Ammothella exornata Stock, 1975

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 : 24-26

Ammothella exornata Stock, 1975

Fig. 7

Ammothella exornata Stock, 1975: 974 .

Ammothella exornata — Child 1979: 9. Stock 1979: 975. Child 1982: 358. Stock 1986: 400. Müller 1990: 278.

Material: 10.— 4 juv. ( SMF 1218 ), algae growing on rock, mesolittoral, 10.V.1985 .

19.— 19 males (12 ov.), 13 fem. (gravid), 4 juv. ( SMF 1219 ), Thalassia , 5 l of substrate, 0.5–4 m, 27.VI.1985 . 1 male, 1 juv. ( ZSM), same locality, 5.VII.1985 . 4 males (1 gravid), 3 fem. (gravid), 3 juv. ( ZFMK), same locality, 13.VIII.1985 . 3 fem. (gravid) ( USNM), same locality, 8.XI.1985 . 6 juv. ( SMF 1220 ), same locality, 7.XII.1985 . 1 juv. ( SMF 1221 ), same locality, 7.I.1986 . 5 juv. ( SMF 1222 ), same locality, 12.II.1986 . 1 juv. ( SMF 1223 ), same locality, 3.III.1986 . 2 males, 1 fem. (gravid), 3 juv. ( ZMA 3351 ), same locality, 2.IV.1986 .

24.— 2 males, 1 fem. (gravid), 6 juv. ( INVEMAR), Thalassia with corallinaceans and Cnidoscyphus , 1–2 m, 9.VIII.1985. 1 male (ov.), 1 juv. ( SMF 1224), Thalassia with corallinaceans, 2 m, 4.IX.1985. 2 fem. (1 gravid) ( MNHN). Thalassia , 1 m, 4.IX.1985. 2 males (1 ov.), 2 fem., 2 juv. ( ZSM), Thalassia , 0.5–1 m, 8.IX.1985. 8 males (3 ov.), 6 fem. (4 gravid), 31 juv. ( SMF 1225), Thalassia with corallinaceans, 1 m, 21.I.1986.

27.— 1 male ( SMF 1226 ), Thalassia with coral rubble, 0.5 m, 13.IX.1985 . 9 males (1 ov.), 6 fem. (gravid), 10 juv. ( SMF 1227 ), coral rubble among Thalassia , 1 m, 1.XI.1985 .

30.— 9 males (1ov.), 6 fem. (gravid), 1 juv. ( SMF 1228 ), Thalassia , 2 m, 29.V.1985 . 3 males (ov.), 4 fem. (3 gravid), 2 juv. ( SMF 1229 ), same locality, 6.VI.1985 . 10 males (4 ov.), 6 fem. (5 gravid), 5 juv. ( SMF 1230 ), same locality, 4.VII.1985 . 4 juv. ( SMF 1231 ), same locality, 0.5–2 m, 11.IX.1985 . 3 males, 2 fem. (gravid) ( SMF 1232 ), same locality, 1–2 m, 4.X.1985 . 2 males (1 ov.), 3 fem. (gravid), 14 juv. ( SMF 1233 ), same locality, 2–3 m, 4.XII.1985 . 5 males (3 ov.), 4 fem. (3 gravid), 33 juv. ( SMF 1234 ), same locality, 1–2 m, 17.I.1986 . 7 males (6 ov.), 6 fem. (5 gravid), 7 juv. ( SMF 1235 ), same locality, 1–3 m, 24.I.1986 . 3 juv. ( SMF 1236 ), same locality, 1–2 m, 9.II.1986 .

33.— 1 fem. (gravid) ( SMF 1237 ), Thalassia , 0.5 m, 14.XI.1985. 13 juv. ( SMF 1238 ) , same locality, 17.I.1986 .

43.— 41 males (7 ov.), 23 fem. (17 gravid), 66 juv. ( SMF 1239 ), Thalassia , 1–1.5 m, 25.II.1986 .

44.— 4 males (2ov.), 3 fem. (1gravid), 3 juv. ( SMF 1240 ), Syringodium , 25.II.1986 .

Description of male: Trunk compact, of nearly circular outline, segments 3 and 4 fused. Crurigers almost touching each other. Ocular process about four times as tall as its basal diameter, distally terminating in tiny tip. Eyes clearly pigmented. Cephalon bearing small tooth-like tubercle on lateral margin of ocular process and long slender process on its distal side; cephalon with several additional small tubercles above origin of palps. All crurigers dorsodistally and dorso-laterally with several partly ramified tubercles. Vertical finger-like tubercles on dorsal hind margin of trunk segments 1 and 2. Abdomen antero-basally with similar process split at its base; short tooth-like tubercle dorso-distally on abdomen; in dorsal view, abdomen reaching by half of its length over 4 th crurigers, directed obliquely upwards; distally narrowed with some short setae.

Proboscis very robust, oval in outline.

Cheliphore scape two-articled, dorsally with several tubercles: 1st article bearing one dorsodistal seta, 2 nd 3–7 finely pinnate setae; cheliphore stumps dorsally adorned with one finely pinnate seta. Palps 9-articled, 2 nd article longest; articles 7–9 shortened and of almost equal length, densely beset with pinnate setae on ventral or distal margin of articles 5–9. Oviger 10-articled; articles 4 and 5 elongated and of subequal length; 9th and 10th tiny terminal article with flat spines with serrated edges. Legs relatively short and robust; coxae 1 of all legs with several dorso-distal and dorso-lateral tubercles and setae; coxae 2 of legs 3 and 4 with slender ventro-distal genital tubercle; coxae 1–3 of legs 1–4 of nearly equal length; femur robust, only twice as long as broad; short cement gland duct of about 1/5 of femur length on its dorsodistal aspect; tibia 1 about as long as femur, but slenderer; tibia 2 only 4/5 as long as tibia 1; in addition to rich covering by short setae tibia 1 adorned with 2 dorsal spines, tibia 2 with one dorsal spine; tarsus slightly longer than broad, with 2 short ventral spines; propodus rather strongly curved, without heel; sole proximally with 3 robust spines, distally with 5–7 more slender spines; main claw about 2/3 lenghth of propodus, moderately curved; auxiliaries about 1/2 length of main claw.

Measurements: Length of trunk 0.65; width (across 2 nd crurigers) 0.65; length of abdomen 0.33; proboscis length 0.61; length of cheliphora 0.41. Leg 3: coxa 1, 0.11; coxa 2, 0.14; coxa 3, 0.14; femur 0.37; tibia 1, 0.37; tibia 2, 0.35; tarsus 0.07; propodus 0.31; main claw 0.20; auxiliary 0.09.

Female: In habitus very similar to males, coxae 2 of legs 3 and 4 without the male genital excrescence. Femora enlarged to contain the ova, so their breadth about 3/5 times their length. Oviger in its entirety much less setose than in the males.

Remarks: The species is closely related to Ammothella menziesi Hedgpeth, 1951 from California (Stock 1975a: 978). A. menziesi is most easily distinguished from A. exornata by the lack of finger-like processes at the bases of ocular process and abdomen (compare: Hedgpeth 1951: 109, Pl.2).

A. exornata in this region is a species confined to shallow water, which was encountered here (with the exception of several juveniles) in meadows of seagrass only. Ovigerous males were found all year round, the months III–IV and X excepted.

Distribution: Found only in the Caribbean region.— St. Martin and Bonaire (Stock 1975a: 975), Panamá ( Child 1979: 9), Belize (Child 1982: 358), Martinique ( Müller 1990d: 278) and Colombia.

Figures

FIGURE 7. Ammothella exornata Stock, 1975: A male lateral, B male dorsal, C male cheliphore, D male palp, E female oviger, F male oviger, G five distal article of male oviger, H male leg 4, I female leg 4.