Ammothea verenae Child 1987

How to Distinguish from Similar Species: This species is quite different from other members of the genus by being blind, by having no dorsomedian tubercles on the trunk segment cowls, and the propodus is similar on the anterior and posterior legs. Another common genus of pycnogonid found at hydrothermal vents isSericosura. Local shallow-water species of Ammothea have no strigilis.

Near hydrothermal vents

Geographical Range: Northeastern Pacific: Juan de Fuca Ridge around Axial Seamount, Endeavor Segment, and Explorer Ridge

Depth Range: Around 2000 m

Order Pantopoda is the only Order in Class Pycnogonida. Family Ammotheidae is one of the largest and most variable families of pycnogonids. Members of Family Ammotheidae usually have chelifores, but some species have no chelifores or have no chelae on them. The palps have 1 to 10 segments. Both males and females in this family have 9 to 10-segmented ovigers, which are larger in males. This species has a slender trunk, the segments of which flare out into a cowling posteriorly. The abdomen is long, and curves downward. The lateral processes from the trunk segments are separated by less than half their diameters. The legs are long and have many setae. Males have dense clusters of setae on their legs, while setae on the legs of females are much sparser. The third coxae also have long ventral setae. The distal segments on different legs are similar to one another: The tarsus is very short; the propodus is slender and curved. The main claw at the end of the legs has several long auxiliary claws. The ocular tubercle is a low cone at about the middle of the neck, without eyes. The species has a long proboscis with constrictions near the middle and at the end. The chelifores on this species are very short and without chelae. The palpi have 9 segments, the last 5 of which have many ventral setae. Oviger segments 4 and 5 are nearly equal in length. Strigilis segments 6-8 have many long lateral setae and segments 8-10 have 1-2 small denticulate spines on the end. The ovigers of females are smaller than those of males. The eggs are only about 1/4 the diameter of the oviger segments they are attached to, and are carried in large clusters. The cement gland opens as a tiny pore on the dorsodistal end of the femur.

Biology/Natural History: Common near hydrothermal vents on the Juan de Fuca Ridge. Often encrusted with metal sulfides. Segmentation in the legs of pycnogonids: The base is connected to a lateral process of the trunk. The first 3 segments are coxae 1-3, then a longer femur, then long tibia 1 and 2, tarsus, propodus, claw