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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Grania

Grania Southern, 1913 (ref. ID; 5952, 5967)

Family Enchytraeidae (ref. ID; 5952, 6602)

ref. ID; 5967

Remarks

Species of Grania are easily recognized by their smooth, thickly cuticularized bodies. The setal distribution of the genus is also characteristic, at most one seta representing a bundle, setae entirely absent in at least the three most anterior segments, and lateral setae (if present) commencing in segments posterior to the first ventral bundles. Grania was the subject of a recent taxonomic revision by Erseus and Lasserre (1976). A generic definition with some minor amendments was published by Jamieson (1977). Recently (Coates and Erseus 1980; Erseus 1980) three new species of Grania, two from habitats in British Columbia, have been described which have glandular cells associated with the spermathecal ectal duct. Two types of compact penial bulb are now known to occur in Grania (Erseus 1977). One type has a large mass of glandular tissue on its dorsal surface and the other is without this mass. The supraspecific taxonomic stability of these bulb types has not been investigated. At least one species, Lumbricillus codensis Lasserre, 1971, is thought to belong in a genus closely related to Grania. This species has ventral setae from II, one per bundle and a preclitellar, unlobed seminal vesicle. (ref. ID; 5967)

Distribution

Cosmopolitan; marine intertidal and subtidal. (ref. ID; 5967)

Type species

Grania maricola Southern, 1913 (ref. ID; 5967)
  1. Grania americana (Kennedy, 1966) (ref. ID; 6655)
  2. Grania atlantica Coates & Erseus, 1985 (ref. ID; 6602)
  3. Grania bermudensis (Erseus & Lasserre, 1976) (ref. ID; 6655)
  4. Grania hylae (Lock & Coates) (ref. ID; 6655)
  5. Grania incerta Coates and Erseus, 1980 (ref. ID; 5858, 5952 original paper, 5967)
  6. Grania laxarta (Locke & Coates) (ref. ID; 6655)
  7. Grania levis Coates & Erseus, 1985 (ref. ID; 6602)
  8. Grania longiducta Erseus & Lasserre, 1976 (ref. ID; 6602)
  9. Grania macrochaeta (Pierantoni, 1901) (ref. ID; 6913)
  10. Grania macrochaeta bermudensis Erseus & Lasserre, 1976 (ref. ID; 5858)
  11. Grania macrochaeta pusilla Erseus, 1974 (ref. ID; 5858)
  12. Grania macrochaeta trichaeta Jamieson, 1977 (ref. ID; 5858)
  13. Grania maricola Southern, 1913 (ref. ID; 5858, 5967)
  14. Grania monospermatheca Erseus & Lasserre, 1976 (ref. ID; 5858, 6602)
  15. Grania pacifica Shurova, 1979 (ref. ID; 5858)
  16. Grania paucispina (Eisen, 1904) (ref. ID; 5858, 5962, 5967)
    Syn; Michaelsena paucispina Eisen, 1904 (ref. ID; 5952)
  17. Grania postclitellochaeta longiducta Erseus & Lasserre, 1976 (ref. ID; 5858)
  18. Grania postclitellochaeta postclitellochaeta (Knollner, 1935) (ref. ID; 5858)
  19. Grania pusilla Erseus, 1974 (ref. ID; 6619)
  20. Grania raeducta Coates & Erseus, 1985 (ref. ID; 6602)
  21. Grania roscoffensis Lasserre, 1967 (ref. ID; 5858)
  22. Grania variochaeta Erseus & Lasserre, 1976 (ref. ID; 5858)

Grania atlantica Coates & Erseus, 1985 (ref. ID; 6602)

Habitat

Marine species. (ref. ID; 6602)

Grania incerta Coates and Erseus, 1980 (ref. ID; 5858, 5952 original paper, 5967)

Descriptions

The species conforms to the generic definition (Erseus and Lasserre 1976; slightly emended by Jamieson 1977). Only the more specific characters are described here. Filiform and smooth species. Length (six complete, mature, fixed specimens) 6.9-10.3 mm, 47-55 segments. Diameter in slightly compressed, whole-mounted specimens; about 0.2 mm, slightly less in most posterior segments. Setae proximately broad and slightly curved. Ventral setae beginning in IV, dorsal setae beginning in XVIII or XIX. Posterior setae about twice as long as anterior setae. Anterior setae sharply tapered, posterior ones very thick with pointed tips. Supplementary setae absent. Three pairs of primary septal glands at IV/V, V/VI, and VI/VII. Secondary septal glands especially well developed in VI. Dorsal vessel originating in XV-XIX. Seminal vesicle extending backwards as far as XVII. Sperm funnel two to four times longer than wide. Vas deferens thin and coiled, extending into XIV. Penial bulb compact, enclosed in muscles, of small to medium size, ratio of body width of XII to bulb diameter is two and a half to four. Bulb without a large mass of glandular tissue on dorsal surface. Spermathecal pores paired, located laterally in most anterior part of V. Spermathecae with narrow ectal duct and large, pear-shaped to ovoid ampulla. Orifice of ectal duct surrounded by a few multinucleate glands. Ampulla moderately incised at junction with ectal duct, entally attached to oesophagus near V/VI, probably with a narrow connecting canal numerous aggregates of sperm dispersed within wall of ampulla. (ref. ID; 5952)

Remarks

There are very slight morphological differences between the specimens of the two geographical areas represented in the material examined. The Californian worms are slightly longer (8.5-10.3 mm, 52-55 segments; four specimens that are complete and mature) than those from British Columbia (6.9-7.2 mm, 47-50 segments; two complete and most mature of four specimens). However, even the two most mature worms from British Columbia have poorly developed seminal vesicles and eggs, and their spermathecae contain few or no spermatozoa and probably, they are not fully grown. The dorsal setae commence in XVIII in all individuals from British Columbia. In the remaining specimens, the dorsal setae commence in XIX. Grania incerta sp. n. is distinguished from G. paucispina by its consistently more posterior location of the first dorsal setae and by its more filiform and typical "Grania-like" body. A distinction is also to be seen in the spermathecae. The incision of the spermathecal ampulla at the entrance of the ectal duct appears to be more pronounced in G. paucispina than in G. incerta. (ref. ID; 5952)

Grania incerta was described from sublittoral sand samples collected both in British Columbia and in California. Distinguishing characteristics have been discussed with regards to G. paucispina (Eisen). (ref. ID; 5967)

Habitat

Sublittoral marine sands, known from 3-16 m depth. (ref. ID; 5952)

Etymology

Specific name for Latin "incertus" = uncertain, doubtful, etc. A species of somewhat ancertain taxonomic rank. (ref. ID; 5952)

Type locality

Santa Barbara, California, U.S.A.; natural oil seep east of Coal Oil Point (Isla Vista Seep), 34 degrees 24'30"N, 119 degrees 52'10"W, well-sorted fine sand at 16 m depth (coll. by R.B. Spies et al., holotype from Oct. 1977, paratypes from May and Oct. 1977). (ref. ID; 5952)

Examined materials

  • Holotype: USNM58908, whole-mounted, fully mature specimen. (ref. ID; 5952)
  • Paratypes: USNM58909, four mature and one inmature, whole-mounted specimens from the type locality. USNM58910, four more or less mature, whole-mounted specimens from north tip of Rennison Island (near Caamano Sound), 52 degrees 50'22"N, 129 degrees 20'49"W. British Columbia, Canada; well-sorted sand, 3 m depth (coll. Oct. 21, 1978, by H.R. Baker). (ref. ID; 5952)

    Grania levis Coates & Erseus, 1985 (ref. ID; 6602)

    Habitat

    Marine species. (ref. ID; 6602)

    Grania longiducta Erseus & Lasserre, 1976 (ref. ID; 6602)

    Habitat

    Marine species. (ref. ID; 6602)

    Grania monospermatheca Erseus & Lasserre, 1976 (ref. ID; 5858, 6602)

    Habitat

    Marine species. (ref. ID; 6602)

    Grania paucispina (Eisen, 1904) (ref. ID; 5858, 5962, 5967)

    Synonym

    Michaelsena paucispina Eisen, 1904 (ref. ID; 5952)

    Descriptions

    The species conforms to the generic definition (Erseus & Lasserre 1976; slightly emended by Jamieson 1977). Only the more specific characters are described here. Slender species, but not as filiform and smooth as many other Grania forms. Length (fixed specimens) 5.5-7.1 mm, 35-45 segments. Diameter in slightly compressed, whole-mounted specimens, about 0.2 mm throughout body. Setae proximately broad and slightly curved. Ventral setae beginning in IV, dorsal setae beginning in XIII or XIV. Posterior setae about twice as long as anterior setae. Anterior setae sharply tapering, posterior ones very thick with pointed tips. Supplementary setae absent. Three pairs of primary septal glands at IV/V, V/VI, and VI/VIII. Secondary septal glands especially well developed in VI. Dorsal vessel originating in XIV-XV. Seminal vesicle extending posteriorly into anterior to XIV. Sperm funnel about three times longer than wide. Vas deferens thin and coiled, extending into XIV. Penial bulb compact, of small to medium size, ratio of body width of XII to bulb diameter is about three. Bulb without a large mass of glandular tissue on dorsal surface (Erseus 1977). Spermathecal pores paired, located laterally in most anterior part of V. Spermathecae with narrow ectal duct and large, ovoid to pear-shaped ampulla. A few multinucletae glands closely associated with duct near orifice. Ampulla very deeply incised at junction with duct, and entally attached to oesophagus near V/VI, probably with a narrow connecting ental canal. Small aggregates of spermatozoa dispersed within wall of ampulla. (ref. ID; 5952)

    Remarks

    Eisen's (1904) description is very brief, but since he accounted for the species' spermathecae and setal distribution (the two basic characteristics for the identification of species of Grania according to Erseus and Lasserre (1976, 1977) there is no doubt about the identity our new material. (ref. ID; 5952)

    An amended description of G. paucispina Eisen has recently been published by Coates and Erseus (1980). Grania paucispina Eisen can be distinguished from G. incerta Coates and Erseus, the only other species of Grania presently recorded from British Columbia, by the presence in G. paucispina of lateral setae from XIII or XIV, in G. incerta they begin a few segments posteriad, XVII-XIX. The spermathecae of the two are also slightly different with those of G. paucispina being more incised by the ectal duct at its junction with the ampulla. (ref. ID; 5967)

    Habitat

    Littoral and marginally sublittoral (down to 6 m), muddy sand for Victoria specimens marine or brackish water. (ref. ID; 5952)

    Material examined

    Two preserved, whole-mounted mature specimens. One from Tomales Bay (between White Gulch and Hog Island), California, U.S.A., 38 degrees 11'45"N, 122 degrees 56'13"W, 6 m, coll. Oct. 30, 1955 by M.L. Jones (USNM Cat. No.58906). One from Victoria Inner Harbour, British Columbia (48 degrees 28'41"N, 123 degrees 22'16"W); subtidal, 2 m depth, muddy sand with much organic material, sample site located immediately below a domestic waste outfall, brackish water, coll. Mar. 2. 1978 by H.R. Baker (USNM 58907). (ref. ID; 5952)

    The original type material deposited at CASF was destroyed in 1906. (ref. ID; 5967)

    Grania raeducta Coates & Erseus, 1985 (ref. ID; 6602)

    Habitat

    Marine species. (ref. ID; 6602)