Ascorhynchus castellioides Stock, 1957

Müller, Hans-Georg & Krapp, Franz, 2009, The pycnogonid fauna (Pycnogonida, Arthropoda) of the Tayrona National Park and adjoining areas on the Caribbean coast of Colombia 2319, Zootaxa 2319 (1), pp. 1-138 : 57-58

Ascorhynchus castellioides Stock, 1957

Fig. 28

Ascorhynchus castellioides Stock, 1957: 82 . Stock 1975: 968. Child 1979: 15. Stock 1986: 400. Müller 1992: 45

Material: 3.— 3 fem. (gravid), 1 juv. ( SMF 1369 ), under rocks, 0.5 m, 30.XII.1985 .

8.— 2 juv. ( SMF 1366 ), on corallinaceans on lighted jetty piles, 0–1 m, 21.IV.1985 . 1 fem. (gravid) ( INVEMAR), poriferans and hydroids on shaded jetty piles, 0–1 m, 23.IV.1985 . 1 male, 1 fem. ( SMF 1369 ), corallinaceans and hydroids on jetty piles exposed to light, 0–1 m, 24.IV.1985 . 1 male, 1 fem., 1 juv. ( ZSM), poriferans and hydroids on shaded jetty piles, 0–1 m, 24.IV.1985 . 1 juv. ( SMF 1362 ), algae and poriferans on jetty piles exposed to light, 0–1 m, 8.V.1985 . 1 fem. (gravid), 4 juv. ( ZMA 3366 ), algae and poriferans on jetty piles exposed to light, 10.V.1985 . 1 fem., 1 juv. ( USNM), poriferans and hydroids on shaded jetty piles, 0–1 m, 14.V.1985 . 1 fem. (gravid) ( SMF 1365 ), poriferans and hydroids on jetty piles exposed to light, 0–1 m, 14.V.1985 . 1 male (ov.) ( ZFMK), poriferans and hydroids on shaded jetty piles, 0–1 m, 18.V.1985 . 1 male (ov.), 1 fem., 1 juv. ( SMF 1358 ), poriferans and hydroids on shaded jetty piles, 0–1 m, 19.V.1985 . 1 fem., 1 juv. ( MNHN), hydroids and bryozoans on shaded jetty piles, 1–3 m, 21.VI.1985 . 1 juv. ( SMF 1360 ), detritus and Cnidoscyphus on jetty piles exposed to light, 0–1 m, 31.VII.1985 . 1 juv. ( SMF 1368 ), epizoans on ropes and fishing lines between jetty piles, region exposed to light 0.5–6 m, 2.VIII.1985 . 1 juv. ( SMF 1367 ), different upgrowth on jetty piles exposed to light, 0.5–6 m, 3.IX.1985 . 1 fem. (gravid) ( SMF 1364 ), different upgrowth on shaded jetty piles, 0–1 m, 17.XII.1985 . 1 juv. ( SMF 1361 ), poriferans and hydroids on shaded jetty piles, 0–1 m, 14.II.1986 .

9.— 1 male ( ZSM), coral rubble, 20–22 m, 26.I.1986 . 2 juv. ( SMF 1357 ), coral rubble covered by hydroids and bryozoans, 30 m, 10.II.1986 .

Description of male: Trunk a prolonged oval, robust, fully segmented; segments with setose and distally round or acute dorso-median tubercles. Cephalon distally with pair of tiny tubercles, with short apical seta. Ocular process cone-shaped, in centre of cephalon, as high as its basal diameter, with relatively small, distinctly pigmented eyes. Proboscis a long oval of about 2/3 trunk length. Crurigers 1–4 slightly longer than broad, separated from each other by 1/2 of their diameter, dorso-distally and laterally with some short setae. Abdomen rather short, not reaching the distal margin of coxa 2 of 4 th cruriger.

Scape of cheliphores one-articled, at the basal third bent ventrally; chelae just stumps. Palp 10-articled, 3 rd and 5 th article longer, 3 rd article somewhat longer than fifth; 5 distal articles with numerous short setae ventrally and distally. Oviger 10-articled, relatively robust; articles 4 and 5 longest, of almost same length; 4 distal articles with numerous serrated spines; terminal article with robust short claw.

Legs robust, coxa 1 of 2/3, coxa 3 of 9/10 length of coxa 2; coxa 2 bearing obtuse ventro-distal tubercle; femur slightly shorter than tibia 1, no distinct protuberances or spines; tibia 1 slightly shorter than tibia 2, numerous short and sparsely arranged setae; tarsus as long as broad, with about 7 ventral setae; propodus feebly curved and robust, 6 times as long as tarsus, dorsally about 6 longer setae in a row; sole with 13 short and feebly curved setae; main claw 1/3 length of propodus, robust and moderately curved.

Measurements: Trunk length 1.7; width (across 2 nd crurigers) 0.95; abdomen 0.6; proboscis1.4; cheliphores 0.61. B3: coxa 1, 0.24; coxa 2, 0.38; coxa 3, 0.34; femur 0.85; tibia 1, 0.95; tibia 2, 1.08; tarsus 0.16; propodus 0.75; main claw 0.3.

Remarks: After its original description the species has been recorded rather frequently. Remarkable was the frequent occurence of A. castellioides among the epifauna of piles (Stock 1957b: 82; 1975a: 968), which corresponds with the findings in the Santa Marta region. In Colombia the species was encountered along the entire research range of 0–30 depth. Contrary to the assumption of Child (1979: 15) the vertical distribution of juveniles in the research area is not deeper than that of adult specimens. Ovigerous males were encountered in small numbers in month VI.

Distribution: Western Atlantic, from Florida, Panamá to Venezuela and Barbados.

Figures

FIGURE 28. Ascorhynchus castellioides Stock,1957: A male dorsal, B male lateral, C female lateral, D male cheliphore, E male palp, F male oviger (with foliose spine further enlarged), G male leg 3.