Bijdragen lot de Dierkunde, 62 (1) 21-36 (1992) SPB Academie Publishing bv, The Hague Marine interstitial Amphipoda and Isopoda (Crustacea) from Santiago, Cape Verde Islands Jan H. Stock & Ronald Vonk Institute of Taxonomie Zoology, University of Amsterdam, P.O. Box 4766, 1009AT Amsterdam, The Netherlands Keywords: Amphipoda, Isopoda, interstitial, Cape Verde Islands Abstract Material and methods Three of recorded from interstices of The material which this is based been species Amphipoda are a on paper has collected with marine beach the island of Verde Bou-Rouch tidal on Santiago, Cape Archipela- a biophreatical pump (see Bou, 1975), on a littoralis Psam- beach flat the island of in the Verde Ar- go: Cabogidiella n. gen., n. sp. (Bogidiellidae), on Santiago Cape 50 mogammarus spinosus n. sp. (Melitidae), and Idunella sketi chipelago,at a depth of some cm below the substrate surface, Karaman, 1980 (Liljeborgiidae).The latter, widely distributed at several places between low-tide and a zone rather high in the species (West Indies, Canary Islands), is new to the Cape Verde mediolittoral belt. The sediments in which the animals lived con- Islands. Furthermore, an isopod is described from the same lo- sisted of a mixture of gravel, coarse sand, and some silt. At the Caecostenetroides mixtum of the the in the cality, n. sp. (Gnathostenetroididae). moment sampling, salinity was same as open sea, but - because the beach in question is situated in the mouth of a temporarily dry torrent which carries water only during ex- Résumé ceptional showers - an occasional decrease in salinity is possible. Trois espèces d’Amphipodes sont signalées d’interstices d’une plage marine sur l’île de Santiago, archipel du Cap-Vert: Cabogidiella littoralis et nov. (Bogidiellidae), Psam- gen. sp. Taxonomic part mogammarus spinosus sp. nov. (Melitidae) et Idunella sketi 1980 Karaman, (Liljeborgiidae).La dernière, une espèce large- AMPHIPODA ment répandue (Indes occidentales, îles Canaries), est nouvelle les îles du décrit de la même pour Cap-Vert. Également localité, Family Bogidiellidae un Caecostenetroides mixtum est Isopode, sp. nov. (Gnatho- stenetroididae). Cabogidiella n. gen. Introduction Diagnosis. - Bogidiellidae with 5 pairs of coxal gills (on pereionites 2 through 6). Molar part of the frame of In of a study on the stygofauna the mandible in reduction. Palp of first maxilla mid-Atlanticislands, a visit was paid to two islands 2-segmented. Pleopodal exopodites 3-segmented, of the Verde The Uro- Cape Archipelago. present paper not sexually dimorphic; endopodite absent. describes number a of malacostracan crustaceans pod 1: both rami of both sexes modified into found in interstitialwaters of a marine beach on the dagger-like structures. Rami of uropod 3 subequal island of Santiago. Previous to our studies, no in length. stygofaunal crustaceans were known from this The genus is monotypic; type-species C. littoralis island. n. sp. 22 J.H. Stock & R. Vonk - Marine interstitial Crustacea from the Cape Verde Islands Derivatio nominis. - The generic name is a con- Genera nrs. 7 and 8 differ from Cabogidiella in traction of the terra typica, the Cape Verde Islands, an apomorphic, 1-segmented palp of maxilla 1 (ver- and the of the of the and in name type-genus family sus 2-segmented), "special" pleopods (third The inter- Bogidiellidae. specific name refers to the exopodite segment minute or absent; endopodite at tidal habitat. least as long as first exopodite segment). No doubt, the new genus Cabogidiella is closest Remarks. - Withinthe family Bogidiellidae (sensu to Antillogidiella (nr. 5) and Actogidiella (nr. 6), Stock, 1981, and Coineau & Stock, 1986), there are both endemic to the West Indian area sensu lato. that the transformation several (sub)genera share The latter two differ (1) in having coxal gills on of of 1 into less one or both rami uropod more or pereionites 4 through 6 only (on 2 through 6 in the dagger-shaped structures: (1) Pseudingolfiella new genus); (2) in lacking a dagger-like modifica- Noodt, 1965; (2) Dussartiella Ruffo, 1979; (3) Ker- tion in the rami of uropod 1 of the male (although guelenella Ruffo, 1974; (4) Bollegidia Ruffo, 1974; those of the female are modified as in both sexes of (5) Antillogidiella Stock, 1981; (6) Actogidiella Cabogidiella); and (3) in showing sexual dimor- Stock, 1981; (7) Marigidiella Stock, 1981; (8) phism in pleopod 2 (none in the new genus). Marinogidiella Karaman, 1982*; (9) Cabogidiella As is usual in the Bogidiellidae, the (sub)genera n. gen.; and perhaps (10) Aurobogidiella Karaman, are characterized by a combination of apomorphic 1988. Most of share of and characters of rather refined these genera the same type plesiomorphic a habitat, viz. marine intertidalor sublittoral sands. nature. In Cabogidiella, the absence of sexual Dussartiella from freshwater Only comes a spring dimorphism in the pleopods and the high number and Antillogidiella has been found in a brackish of coxal gills (5 pairs) are plesiomorphic, but the well and in an anchihaline cave. modified uropod 1 in both maleand female and the Of these reduced molar of mandible genera, nr. 1 is characterized by an apo- part the are apo- morphic (uniramous) uropod 3. Nr. 2 has an apo- morphic. morphic (reduced) mandible palp, a parviramous and uropod 3, a plesiomorphic (multisegmented) in the littoralis exopodite pleopods. Nr. 3 is, amongst other Cabogidiella n. sp. characters, characterized by apomorphic (uniseg- (Figs. 1-2) rami of the Nr. 4 mented) pleopods. possesses an The - apomorphic (uniramous) uropod 1. remaining Material. All from the intertidal zone of a beach in the mouth of a dry riverbed, genera, nrs. 5 through 10, belong to the cluster S.W. ofAchada de Santo Antonio (island of 2 Santiago, S.W. of Praia); UTM coordinates TS 2785 x around the genus Bogidiella. l6 4885; 31 Jan. 1991. Of these, nr. 10 possesses, according to Kara- Sta. 91-24: 1 1 89 in o* (holotype), Ç (allotype), paratypes, man's (1988) Fig. 1J, a dagger-shaped endopodite a bank of fine gravel at mid-tide (Zoölogisch Museum Amster- in uropod 1, but in his text (: 101) this shape is dis- dam, ZMA Coll. Nr. Amph. 108.832). 1 missed as due to previous damage. The exopodite Sta. 91-21: paratype, in a tidal pool filled with sand and mid-tide of gravel, at (ZMA Amph. 108.835). uropod 1 in this genus is more or less plesio- 11 Sta. 91-22: paratypes, in a creek with sandy bottom, below morphic, in that it bears some distal spines. the mid-tide level (ZMA Amph. 108.833). Aurobogidiella differs moreover from Cabogidiella Sta. 91-23: 12 paratypes, near the low-tide line, in rather fine in the plesiomorphic 4-segmented exopodites of sand (ZMA Amph. 108.834). pleopods 1 and 2 (versus 3-segmented), the absence Accompanying interstitial fauna: Caecostenetroides mixtum of n. sp. (Isopoda), Psammogammarusspinosus n. sp., Dulzura a coxal gill on pereionite 2 (versus presence), and lobata Stock & Vonk, 1991, Idunella sketi Karaman, 1980 (Am- a less reduced mandible (with spine row between in- phipoda), and Staurocladia sp. (Hydrozoa). cisor and molar). Description. - Small-sized species (body length * As the date of to of publication Karaman's see Coineau paper, 1.13-1.49mm, n = 10); males tend to be slightly & Stock, 1986: 580. smaller than females. Body shape as typical of the Bijdragen tot de Dierkunde, 62 (1) - 1992 23 Fig. 1. Cabogidiellalittoralis n. gen., n. sp., paratypes: a, antenna 1, (scale A); b, antenna 2, (A); c, right mandible, (D); d, left corpus mandibulae, (D); e, labium, (E); f, maxilla 1, (D); g, maxilla 2, (D); h, maxilliped, (D); i, tip of maxillipedal from different of palp, , seen a angle (B); j, gnathopod 1, (C); k, gnathopod2, (C); 1, coxal gill and oostegite pereiopod 5, (C). Scales on Fig. 2. 24 J.H. Stock & R. Vonk - Marine interstitial Crustacea from the Cape Verde Islands Basis with Bogidiella-group; blind, colourless. 1 long seta on posterior margin. Propo- with 2 of size that Antenna 1 (Fig. la) spines on ventral mar- dus same as of gnathopod 1, elongate- of 2 with gin of peduncle segment 1 ; segment 2 about 75% ovate; palmar angle spines; palmar margin length of segment 1 ; segment 3 more than 50% of setae only. length of segment 2. Accessory flagellum Pereiopods 3 (Fig. 2a) and 4 of similar morpholo- armed. 5 2-segmented, long. Flagellum 7-segmented; long gy, very poorly Pereiopod (Fig. 2b) slight- than aesthetascs on segments 3 through 6. ly longer pereiopod 4, poorly armed. Pereio- Antenna 2 (Fig. lb) with short, plump gland pod 6 as long as pereiopod 5 and of similar mor- cone. Flagellum 5-segmented; 1 short aesthetasc on phology. Pereiopod 7 (Fig. 2c) longer and more segment 5. robust than pereiopod 6 and more strongly armed, with distal end of and Mandibles (Figs, le, d): Incisor short, robust, some long setae on carpus anterior of teeth poorly developed. Right lacinia mobilis finely some very long setae on margin propo- dus. Claw about 60% of of denticulate; left lacinia vaguely 5- or 6-dentate. very long, length propo- Molar reduced in size; left molar with minute seta, dus. No lentiform organs on pereiopods 3 to 7. right molar without seta. Palp 3-segmented; seg- Coxal gills on pereionites 2 through 6, ovate with ment 2 distally swollen, with 1 seta; segment 3 nar- poorly demarcated basal stalk; very small (not ex- than 3 ventral of coxal rower segment 2, with (sub)distal setae. tending beyond margin plate) on Labium (Fig. le) with well-developed outer pereionite 2, small (but extending beyond coxal inner lobes almost lobes; probably represented by plate) on remaining pereionites (Fig. II). Oostegites stretch between lobes. in distal straight outer on pereionites 2 through 5, short, linear, Maxilla 1 (Fig.