 4 = 5 > 6 = 7 2 = 3 = 4 > 5 > 6 = 7 2 = 3 > 4 > 5 > 6 > 7 Insertion of gnathopod About middle Middle Middle Posterior end Middle Middle 2 on pereonite 2 Gnathopod 2 propodus lenght/width ratio Gnathopod 2 palm Semicircular Shallow to U-shaped Semicircular Semicircular Semicircular Semicircular excavation Gnathopod 2 dactylus 2 thickened humps Crenulated Thickened distally Thickened medially Thickened medially 2 thickened humps inner margin Pereopods 6, 7 With strong spines No spines No spines With a few weak spines No spines With strong spines propodus hind-margin Shape of gills Elongate Oval Oval Oval Oval Elongate Teeth in maxilliped 3 1 (although not (although not lobes (Inner-Outer) clearly described) clearly described) Lateral surface of lobes Without setae Without setae Without setae Without setae Without setae With dense setae in upper and lower lips Abdominal appendages 1 article, with short 2 articles, the distal one 2 articles, the distal one 1 article, with short 2 articles without setae 1 article, with short setae on end with short setae on end with short setae on end setae on end setae on end Ecology Shallow-water depth, On starfish, m Shallow depth, algae, Shallow depth, intertidal On hydroids, m, Shallow waters, high detritus content hydroids, no detritus zone, algae high detritus content, intertidal zone, algae, sediment sediment below intertidal rocks

8 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1021 Fig. 5. Caprella monai n. sp. Male, lateral view. Scale bar: 1 mm. densely covered with fine setae. Antenna 2 slightly shorter than half antenna 1; swimming setae absent; peduncular articles 3 and 4 with fine setae; article 2 of flagellum very short. Upper lip semicircular, symmetrically bilobed, pubescent apically. Inner and outer lobes of lower lip round, with dense setules close to margin. Mandibular process strong, bordered by row of round teeth. Incisor 5- toothed, lacinia mobilis 4-toothed. Row of 3 plumose setae on left mandible, 2 on right one. Molar flake on right molar. Maxilla 1 outer lobe with 7 forked, 2-pronged spines distally, many dense, fine setae in inner margin. Palp with 2 articles, distal one with 4 strong spines distally and row of 8 setae medially. Maxilla 2 outer lobe approximately same size as inner one, with 2 rows of simple setae on end; inner lobe with plumose setae distally and marginally, proximally with dense, short setae. Inner plate of maxilliped bigger than outer plate, with 6 teeth and several plumose setae on apical margin and many short, fine setae on inner margin. Outer plate with 1 tooth and several simple setae distally. Palp 4-articulate. Article 1 short; article 2 almost as wide as long, covered with numerous long setae on medial margin; article 3 slender; article 4 with rows of setulae on grasping margin. Basis of gnathopod 1 same size as ischium to carpus combined. Carpus with long setae. Propodus twice longer than carpus, length about 2 times width; palm carrying pair of proximal strong spines. Basis, ischium, and carpus covered by short fine setae. Dactylus distally bifid. Gnathopod 2 inserted at middle of pereonite 2, covered with fine setae. Basis as long as pereonite 2, longer than propodus. Carpus short, about half of merus in length. Ischium and merus subequal. Palm of propodus convex, with 1 big projection delimiting concavity filled with membranous sac; triangular process distally. Dactylus inner margin with 1 hump medially. Pereopods 5 and 6 with pair of grasping spines at propodus palm. Distal accessory spines lacking. Dactylus with 1 plumose seta. Basis without carina. Pereopod 7 missing in holotype.

9 1022 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Fig. 6. Caprella monai n. sp. Male. a, antenna 1; b, antenna 2; c, gnathopod 1; d, gnathopod 2. Scale bars: A: 1 mm (a); B: 0.5 mm (b); C: 0.2 mm (c); D: 0.2 mm (d).

10 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1023 Fig. 7. Caprella monai n. sp. Male. a, pereopod 5; b, pereopod 6; c, abdomen. Scale bars: A: 0.3 mm (a, b); B: 0.1 mm (c). Penes short, situated laterally. Abdomen with pair of appendages, pair of lateral lobes, and single dorsal lobe. Abdominal appendage 2-articulate, smooth. Distal article slender, length about 2 times width. Dorsal lobe with pair of plumose setae. Etymology. Caprella monai n. sp. is dedicated to Juan Rodríguez El mona. He provided us the type material and assisted our sampling programmes in Ceuta s coast with his ship Gema del Mar. Remarks. Caprella monai n. sp. is similar to Caprella grandimana Mayer, 1882, although it also shares some characteristics with the species of the C. acanthifera-group (see Krapp-Schickel and Vader, 1998) (Table 1). The most important differences between C. monai and the rest of the close species are

11 1024 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Fig. 8. Caprella monai n. sp. Male. a, upper lip; b, lower lip; c, maxilliped; d, right mandible; e, left mandible; f, maxilla 1; g, maxilla 2. Scale bars: 0.1 mm. A (a, b); B (c); C (d, e, f, g).

12 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1025 Fig. 9. Caprella takeuchii n. sp. Lateral view: a, male; b, female. Scale bar: 1 mm. as follows: the presence of setae covering the whole body surface, the body surface completely smooth, and the presence of five teeth on the inner lobe of the maxilliped. In C. acanthifera Leach, 1914, adult specimens often are densely overgrown on gnathopods or body by filiform algae, which easily might be confused with setae (Krapp- Schickel and Vader, 1998). However, C. monai has true setae, especially developed on pereonites 3 and 4. These setae let the specimen be camouflaged among the branches of the hydroid Nemertesia antennina. This could be the reason why this species has not been reported before in Mediterranean or Atlantic waters. The present material, only two specimens, is, however, too limited to generalise conclusions. It would be convenient to find more specimens in order to study ecological aspects and intraspecific morphological variation. Caprella takeuchii, n. sp. Figs Type Material. Holotype: male, 8 mm in length, collected from sediment surface under intertidal rocks at low tide, found on Tarifa (36 05 N, 5 36 W), Cádiz, Spain, January 2000, coll. J. M. Guerra-García. Allotype female, 3.97 mm in length, and paratypes (3 males and 3 females) collected together with holotype. Type material (holotype male, allotype female, and paratypes) have been deposited in the Museo Nacional de Ciencias Naturales de Madrid, Spain, with number MNCN 20.04/4656. Additional Material Examined. 5 males, body length: mean ± SD = 6.99 ± 0.44 mm, range = mm, clinging to the alga Cladophora sp. on the intertidal zone of Tarifa Island (36 N, W), Cádiz, Spain, May 1991, coll. J. E. Sánchez-Moyano; 3 males, body length 9.08 ± 0.56 ( ) clinging to the seaweed Dictyopteris membranacea on the intertidal zone of Tarifa Island (36 N, W), Cádiz, Spain, May 1991, coll. J. E. Sánchez-Moyano; 11 males, body length 8.12 ± 0.97 mm, range = mm, 3 females, body length 4.03 ± 0.21 ( ) clinging to algae on tidepools, 1 m in depth, Tarifa Island (36 N, W), Cádiz, Spain, June 1991, coll. J. E. Sánchez-Moyano. Diagnosis (based on male specimens). Body, with dorsal tubercles, densely overgrown by setae, especially developed on pereonites 2 3 and gnathopod 2. Palm of gnathopod 2 with deep semicircular excavation filled with membranous sac. Gnathopod 2 dactylus inner margin with 2 thickened

13 1026 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Fig. 10. Caprella takeuchii n. sp. a d, male. a, antenna 1; b, antenna 2; c, gnathopod 1; d, gnathopod 2. e, female gnathopod 2. Scale bars: A: 1 mm (a, b); B: 0.3 mm (c); C: 1 mm (d); D: 0.3 mm (e).

14 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1027 Fig. 11. Caprella takeuchii n. sp. a d, male. a, pereopod 5; b, pereopod 6; c, pereopod 7; d, abdomen. e, female abdomen. Scale bars A: 1 mm (a, b, c); B: 0.2 mm (d, e).

15 1028 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Fig. 12. Caprella takeuchii n. sp. Male. a, upper lip; b, lower lip; c, maxilliped; d, right mandible; e, left mandible; f, maxilla 1; g, maxilla 2. Scale bars: 0.2 mm. A: (a, b); B: (c, d, e, f, g).

16 GUERRA-GARCÍA ET AL.: TWO NEW SPECIES OF CAPRELLA FROM THE STRAIT OF GIBRALTAR 1029 humps. Gills elongate. Abdominal appendages 1-articulate. Lateral surface of lobes in upper lip and outer lobes in lower lip with dense setae. Description. Holotype male. Body length 8 mm. Head skull -like (see Krapp-Schickel and Vader, 1998), regularly convex, without rostrum or projections. Dorsal tubercles on pereonites 4 7 (following formula 2 1, 2, 2, 2). Body covered by setae, especially developed on pereonites 2 3 and gnathopod 2. Pereonite 1 fused with head, short. Pereonites 2 and 3 subequal. Pereonites 4 7 shorter, decreasing in length. Gills elongate, length about 3.5 times width. Antenna 1 about half body length; flagellum 11-articulate. Antenna 2 about half of antenna 1; swimming setae absent. Upper lip semicircular, symmetrically bilobed, pubescent apically and laterally on lobes. Outer lobes of the lower lip with setae laterally. Mandibular process strong. Incisor 5- toothed, lacinia mobilis 4-toothed. Row of 3 plumose setae on left mandible, 2 on right one. Molar flake on right molar. Maxilla 1 outer lobe with 7 forked, 2-pronged spines distally. Palp 2-articulate, distal article with 9 strong spines on end and row of 7 setae on ventral surface. Maxillae 2 as in C. monai n. sp. Inner plate of maxilliped bigger than outer one, with 3 teeth and plumose setae on apical margin. Outer plate bearing 1 tooth and simple setae distally. Palp 4-articulate. Gnathopod 1 similar to that of C. monai n. sp. Gnathopod 2 inserted at middle of pereonite 2, covered with setae densely, especially on dorsal surface of propodus. Basis about 1.5 times shorter than pereonite 2. Carpus short, length about half merus. Ischium and merus subequal. Propodus about 1.4 times longer than basis. Palm of propodus with deep semicircular excavation filled with membranous sac. Gnathopod 2 dactylus inner margin with 2 thickened humps. Pereopods 5 7 increasing in size respectively. Basis without carina. Palm of propodus bearing 2 medial grasping spines and several ones along hind-margin (see Krapp-Schickel and Vader, 1998). Pereopod 7 with some distal accessory spines. Penes situated laterally. Abdomen with pair of appendages, pair of lateral lobes, and single dorsal lobe. Abdominal appendages 1-articulate, not constrained medially, with short setae on end. Dorsal lobe with pair of plumose setae. Allotype female. Body length 3.97 mm. Dorsal tubercles on pereonites 4 7, following formula 1, 2, 2, 2. Pereonites 2 5 subequal. Flagellum of antenna 1 with 8 articles. Gnathopod 2 inserted on anterior half of pereonite 2. Palm of propodus straight, carrying 3 teeth on proximal end. Abdomen with pair of lateral lobes and single dorsal lobe, without appendages. Etymology. Caprella takeuchii n. sp. is dedicated to Dr Ichiro Takeuchi, for his contribution to the knowledge of the Caprellidea. Remarks. Caprella takeuchii n. sp. is very similar to C. acanthifera (Table 1). The most outstanding difference is the presence of setae covering the body in C. takeuchii. After consulting the literature, we can assert that C. takeuchii presents a character unique in the Caprellidea: the existence of setae situated laterally on the lobes of the upper lip and on the outer lobes of the lower lips. In other species the setae are only concentrated on apical ends of the lobes and never laterally as in C. takeuchii. On the other hand, although the presence of abundant setae on gnathopod 2 is a character relatively common in the genus Caprella, i.e., C. acanthogaster Mayer, C. californica Stimpson, C. ciliata Sars, C. fretensis Stebbing, C. grandimana Mayer, C. hirsuta Mayer, C. macho Platvoet, De Bruyne and Gmelig-Meyling, and C. tuberculata Bate and Westwood, only C. acanthogaster, C. macho, and C. tuberculata have setae also on the surface of pereonites, as in the two new species described here, C. takeuchii and C. monai. ACKNOWLEDGEMENTS We express our thanks to Compañia del Mar and Club Calypso from Ceuta for assistance in the field. Appreciation is also extended to Asamblea de Ceuta and a grant Programa de Formación de Profesorado Universitario v Personal Investigador AP98/ , from the Ministry of Education and Culture of Spain for financial support. LITERATURE CITED Bellan-Santini, D., and S. Ruffo Faunistics and Zoogeography. Pp in S. Ruffo, ed. The Amphipoda of the Mediterranean. Mémoires de l Institut Océanographique, Monaco 13. Carausu, S., and A. Carausu Contibution à l étude des Caprellidae (Crustacés Amphipodes aberrants) de la Mer Noire. I. Caprella acanthifera Leach (morphologie, écologie, variabilité). Lucrarile Sesiunii Stiintifice Agigea:

17 1030 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 21, NO. 4, 2001 Cavedini, P Contributo alla conoscenza dei Caprellidi del Mediterraneo. Bollettino del Museo Civico di Storia Naturale, Verona 8: Chevreux, E Sur quelques intéressantes espèces d Amphipodes provenant des parages de Monaco et des pêches pélagiques de la Princesse-Alice et de l Hirondelle II en Méditerranée. Bulletin de l Institut Océanographique, Monaco 262: Conradi, M., and P. J. López-González The benthic Gammaridea (Crustacea, Amphipoda) fauna of Algeciras Bay (Strait of Gibraltar): distributional ecology and some biogeographical considerations. Helgoland Marine Research 53: 2 8.,, and D. Bellan-Santini A new species of Urothoe (Amphipoda, Gammaridea) from the Iberian peninsula. Cahiers de Biologie Marine 36: 9 13.,, and J. C. García-Gómez The Amphipod Community as a bioindicator in Algeciras Bay (Southern Iberian Peninsula) based on a spatio-temporal distribution. P.S.Z.N.I: Marine Ecology 18: Guerra-García, J. M., and I. Takeuchi (In press.). The Caprellidea (Crustacea: Amphipoda) from Ceuta, North Africa, with the description of three species of Caprella, a key to the species of Caprella and biogeographical discussion. Journal of Natural History. Krapp-Schickel, T Suborder Caprellidea. Pp in S. Ruffo, ed. The Amphipoda of the Mediterranean. Mémoires de l Institut Océanographique, Monaco 13., and W. Vader What is, and what is not, Caprella acanthifera Leach, 1814 (Amphipoda, Caprellidea)? Part 1: The acanthifera-group. Journal of Natural History 32: Laubitz, D. R Caprellidae (Crustacea: Amphipoda): towards a new synthesis. Journal of Natural History 27: Mayer, P Die Caprelliden des Golfes von Neapel und der angrenzenden Meeres-Abschnitte. Fauna und Flora des Golfes von Neapel 6: Die Caprelliden des Golfes von Neapel und der angrenzenden Meeres-Abschnitte. Fauna und Flora des Golfes von Neapel 17: McCain, J. C., and J. E. Steinberg Amphipoda-I, Caprellidea-I. Crustaceorum Catalogus 2: Sánchez-Moyano, J. E., J. L. Carballo, and F. J. Estacio. 1995a. Pedoculina garciagomezi (Amphipoda: Caprellidea), new species from Bahía de Algeciras (Southern Spain). Crustaceana 68: , J. A. Jiménez-Martín, and J. C. García-Gómez. 1995b. Caprella santostosai n. sp. (Amphipoda: Caprellidea) from the Strait of Gibraltar (Southern Spain). Ophelia 43: RECEIVED: 13 July ACCEPTED: 16 April 2001.