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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Tenagodrilus

Tenagodrilus Eckroth & Brinkhurst, 1996 (ref. ID; 6615 original paper)

Family Lumbriculidae (ref. ID; 6615)

ref. ID; 6615

Genus of family Lumbriculidae with testes paired in IX and X, ovaries paired in XI, atria paired in X, spermathecae one pair in IX, sometimes an additional pair in VIII. Posterior vasa deferentia enter XI before reentering X. Atria with complex penial musculature and ejaculatory ducts between ampullae and pendant penes Male and spermathecal pores very large, located immediately behind the ventral setae. Blind-ending lateral extensions of the commissural blood vessels present in posterior segments. (ref. ID; 6615)

Etymology

Tenago - Gr., living in pools, -drilus - worm. (ref. ID; 6615)

Type species (by monotypy)

Tenagodrilus musculus Eckroth & Brinkhurst, 1996 (ref. ID; 6615)
  1. Tenagodrilus musculus Eckroth & Brinkhurst, 1996 (ref. ID; 6615 original paper)

Tenagodrilus musculus Eckroth & Brinkhurst, 1996 (ref. ID; 6615 original paper)

Descriptions

Live specimens grayish red-brown, opaque. Body length, mature individuals (preserved) 22-82 mm, width 0.5-1.3 mm at the clitellum, number of segments 90-297. Prostomium bullet-shaped, annulation slight, not doubled. Setae paired, simple-pointed, sigmoid with nodulus. Some ventral setae with very slight indication of a rudimentary uper tooth, slightly exaggerated in the illustration. Setae become progressively longer and thinner to mid body, but are as short as in II in posterior segments. Setal formula (X) 50:2:7:105 (Reynolds 1977). Cuticle colorless and thin. Clitellum inconspicuous, extending over IX-XII or parts thereof. Spermathecal pores large (32 µm anterior to posterior; 56 µm side to side), posterior, and in line with, ventral setae, close to posterior margin of IX. In 10% of specimens, a second pair of spermathecal pores in VIII, the same in position and size. Equally large pair of male pores in X posterior and in line of ventral setae. One pair inconspicuous female pores (8 µm anterior to posterior, 40 µm side to side) in intersegmental furrow 11/12. Eversible pharyngeal pad thick dorsally, muscles slightly developed, cuticulate anteriorly but pharynx heavily ciliated from III to V, pharyngeal glands from II to V. Pharynx floor thin and cuticulate. Chloragogen begins in V. Dorsal blood vessel divides in prostomium to form two ventro-lateral vessels that unite in V. Two vessels leave dorsal vessel to supply supraoesophaegal ganglia. In anterior segments to X, commissural vessels long and convoluted. In post reproductive segments, one pair of thick commissural vessels per segment to XIV. Hearts from XIV to XVI. After XIX, commissural vessels two pairs per segment; by XXX both pairs of commissural vessels bear blind-ending lateral vessels which enter the muscular body wall and return to terminate in the coelom as small bulbs. Mature specimens with long vessels penetrating sperm and egg sacs. Testes paired in IX and X, paired sperm sacs penetrate to XVI. Sperm funnels conspicuous in IX and X, first pair anterior on 9/10 behind spermathecal ampullae, second pair in sperm sacs of X, located within XI. Anterior sperm funnels penetrate 9/10 laterally, vasa deferentia follow ventral wall of X, and run posteriad to medial aspects of penis musculature. Each anterior vas deferens ascends through penial musculature to penetrate atrial ampulla just above base, opening into atrium subapical after running through atrium wall muscles. Posterior prosoporous vasa deferentia begin on anterior of 10/11, grow through the septa, descending ventrally. From there, each runs along ventral wall to reenter X close to the penial musculature, then enters the atrium following a path similar to that of the anterior pair but on lateral side of atrium. The posterior sperm funnels often drown posteriad into the sperm sacs. Atrial ampullar spherical with thin muscular walls and thin outer layer of prostate cells. The rest of each male duct, consisting of ejaculatory duct and long pendant penis in large sac, enclosed in a muscular complex that surrounds the atrial ampulla. Retractor muscles originate in dorsal body wall and insert between ampullae and penis sacs. When retractor muscles relaxed, the ampullae lie above penes with retractor muscles on each side when contracted, atrial ampullae are reflected posteriad. This also results in coiling of the ejaculatory duct. Protractor muscles originate on the ventral body wall, and insert between the atrial ampulla and the ejaculatory duct. When contracted, the penes protrude and ejaculatory ducts are straightened. Penes about four times longer than broad, without visible cell bodies or nuclei. Ovaries paired in XI, extending to XII. Egg sacs from XI extending to XVII or XIX. Female funnels large and obvious, opening in 11/12. In immature individuals there is a second pair of rudimentary ovaries but no female funnel. These ovaries are not present in the mature specimens. Spermathecae paired in IX, a second pair in VIII in 10% of worms. Spermathecal ducts leave posterior subapical walls of large vestibules to enter voluminous ampullae anteriorly. Ampulle may be reflected through 9/10 into anterior part of X, the atrial complex lying well posterior in X; alternatively ducts reflected anteriad along the floor of IX with ampullae reflected over them dorsally and posteriad. (ref. ID; 6615)

Etymology

musculus - referring to muscular complex of male ducts. (ref. ID; 6615)

Type locality

WEUP Pond, intersection of Sparkman and Jordan, Huntsville, Alabama, USA, RIW-T3S, -section 21. Madison Co. AL, coll. Richard Modlin, December 1983 to April 1987, coll. M.C.E. December through April, 1991 to 1993. (ref. ID; 6615)

Type materials

  • Holotype: USNM171060, a whole animal in 70% alcohol, from the type locality, coll. R. Modlin, 02/01/1987. (ref. ID; 6615)
  • Paratypes: USNM171061, 171062, 10 whole animals in fluid with one pair of spermathecae, two whole animals with two pairs of spermathecae, from the same collection as the holotype; M.C.E. collection: 17 specimens, 2 of which mature, from the same collection. (ref. ID; 6615)
  • Other materials: