No common name

Desmoscolex squamosus

ORDER

Desmoscolecida FAMILY

Desmoscolecidae TAXONOMY

Protricomoides squamosus Timm, 1970.

OTHER COMMON NAMES None known.

PHYSICAL CHARACTERISTICS

Characterized by the annulation and ornamentation of the body cuticles, the shape of the head, the shape and arrangement of the somatic setae, and the copulatory apparatus. They have a small body that is tapered at both ends; the female body is longer than the male. The cuticle is annulated, with only the two anterior and the three posterior main rings being considered complete; that is, they are covered with a continuous narrow or wide layer of secretion and concretion material. The body cuticle has 70-71 annules (when counting complete main rings as single annules) in the holotype male and 73 annules in the paratype female. The annules contain a transverse row of minute pores with a small accumulation of secretion and concretion particles around them. at the level of the insertion of the somatic setae, the layer of concretion is larger.

The somatic setae are arranged in pairs, inserted on short peduncles or almost directly on the body cuticle, but they differ sub-dorsally and sub-ventrally. The sub-dorsal setae taper distally to a shorter spatulate tip, which is 0.0000787-0.000118 in (2-3 pm) in length. The sub-ventral setae are shorter than the sub-dorsal ones, and are all about equally long, except for the longer elongated terminal pair of sub-dorsal setae. The head is generally wider than long, with a wide truncated anterior end. The cuticle is thickened and sclerotized, except in the labial region and at the level of the amphids. From the insertion of the cephalis setae to about halfway along the head length, the cuticle is covered with concretion material. The labial zone has six papillae that are very small. the cephalic setae is jointed, with a length of 0.000118-0.000158 in (3-4 pm) at the base and a fine distal part.

Amphids are rounded and vesicular, mostly covering the head. The amphidial opening is large, and situated in the posterior region of the head. The digestive system is typical for its genus. the stoma is very small. The pharyngo-intestinal junction is opposite the posterior end of the second main ring. The intestine overlaps the rectum by a large blind sac, extending to halfway to the end ring of the paratype female. There are very small ochrous pigment spots situated at the level of annule 13. The cloacal tube protrudes from the ventral body wall in annule 64. Spicules are about 0.000945 in (24 pm) in length, and gradually taper to a tip. the gubernaculum is not observed. The tail has two main rings, with females also having two partial rings. The phasmata is not observed.

DISTRIBUTION

Not known; although the family Demoscolecida is found primarily in marine waters and occasionally in freshwater and soil. (Specific distribution map not available.)

HABITAT

Nothing is known.

BEHAVIOR Nothing is known.

FEEDING ECOLOGY AND DIET

Nothing is known.

REPRODUCTIVE BIOLOGY

The reproductive system is typical for the genus. It is obscured because of the very enlarged intestine that contains many large globules. The female vulva is situated within annule 48. Males have one testis.

CONSERVATION STATUS Not listed by the IUCN.

SIGNIFICANCE TO HUMANS None known. ♦

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