Pliciloricus hadalis
ORDER
Nanaloricida
FAMILY
Pliciloricidae
TAXONOMY
Pliciloricus hadalis Kristensen & Shirayama, 1988, Izu-Ogasawara Trench, Western Pacific.
OTHER COMMON NAMES
None known.
PHYSICAL CHARACTERISTICS
Adults measure 0.0058–0.0086 in (149–219 µm). The males are smaller than the females. Mouth cone is small and without mouth tube. The leg-shaped scalids in the second row are very large and robust. Two of the scalids in the second row are modified into a short and thick double organ. The fourth row has 15 claw-shaped scalids and 15 simple spinoscalids. The trichoscalids (eight single and seven double) are very long, about 0.0039 in (100 µm). The abdomen consists of 20 plicae. A single pair of Pliciloricus-flosculi is located caudally. Higgins larvae are long and slender, measuring 0.0103 in (262 µm). There are seven rows of scalids. The spinoscalids are long, over 0.00197 in (50 µm). Two pairs of setae are situated between the thorax and the abdomen. The toes are very long, about 0.006 in (153 µm), straight and pointed. Three pairs of setae are located toward the rear of the abdomen.
DISTRIBUTION
The hadal bathymetric zone of the deep sea (below 20,000 ft; 6,100 m). Found in the Izu-Ogasawara Trench off Japan at a depth of 27,100 ft (8,260 m).
HABITAT
Red deep-sea clay.
BEHAVIOR
One specimen was found 1.57 in (4 cm) deep in the clay, which indicates that the animal is capable of burrowing or living in association with a tube-dwelling macrofauna animal.
FEEDING ECOLOGY AND DIET
Probably bacteria.
REPRODUCTIVE BIOLOGY
The mode of reproduction of this species is not understood. The lack of seminal receptacles in the female suggests that this species has external fertilization.
CONSERVATION STATUS
Not listed by the IUCN.
SIGNIFICANCE TO HUMANS
None known.
