Morphology of shallow-water sea spiders from the Colombian Caribbean

9 SPIXIANA 32 1 9–34 München, August 2009 ISSN 0341 – 8391 Morphology of shallow-water sea spiders from the Colombian Caribbean (Arthropoda: Pycnogonida) Maria Fernanda Montoya Bravo, Hans-Georg Müller, Claudia P. Arango, Paulo Tigreros & Roland R. Melzer Montoya Bravo, M. F., Müller, H.-G., Arango, C. P., Tigreros, P. & Melzer, R. R. (2009): Morphology of shallow-water sea spiders (Arthropoda: Pycnogonida) from the Colombian Caribbean. – Spixiana 32/1: 9-34 Scanning EM redescriptions of nine pycnogonid species belonging to the families Ammotheidae, Phoxichilidiidae, and Callipallenidae are provided and referenced to earlier light microscopical descriptions of the respective species. Specimens were collected at various locations and different infralittoral habitats around Santa Marta along the Caribbean coast of Colombia. Maria Montoya, Hans-Georg Müller and Roland Melzer (corresponding author), Zoologische Staatssammlung, Münchhausenstr. 21, 81247 München, Germany; e-mail: [email protected] Claudia Arango, Biodiversity Program, Queensland Museum, P.O. Box 3300, South Brisbane 4101 Queensland, Australia Paulo Tigreros, Universidad Jorge Tadeo Lozano, Carrera 2 #11-68 Santa Marta, Colombia. Introduction Most Pycnogonida or sea spiders of the tropical, coastal seas are very small (1-2 mm body length) and have cryptic habitats in the phytal zone or close to coelenterates, sponges and other benthic organisms (Arnaud & Bamber 1987). In the present paper we examine nine species of pycnogonids found at different infralittoral habitats in the area of Sta. Marta at the Caribbean coast of Colombia. The last comprehensive study on the pycnogonids of this area is by Müller (1990) with the description of 50 species, including seven new to science (see also Müller & Krapp (in press)). Since then only a few studies dealt with the Colombian pycnogonids, including reports about three species new for this area (Nymphon surinamense Stock, 1975, Anoplodactylus insignis Hoek, 1881, Pallen opsis schmitti Hedgpeth, 1943) by Arango (2000). The material for these studies was collected at Tayrona national park and around Cartagena. In the present study we contribute to the knowledge of some species of sea spiders from the Santa Marta region, mainly from unprotected coasts that are intensely used for fishing and tourism. For documentation we used the scanning electron microscope (SEM) that allows a direct and detailed analysis of the species-specific morphological characters, and we provide SEM (re)descriptions of the species. The present study aims to contribute to a pictorial atlas of Colombian pycnogonids. The classical studies on Caribbean pycnogonids that we refer to are by Marcus (1940), Hedgpeth (1948), Stock (1975, 1986) and Child (1979). For synonymy and detailed taxonomy see Müller (1990, 1993a), Müller & Krapp (in press). 10 Animals and Methods Sampling and fixation. The pycnogonids for the present study were collected at various locations between the airport bay of Santa Marta, west of the city, and the Cabo Arrecifes, about 30 km east of the city in the Tayrona national park. A detailed description of the sampling sites including the Bavarian State Collection’s storage number is given below for each of the studied specimens. In order to find pycnogonids from different habitats, samples were taken around corals and other coelenterates, from coral rubble, under stones and by whirling up sediment. Of these techniques, the under stone method, i.e. taking stones out of the water and checking the under stone benthic communities for pycnogonids proved to be the most successful way. The collected animals were fixed in 3 % formaldehydeborax in sea water and the next day transferred to 70 % ethanol. Cleaning of specimens. In order to get Scanning EM pictures of sufficient quality as well as for light microscopy most specimens had to be cleaned. For that, different methods were used: KOH solution in combination with an ultrasonic cleaner, some drops of dish-washing fluid in 70 % ethanol, 30 % H2O2 in 70 % ethanol (see Bolte 1996 for details), and a “Da Vinci” brush size N°00. Among these, the H2O2-method was most helpful and allowed to obtain rather clean specimens, even of the genus Achelia and Ammothella which are known to carry lots of epibionts and dirt on their cuticle. Microscopy. First, pycnogonids were analysed with a Leica DMRBE light microscope. For documentation a Spot-insight colour digital camera was used. In addition to conventional pictures, focus series were made and pictures with extended field of depth were generated on PC using the program Auto-Montage (Syncroscopy). Afterwards, specimens were dehydrated in a graded acetone series, critical-point-dried in a BAL-TEC CPD030, sputtered with gold in a Polaron “Sputter coater” and examined in a Leo 1430VP scanning EM at 17-30 kV. Scanning EM descriptions of the collected pycnogonids Ammotheidae Achelia Hodge, 1864 Achelia sawayai Marcus Achelia sawayi Marcus 1940: 81-86, Figs 10a-f, 17 Material. Adult M (ZSM-A-20071594); Casa Grisales, Bahia del Rodadero, Santa Marta; on stone with algae. 0.5-1.0 m. 11.10.2004; Juvenile (ZSMA-20071595); Playa Brava, Bahia de Taganga, Santa Marta; under stone, 0-0.5 m, 09.12.2004; Juvenile (ZSM-A-20060998); Playa Brava, Bahia de Taganga, Santa Marta; under stone, 0-0.5 m, 09.12.2004; Adult M (ZSM-A-20060999); Bahia del Rodadero, Santa Marta; under stone. 0.5-1.0 m. 14.12.2004; Adult W with eggs in the legs (ZSM-A-20071596); Bahia del Rodadero, Santa Marta; under stone, 0.5-1.0 m, 14.12.2004; Adult M carrying eggs on ovigera (ZSMA-20071597); Bahia del Rodadero, Santa Marta; under stone. 0.5-1.0 m. 18.12.2004. Description (Figs 1-4) Light microscopical descriptions of this species are given by Müller (1990), Müller & Krapp (in press), Hedgpeth (1948), Stock (1955), and Child (1992). Living animals are sand-coloured. No special pigmentation of the gut. Body circular (Figs 1D, 2C, 3A,B), segmentation lines not visible (Figs 1D, 2C, 3C-E), dorsodistal spination absent. Ocular tubercle relatively flat, deprived of apical protrusion; four strongly pigmented eyes and two lateral sense organs present (Figs 1D, 4A,E). Short abdomen orientated upwards (Figs 1D, 2C, 4A), inserted directly between walking legs 4 and having distally two laterodorsal short spines (Fig. 4A). Proboscis oval, with pointed tip (Fig. 4D). Chelifores composed of a long article and chelae that are well developed in juveniles (Figs 1B,G) but deformed in adults (Figs 2C, 4A,B). Palps with 8 articles in adults (Figs 2F, 4F) and 6 in juveniles (Fig. 1F). Ovigera with 10 articles in both sexes, articles 8-10 equipped with serrated spines (Fig. 4G-I). Male ovigera with spines on all articles. In specimen examined eggs were carried between 5th and 2nd ovigera article (Fig. 4G). Coxa 1 of all legs with 3 distal spines inserted on protrusions. In juveniles (Fig. 1E) these are less pronounced than in adults (Figs 3D, 4C). Coxa 2 equipped with 2 spines, 2× length of coxa 1; coxa 3 with bristles ventrodistally, same length as coxa 1. Length of femur 3× coxa 1. Adult male with strong protrusion (cement gland) at the dorsodistal edge of the article. Femur of ovigerous female swollen and filled with eggs (Fig. 2B). Tibia 1 0.2× as long as tibia 2. Both tibiae rather thin. Tarsus as long as wide, with several spines, ventrally with setae and distally with a single spine (Fig. 4K). Propodus slightly curved (Figs 1H, 2H, 3G, 4K), heel absent. Sole consists of a row of 6-9 thin short spines (Figs 3G, 4K), dorsomedially with 3-5 long thin spines (Figs 3G, 4K). Distal tip of propodus with curved main claw and two accessory claws at its dorsal side. Length of accessory claws 0.75× main claw (Figs 2H, 3G, 4K). 11 Fig. 1. Achelia sawayai Marcus, 1940, juvenile. A. Ventral view with walking legs (wal1-wal4), pedipalps (pp) and proboscis (pr). B. Chelifores (cf) with well developed chelae (ch) equipped with movable (fmov) and fixed fingers (ffix). C. Propodus (p) and tarsus (t) of 3rd walking leg with spines and sole (sl). Note accessory claws (ac) next to primary claw (pc). D. Dorsal view. Note lateral processes (lp) and humps (hu) with spines (sp) on coxa 1. E. Dorsal view of lateral processes and coxal articles (cx1-cx3). F. Lateral view of 6-jointed pedipalp (s1-s6) with setae on the 3 distal articles (st). G. Closeup of chelae. Note spines at their base and well-developed movable and fixed finger (fmov and ffix). H. Tarsus (t) and propodus (p), lateral view. Abd, abdomen; Ac, accessory claw; hu, hump; oc, ocular tubercle; pc, principal claw; sl, sole; sp, spine. A-C light microscopy, D-H SEM. Remarks. Achelia sawayai is a small species. Its colour can be explained as an adaptation to the habitat, i.e. infralittoral stones with algae. Due to variability of the spination and the presence of a very similar species, Achelia gracilis Verrill, 1900, the determination of A. sawayai is not trivial. However, the number of spines on coxae 1 of legs 1 and 2 (3 in A. sawayai and 4 in A. gracilis) turned out to be a good distinctive feature. This species is distributed along the Atlantic coast from Georgia (USA) to Brazil and Bahamas Is. In addition, in the Atlantic and Indian Ocean, samples have been reported from West Africa, Cape Verde Is. and Madagascar (Child 1979). In the Pacific, the species is known from Fiji (Müller 1990a), and French Polynesia (Müller 1989, 1990b). ABC 300 µm 50 µm 50 µm D100 µm E20 µm F20 µm G20 µm H20 µm 12 Fig. 2. Achelia sawayai Marcus, 1940, female. A. Dorsal survey; note thickened coxae (cx1-3) and femora (fm). B. detail of walking leg with eggs. C. Dorsal survey. D. coxa 2 with genital opening (go) and neighbouring seta (st). E. Detail of D. F. Dorsal view of proboscis (pr), 8-jointed palps (s1-s8), chelifores (cf) and ocular tubercles (oc). G. Lateral view of walking leg. H Propodus and tarsus. Abd, abdomen; ac, accessory claw; fm, femur; lp1-lp4, lateral processes; p, propodus; pc, primary claw; pp, pedipalp; pr, proboscis; sl, sole; sp, spine; t, tarsus; tb1, tb2, tibia 1 and 2. A, B, light microscopy, C-H, SEM. Ammothella Verrill, 1900 Ammothella exornata Stock Ammothella exornata Stock, 1975: 974-978, figs 7c-d. Material. Exuvy (ZSM-A-20061000), Bahia del Rodadero, Santa Marta; from substrate. 18.12.2004; Juvenile (ZSM-A-20061032); Playa Brava, Bahia de Bahia de Taganga, Santa Marta; from stone, 0-0.5 m, 27.12.2004; Juvenile (ZSM-A-20071598); Playa Brava, Bahia de Taganga, Santa Marta; from stone, 0-0.5 m, 27.12.2004; Adult M (ZSM-A-20071599); Playa Brava, Bahia de Taganga, Santa Marta; under stone, 0-0.5 m, 27.12.2004; Juvenile (ZSM-A-20061033); Playa Brava, Bahia de Taganga, Santa Marta; under stone, 0-0.5 m, 05.01.2005. A500 µm B100 µm C100 µm D E 20 µm F100 µm G100 µm H20 µm 10 µm 13 Fig. 3. Achelia sawayai Marcus, 1940, male, light microscopy. A, B. Surveys of whole animal, ventral view. C. Ventral view at higher magnification showing short abdomen (abd), flat ocular tubercle (oc), short reduced chelifores (cf) and funnel shaped proboscis (pr). D. Dorsal view of trunk; note absence of segmentation. E. Dorsal view of leg insertion showing spinulation (sp and arrowheads) of 1st coxae (cx1). F. survey of walking leg from coxa 2 (cx2) to tibia 2 (tb2). G. Propodus (p). Ac, accessory claw; Cx3, coxa 3; fm, femur; lp1, lp3, lateral processes 1 and 3; ov, ovigera; pc, primary claw; pp, pedipalp; sl, sole; t, tarsus; tb1, tibia 1; wal1-4, walking legs 1-4. Description (Figs 5-7) Living animals are sand-coloured with ganglia visible ventrally (Fig. 5B). Body slightly oval in shape (Fig. 5A), segmentation line between 3rd and 4th segment absent. (Fig. 6B), dorsally with numerous cone-shaped protuberances on all segments including the abdomen (Fig. 6C) that are less pronounced in juveniles (Fig. 5B,D). Slit organs or epidermal gland openings on the tip and at the sides of these (Fig. 5E, 6E-G). Ocular tubercle 2× as high as wide, with apical sense organ and two lateral sense organs. At the left and the right base of eye tubercle two protuberances, each with a distal gland pore (Figs 5D,I, 7I). Further pores on branched protuberances at the sides of eye tubercle (Fig. 7I). Small protuberance at the posterior base of tubercle (Figs 6B, 7I). Eyes strongly pigmented, anterior 2 about | deeper on the tubercle than the 2 posterior ones. Abdomen not separated from body, i.e. confluent A500 µm CDE 100 µm 100 µm 100 µm B500 µm F200 µm G 14 Fig. 4. Achelia savayai Marcus, 1940, male, SEM. A. Frontal view showing lateral sense organs (arrows) on ocular tubercle (oc), adjacent spines (arrow and sp) and those on the abdomen (arrowhead and sp). B. Closeup of chelifores (cf) with atrophied chelae (ach); arrowheads characteristic spines. C. Dorsal view of lateral processes (lp1-4) and 1st coxae (cx1); arrowheads spinulation. D. Tip of proboscis with mouth and haircoat (arrowheads) of the “lips”. E. Ocular tubercle with lateral sense organs (arrowheads). F. Distal pedipalp articles s4 to s8 with setae (st). G. 10-jointed (s2-s10) ovigera with eggs attached to it. H, I. Closeups of distal ovigera articles (s5-s10) with setae (arrowheads) and serrated spines (ssp). J. 3rd walking leg with process (pr) at the distal tip of the femur (fm). K. propodus with spines (sp) and sole (sl). Ac, accessory claw; cx2, coxa 2; cx3, coxa 3; p, propodus; pc, principal claw; t, tarsus; tb1, tibia 1; tb2, tibia 2. 100 µm 20 µm 20 µm 20 µm 20 µm 20 µm 20 µm 20 µm 100 µm 100 µm A B C DEF G I H JK 15 Fig. 5. Ammothella exornata Stock, 1975, juvenile. A. Survey viewed from dorsally. B. Ventral view of trunk and base of legs showing suture between segments (sb) and blunt proboscis (pr). C. tarsus (t) and propodus (p) with spinulation and sole (arrowheads, sp, sl). D. Dorsolateral view of dorsal trunk protrusions (prt). E. Protrusions on lateral processes (lp) and coxa 1 (cx1) (prt, arrowheads) with slit-shaped gland opening on top (so). F. Chelifore (arrowheads and sp: spinulation). G. Propodus of walking leg no. 3 (arrowheads and sp: spinulation). H. Closeup of 5 jointed palps (s1-s5). I. Ocular tubercle (oc) with lateral processes (pr), eye cuticle (e) and lateral sense organ (lso). J. Dorsal view of abdomen. Abd, abdomen; ac, accessory claw; an, anus; ch, chelifore; ffix, fixed finger of chelae; fmov, movable finger of chelae; g, ganglion; m, mouth; p, propodus; pc, primary claw; pp, pedipalp; pr, proboscis; prt, protrusion; sl, sole; t, tarsus; wal, walking leg. 300 µm 100 µm 50 µm 100 µm 20 µm 20 µm 20 µm 20 µm 20 µm 20 µm ABC DE FG HI J 16 Fig. 6. Ammothella exornata Stock, 1975, male. A. Dorsal survey. B. Trunk and base of walking legs with spines (arrowheads) and large protrusions on the midline (prt); note segmentation lines. C. Anterolateral view; arrowheads spines on midline of body and abdomen. D. Detail showing hairy spine (hsp). E. Detail showing some of the dorsal protrusions (prt), each with several slit organs (so). F, G. Slit-shaped gland pores with neighbouring branched hair (bh). Abd, abdomen; cf, chelifores; hu, hump; m, mouth; oc, ocular tubercle; pp, pedipalps; pr, proboscis; sb, segment border; wal1-4, walking legs. A200 µm 100 µm 100 µm 20 µm 2 µm 2 µm20 µm B CD F GE 17 Fig. 7. Ammothella exornata Stock, 1975, male. A. Chelifores with rudimentary chelae (ach) and hairy spines (hsp). B. Palps. C. 1st coxa (cx1) with spination (arrowheads) and “slit”-shaped gland pores (so). D. Survey of walking leg with sexual organ on coxa 2 (cx2) including spur (sp). E. Femur (fm) with distal seta (st) and several hairy spines (hsp). F. Propodus (p) of 3rd walking leg with well visible accessory claws (ac); Hsp and arrowheads hairy spines. G. 10-jointed ovigera. H. Distalmost ovigera articles (s7-s10) with spine and feathered hairs (arrowheads). I. Ocular tubercle (oc) with eyes (e) and lateral sense organs (lso). In the neighbourhood, hairy spines (hsp) and protrusions with slit organs (prt and so) are seen. J. Survey of abdomen with anus (an), spinulation (sp) and protrusions (prt and aprt). Bprt, branched protuberance; Cx3, coxa 3; fm, femur; Jm, joint membrane; p, propodus; pc, principal claw; s1-s10, articles of body appendages; sl, sole; sp, spine; t, tarsus; tb1, tibia 1; tb2, tibia 2. 20 µm 100 µm 20 µm 100 µm 20 µm 20 µm 100 µm 20 µm 20 µm 20 µm ABC DEF GH IJ 24 Fig. 12. Ammothella sp., juvenile. A. Survey of whole animal. B. Dorsal view of trunk (b). Note presence of well developed chelae (ch) on chelifores (cf) and long ocular tubercle (oc). C. Dorsal aspect of trunk with well visible segment borders (sb). On the surface of the body larger spines or protrusions are absent; arrowheads: branched hairs. D. Dorsal view of coxa 1-3 (cx1-3). E-H. Series of fotos showing the structure of walking leg 3 from coxa 3 to propodus (p); arrowheads and sp indicate position of spines and hairs; note long hair at the tip of femur (asterisk). I. Detail of propodus with appendages; arrowheads and sp indicate spinulation of sole. Abd, abdomen; ac, accessory claw; bh, branched hair; ch, chelifore; cx1, coxa 1; fm, femur; jm, joint membrane; lp, lateral process; p, propodus; pc, principal claw; pp, pedipalp; pr, proboscis; sl, sole; sp, spine; t, tarsus; tb1, tibia 1; wal1-wal4, walking legs. bristles are inserted medially, and 1 thin spine at the base (Fig. 13I). Lamella located distally at } of the propodus’ length. 2 small bristles each inserted at its base and tip (Fig. 13F). Main claw 0.6× as long as propodus. 2 very small accessory claws at the base (Fig. 13F). Absence of ovigera and segmentation indicates juvenile stage of the studied pycnogonid. Remarks. Anoplodactylus micros is a rather small, thin species. The studied individual was found near the shore under a stone, close to Millepora corals. The shape of the propodus and of the spine at its base are distinctive features of A. micros. We note absence of a segmentation line between segments 2 and 3 compared to the 2 individuals described in Müller (1990) and Müller & Krapp (in press) that have this border. To date, reports of A. micros are restricted to the Caribbean (Müller 1990). Anoplodactylus monotrema Stock Anoplodactylus monotrema Stock, 1979: 15-18, figs 4-5 Material. Adult W (ZSM-A-20071605); Casa Grisales, Bahia del Rodadero, Santa Marta; from stone with algae, 0.5 m, 10.12.2004; Juvenile M (ZSM-A-20071606); Playa Brava, Bahia de Taganga, Santa Marta; under stone, 0.5 m, 09.12.2004. Description (Figs 14, 15) Living animal coloured yellowish to orange. Ganglia and gut well visible (Fig. 14B). Body oval, wide and robust (Figs 14A, 15A). Segmentation reduced (Fig. 15A). A small hair inserted distally on each segment. Walking legs also robust (Fig. 15A,G). Eye tubercle flat, only slightly higher than wide (Figs 14B,C, 15D). Eyes strongly pigmented (Fig. 14C). Apical sense organ at the tip and 2 lateral sense organs present (Fig. 15D). Proboscis short and frontally flattened (Fig. 14D). Abdomen of almost same height as eye tubercle; several hairs close to anus (Fig. 15A,E). Chelifores 2-jointed, article 1 larger (Fig. 15B). Chelae relatively strong, located directly on top of mouth. Several small, pointed teeth at inner sides of the fingers (Fig. 15C), several hairs distributed all over them. Ovigera with 2 to 3 articles; borders between them not well visible (Fig. 14D). Coxa 1 with distal groove and 2 laterodistal hairs. Coxa 2 and 3 of same length, deprived of grooves and hairs. Femur 2× as long as coxa 3; distal protrusion with spine at tip. Tibia 1 similar to femur, distal protrusion with spine also present. Tibia 2 thinner than tibia 1. At ‚ of its length, a protuberance with spine is seen (Fig. 15G). Tarsus 2× as wide as high, with lots of hairs (Fig. 15F,H). Propodus robust, slightly curved (Figs 14E, 15F,H). Heel with 2 strong spines and 2 setae neighbouring them (Fig. 15I). Sole with medial row of small spade-shaped spines (Fig. 15F) and 2 lateral rows of hairs with rounded tips (Fig. 14E). Main claw 0.75× as long as propodus. Accessory claws very short and rudimentary (Fig. 15F,H). Remarks. Our Colombian individuals of Anoplodactylus monotrema are well characterized by propodus characters and the absence of coxal spines. The heel spines described here are missing in earlier descriptions. Most remarkable are the spade-shaped spines of the sole that are of different form than those of the heel. Ovigera composed of 5 articles found in males of this species seem to be fully developed late in ontogeny, as our subadult male had only 2 to 3 articles that were hard to distinguish. This species has often been mixed with Anoplodactylus robustus (Dohrn 1881). A good differential character, however, is the toothed finger of the chelae. A. monotrema is distributed in the Western Atlantic Ocean from Florida to Brazil, and the first record for Colombia is that of Müller (1990). Anoplodactylus pectinus Hedgpeth Anoplodactylus pectinus Hedgpeth, 1948: 234-236, fig. 34. Material. Adult W (ZSM-A-20071607); Piedra del ahogado in Playa Cristal (Playa del muerto), Nenguangue, Nationalpark Tayrona, Santa Marta; from stone in coral rubble, 20 m, 13.10.2004. / 25 200 µm 200 µm 20 µm 100 µm 100 µm 100 µm 100 µm 100 µm 10 µm AB CD EFG HI 26 Fig. 13. Anoplodactylus micros Bourdillon, 1955, male. A. Dorsal survey of whole animal. B. Lateral view of trunk and proximal leg sections; note pronounced segment border between segment 1 and 2 (sb). C. Lateral view of ocular tubercle (oc) and chelifores (cf) with chelae (ch). D. chela with dentated (arrowheads) fingers and spines (sp). E. Lateral protrusion and coxa 1 (cx1) of second walking leg (lp2); note small median spine (arrowheads). F. Tarsus (t) and propodus (p) of walking leg no. 3 showing specific spinulation (arrowheads, sp). G. Coxa 1 and lateral processes (lp3, lp4) of 3rd and 4th legs. H. Lateral view of distal tip of tibia 1 (tb1) with spines (sp). I. Detail of lamella (lm) in the propodus’ sole area; arrowheads: spines. J. Ocular tubercle (oc) with eye (e) and lateral (lso) and apical (ao) sense organs. K. Abdomen with anus (an) and 2 small spines at the base of the anus flaps (arrowheads). Abd, abdomen; cf, chelifore; cx1-cx3, coxa 1-3; h, heel; oc, ocular tubercle; pc, primary claw; pr, proboscis; prt, protrusion; sb, segment border; sl, sole; wal1-wal4, walking legs 1-4. Description (Fig. 16) Living animal sand-coloured. Body slender (Fig. 16A,B). Trunk segments 1-3 separated by well visible borders (Fig. 16B). Segments 3 and 4 fused. Lateral projections of thorax smooth, deprived of additional structures (Fig. 16B). Legs thin, become thinner distally (Fig. 16A,F). Eye tubercle of cylindrical shape, distally flattened. Two lateral sense organs on its distolateral sides. Apical sense organ absent (Fig. 16E). Eye pigmentation the strongest in the upper eye parts. Abdomen 3× as long as eye tubercle, directed upwards. 2 spines close to anus. Chelifores with 2 articles (Fig. 16C,D). 1st of these 2× as long as chelae. Both fingers of chelae slender, strongly curved, and equipped with small pointed teeth on inner sides (Fig. 16D). Some spines on outer sides of fingers. Palps absent as is characteristic of this genus. Ovigera only in males, made of 6 articles. Lateral projections very slender, of the same length as coxa 1 (Fig. 16B). The latter only slightly longer than wide. Coxa 2 1.5× as long as coxa 1 (Fig. 16F). Ventrodistally with median genital porus in the form of a small thickening. Coxa 3 of same length as coxa 1. Femur 4× as long as coxa 3. Femur more robust than other leg articles, with distal protrusion equipped with long slender spine (Fig. 16F). Tibiae of equal length. As with femur, a distal thin spine is inserted on tibia 1. Similar spine at } of the length of tibia 2. Tarsus as long as wide, with several ventral bristles and small spine (Fig. 16G). Propodus 4× as long as wide. Heel with 2 spines (Fig. 16G,H). Anterior spine comb-shaped and stronger than posterior spine (Fig. 16H,I)). Sole made of numerous small, slightly curved spines (Fig. 16H). Main claw not very robust, deprived of accessory claws (Fig. 16G). Remarks. Anoplodactylus pectinus is a slender species that can be unequivocally determined using the comb-shaped spine on the heel (Child 1979). It seems closely related to the A. tenuicorpus-complex (Arango & Krapp 2007, Bartolino & Krapp 2007) from the Indo-Pacific. The species in this complex are much more slender and delicate than A. pectinus, do not have a heel and are also characterized by the multiple cup or pore shaped cement glands; A. pectinus has a single cribriform cement gland. A. pectinus is distributed in the Atlantic Ocean from Mexiko to Panama (Child 1979) and from Madagascar and Batan Island in the Pacific (Child 1988). The first record from Colombia is that of Müller (1990 & in press), who found it at depths between 1 and 5 m, while the specimen studied here are from 20 m. Anoplodactylus sp. Material. Subadult W (ZSM-A-20061034); Casa Grisales, Bahia del Rodadero, Santa Marta; from stone with algae; 0-0.5 m; 11.10.2004. Description (Fig. 17) Living animal of dark green colour. Body of oval shape (Fig. 17A,B). Legs robust, 3.5× as long as trunk. Proboscis short, with blunt tip (Fig. 17B). Body segments with well developed margins. (Fig. 17B). Eye tubercle flat, with 4 dark-pigmented eyes. Abdomen short. Chelifores of same length as proboscis, chelae in front of mouth (Fig. 17A). 2 small teeth on inner finger (Fig. 17F). Palps absent as well as ovigera in female specimen. Coxa 1 with 2 to 3 small setae located distally, and a mediodistal small groove (Fig. 17A,B). Coxa 2 almost 2× as long as coxa 1, also with small distal bristles. Coxa 3 of same length as coxa 1 (Fig. 17A,B). Femur slightly swollen, no eggs visible (Fig. 17C). Femur 2× as long as coxa 2. Thin distal spine present (Fig. 17C). Tibia 1 slightly wider and longer than tibia 2. Both tibiae with short distal spine (Fig. 17C). Tarsus longer than wide; at its dorsal side a short seta is inserted. Ventral side with several setae (Fig. 17D,E). Heel with 1 spine on 1st leg, 2 spines on 2nd and 4th leg, and 3 spines on 3rd leg (Fig. 17D,E). Two setae of equal length at the heel’s bases. Sole made of a median row of thick spines and 2 lateral rows of shorter and thinner setae (Fig. 17D,E). Main claw 0.75× as long as propodus (Fig. 17D). / 27 200 µm 100 µm 100 µm 10 µm 20 µm 20 µm 20 µm 20 µm 20 µm 10 µm 20 µm AB A CDE F G H IJK 28 Fig. 14. Anoplodactylus monotrema Stock, 1979, juvenile (male), light microscopy. Dorsal view of whole animal. B. Dorsal view of trunk and leg base; note pigmented gut (gt) and short abdomen (abd). C. Anterior part of body with slender chelifores (cf) and chelae (ch); well pigmented eyes are seen in the ocular tubercle (oc). D. Ventral view of short proboscis (pr) and ovigera (ov). E. tarsus (t) and propodus (p) of 3rd leg showing spinulation (arrowheads); the heel is equipped with two spines (sp) and seta (st), sole made of three rows of spines (sp) and hairs (hr). lp1-lp3, lateral protrusions of legs 1-3; pc, primary claw; pr, proboscis; wal1-wal4, walking legs 1-4. 300 µm 50 µm 50 µm 50 µm 50 µm AB CD E 29 Fig. 15. Anoplodactylus monotrema Stock, 1979, female. A. Dorsolateral view of whole animal. B. 1-jointed chelifore (s1) and chela (ch). C. detail showing teeth (th) on both the movable (fmov) and fixed (ffix) finger; arrowheads: hairs. D. Ocular tubercle with eyes (e), lateral (lso) and apical (ao) sense organs. E. Abdomen with anus (an) and surrounding hairs (arrowheads). F. 3rd propodus, viewed from ventrally, with primary (pc) and short accessory claw (ac); on tarsus (t) as well as on propodus (p) numerous spines and hairs are seen (arrowheads). Among these, note strong spines (sp) and setae (st) on heel. The median row of the sole is composed of spade shaped spines (spl). G. Walking leg 3 with hairs (arrowheads), and protrusion on femur (prt). H. Lateral view of propodus showing arrangement of hairs on the outer edge (arrowheads). I. Detail of heel (h) with spines (sp), hairs (hr) and setae (st). abd, abdomen; ac, accessory claw; cx3, coxa 3; fm, femur; h, heel; hr, hairs; l, lips of proboscis; m, mouth; oc, ocular tubercle; pc, primary claw; pr, proboscis; tb1,2, tibia 1 and 2; wal1-wal4 walking legs 1-4. 200 µm 20 µm 20 µm 20 µm 20 µm 20 µm 200 µm 100 µm 10 µm A C B DE F GHI 30 Fig. 16. Anoplodactylus pectinus Hedgpeth, 1948, female. A. Survey, dorsal view. B. Trunk and base of legs; note segment borders (sb). C. Chelifores made of one basal article (s1) and chelae (ch). D. Detail showing teeth of movable and fixed finger (fmov and ffix) and arrangement of hairs (arrowheads). E. Ocular tubercle with eyes (e) and lateral sense organ (lso). F. Survey of walking leg showing articulation and spinulation (arrowheads). G. Survey of propodus (p) and tarsus (t) with dorsal hairs (arrowheads), and spines (sp) and setae (st) at the ventral side; note large serrated spine (ssp) at the base of propodus. H. Sole of propodus with its spines (sp) and adjacent protrusions. I. detail showing the serrated spine (ssp). Abd, abdomen; cx1-3, coxa 1-3; fm, femur; lp, lateral processes; oc, ocular tubercle; p, propodus; pc, primary claw; pr, proboscis; sl, sole; tb1,2, tibia 1 and 2; wal1-wal3, walking legs 1-3. 1 mm 200 µm 100 µm 20 µm 20 µm 1 mm 100 µm 20 µm 20 µm AB CDE FG HI 31 Fig. 17. Anoplodactylus sp., female. A. Dorsal view of trunk and base of legs; arrowheads and asterisks spinulation of 1st coxae (cx1); note relatively short abdomen (abd) and flat ocular tubercle (oc). B. Ventral view with ganglia (g), and blunt proboscis. C. Survey of leg from femur (fm) to propodus (p); arrowheads: spines. D, E. Closeups of 1st and 3rd propodus; spinulation of dorsal side and tarsus indicated by arrowheads; heels have varying numbers of appendages: the 1st leg has one spine (sp) and a pair of setae (st), the 3rd three spines and a pair of setae. F. Chelae (ch) with chelifore article (s1), fixed (ffix) and movable (fmov) fingers; note small tooth (th) on fixed finger and characteristic distribution of setae (arrowheads). Ac, accessory claw; cf, chelifore; cx1,2, coxa 1, 2; Lp, lateral process; pc, primary claw; pr, proboscis; sl, sole; t, tarsus; tb1,2, tibia 1 and 2. 250 µm 250 µm 50 µm 100 µm 100 µm 50 µm AB C DEF 32 Fig. 18. Callipallene brevirostris (Johnston, 1837), female. A. Survey of whole animal. B. Dorsal view of trunk and lag bases; arrowheads indicate segment lines. C. Anterior view of chelifores composed of one basal article (s1) and the chelae (ch); spinulation indicated by arrows. D. Detail of mouth with lids (l), hairs (hr) and adjacent setae (arrowheads). E. Survey of ovigera from article 3 to 10 (s3-s10); arrowheads: hairs; note protrusion on s5. F. Closeup of serrated spines (ssp, arrowheads) on s9 and s10. G. walking leg 3; some of the characteristic hairs are indicated by arrowheads. H. propodus with 4 basal spines (sp) and characteristic arrangement of hairs (arrowheads); circle, rough area at the base of the accessory claws (ac). Cf, chelifore; ch, chelae; cx1-3, coxa 1-3; fm, femur; lp, lateral process; n, neck; oc, ocular tubercle; ov, ovigera; p, propodus; pc, primary claw; pr, proboscis; sp, spine; t, tarsus; tb1,2, tibia 1 and 2; wal1-wal3, walking leg 1-3. Remarks. It was not possible to determine this pycnogonid since it differs strongly from A. monotrema due to the segmentation, the varying number of heel spines and the 2 setae at the heel’s base. On the other hand, the studied individual also differs from A. robustus and A. virecens, the two other Caribbean species our subadult W might belong to: Due to its segmentation our specimen strongly differs from A. robustus, and due to the toothed fingers of the chelae it differs from A. virescens. In addition, the bristles and the groove on coxa 1 are not mentioned in earlier descriptions. Another very similar species is A. brevirostris from the Philippines. However, the latter species differs from ours in having one further spine on the heel of leg 4. Hence, our specimen might belong to a previously unknown species closely related to A. monotrema. Since we found only a subadult, single individual, further samples and studies will be necessary to assign this individual to a species. Callipallenidae Callipallene Flynn, 1929 Callipallene brevirostris (Johnston) Pallene brevirostris Johnston, 1837: 380, pl. 12, figs 7-8. Callipallene brevirostris: Flynn, 1929: 252. Change of combination. Material. Adult M (ZSM-A-20071607); Bahia Concha, Parque Nacional Tayrona, Santa Marta; from Sargassum cymosum, close to coelenterate colonies, on a stone with various algae on top, 20 m, 26.10.2004. Description (Fig. 18) Living animal of light red colour. Body robust, slender (Fig. 18A). Segmentation of body well visible (Fig. 18A,B). Laterodistal parts of trunk deprived of spines (Fig. 18B). Legs separated from each other { of their diameter, very long and slender (Fig. 18B). Eye tubercle small, flat, equipped with 2 lateral sense organs (Fig. 18B). Abdomen short, on both sides armed with a spine (Fig. 18B). Chelifore with 2 articles, together with the cylindrical proboscis separated from trunk by a short neck. Posterior setae on 1st article. Chelae dorsally curved, fingers distally with several setae (Fig. 18C), a row of several roundish, blunt teeth on inner side. Chelae located directly in front of mouth. The latter made of 3 lips with numerous hairs (Fig. 18D). Palps absent in this genus. Ovigera with 10 articles, and medium number of bristles (Fig. 18E,F). 5th article with distal protrusion and a thin spine on top. This article is the longest, followed by the 4th. Other ovigera articles of same length. Distalmost 4 articles each with 5-7 serrated spines on ventral sides (Fig. 18E,F). On the figure only 2 of them are visible. Coxa 1 of all legs with some thin setae distally (Fig. 18B,G). Coxa 2, 2.5× as long as coxa 1; also with some setae distally. Coxa 3, 0.6× as long as coxa 1, also with distal setae (Fig. 18G). Femur slightly wider than following leg articles, but of approx. same length. Tibia 2 slightly longer. All leg articles with several small setae dorsally and dorsodistally (Fig. 18G). Tarsus as long as wide, with ventral spine and several small setae (Fig. 18H). Propodus curved, 4 long alternating spines on the proximal part (Fig. 18H). Sole with median row of strong small spines and 2 lateral setae of medium length. Further setae on the dorsal and lateral parts of the propodus (Fig. 18H). Main claw 0.3× as long as propodus. Accessory claws 0.75× as long as main claws. Auxiliaries with tiny denticles at base (circle in Fig. 18H). Remarks. Callipallene brevirostris is a rather large pycnogonid. Our specimen was the only pycnogonid we found directly on algae, where it sat well hidden due to its colour. The flat eye tubercle and the segmentation of the last segment are distinctive features with respect to Callipallene longicoxa, a very similar species. Müller (1990), Müller & Krapp (in press) report this species close to the shore, while our specimen is from a SCUBA sample from a depth of 20 m. C. brevirostris is common in the Mediterranean and Northern Atlantic (Stock 1987), previously reported from Colombian coasts in Müller (1990 & in press). / 33 200 µm 100 µm 100 µm 10 µm 100 µm 20 µm 200 µm 20 µm AB CD EF GH