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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Dero

Dero Oken, 1815 (ref. ID; 1257, 3692, 6913)

Family Naididae (ref. ID; 5876, 5939, 6600, 7854)

Family Naididae: Subfamily Naidinae Lastockin, 1924 (ref. ID; 1257)

ref. ID; 1663

Some capilliform setae in dorsal bundles. With ciliated posterior gills surrounding the anus. (ref. ID; 1663)

ref. ID; 1923

Posterior end modified into a gill bearing respiratory organ, the branchial area; usually living in tubes. Branchial area without long processes or palps. (ref. ID; 1923)
  1. Dero abranchiata (ref. ID; 5939)
  2. Dero asiatica Cernosvitov, 1930 (ref. ID; 3692)
  3. Dero bilongata Chen (ref. ID; 1663)
  4. Dero borellii Michaelsen, 1900 (ref. ID; 6616)
  5. Dero botrytis Marcus, 1943 (ref. ID; 6913)
  6. Dero cooperi Stephenson, 1932 (ref. ID; 6913) reported author and year? (ref. ID; 6580)
  7. Dero digitata (O.F. Muller, 1773) (ref. ID; 1257, 1663, 1923, 3692, 5939, 6554, 6913, 7854)
    Syn; Dero mulleri Bousfield, 1886 in Southern (1909) (ref. ID; 1257); Dero limosa Leidy, 1852 (ref. ID; 1257, 1923)
  8. Dero dorsalis Ferroniere, 1899 (ref. ID; 1257, 3692)
  9. Dero evelinae Marcus, 1943 (ref. ID; 6913)
  10. Dero flabelliger (ref. ID; 5939)
  11. Dero floridana (ref. ID; 5939)
  12. Dero furcata Oken, 1815 (ref. ID; 1257, 1928)
  13. Dero (A.) furcata (O.F. Muller, 1773) (ref. ID; 6618) reported year? (ref. ID; 6913)
  14. Dero furcatus (O.F. Muller, 1773) (ref. ID; 6616) reported year? (ref. ID; 1663) reported author and year? (ref. ID; 5939)
  15. Dero hylae (ref. ID; 5939)
  16. Dero indica Naidu, 1962 (ref. ID; 6651)
  17. Dero indicus Michaelsen, 1911 (ref. ID; 6616)
  18. Dero intermedia Loden & Harman, 1982
    See; Dero lodeni (ref. ID; 6554)
  19. Dero latissima Bousfield, 1886 (ref. ID; 1257, 1928)
  20. Dero limosa Leidy (ref. ID; 1928)
    See; Dero digitata (ref. ID; 1257, 1923)
  21. Dero lodeni Brinkhurst, 1986 (ref. ID; 6554)
    Syn; Aulophorus pectinatus Stephenson, 1931 (ref. ID; 6554); Dero intermedia Loden & Harman, 1982 (ref. ID; 6554)
  22. Dero mulleri Bousfield (ref. ID; 1928)
    See; Dero digitata (ref. ID; 1257)
  23. Dero multibranchiata Stieren, 1892 (ref. ID; 6554, 6913)
  24. Dero nivea Aiyer, 1929 (ref. ID; 3692, 5939, 6913) or 1930 (ref. ID; 1257, 6618, 6554)
  25. Dero nivea Sperber (ref. ID; 1663)
  26. Dero oblongata (ref. ID; 6580)
  27. Dero obtusa d'Udekem, 1855 (ref. ID; 1257, 1663, 1923, 1928, 3692, 6913, 7854) reported author and year? (ref. ID; 5939)
  28. Dero palmata Aiyer, 1929 (ref. ID; 6616)
  29. Dero pectinata Aiyer, 1929 (ref. ID; 1326) reported author and year? (ref. ID; 5939)
  30. Dero perrieri Bousfield, 1886 (ref. ID; 1257, 1928)
  31. Dero plumosa Naidu, 1962 (ref. ID; 6913)
  32. Dero raviensis (Stephenson, 1914) emend. Grimm, 1985 (ref. ID; 6554)
    Syn; Nais raviensis Stephenson, 1914 (ref. ID; 6554)
  33. Dero roseola Nicholls, 1921 (ref. ID; 1257)
  34. Dero sawayai Marcus, 1943 (ref. ID; 6616)
  35. Dero vaga (Leidy) (ref. ID; 6913)
  36. Dero vagus Leidy, 1880 (ref. ID; 6554) reported year? (ref. ID; 1663) reported author and year? (ref. ID; 5939)

Dero bilongata Chen (ref. ID; 1663)

Descriptions

Branchial fossa without long palps. Asexual reproduction by fragmentation. Ventral setae all of one shape. Rare species. (ref. ID; 1663)

Dero digitata (O.F. Muller, 1773) (ref. ID; 1257, 1663, 1923, 3692, 5939, 6554, 6913, 7854)

Synonym

Dero mulleri Bousfield, 1886 in Southern (1909) (ref. ID; 1257); Dero limosa Leidy, 1852 (ref. ID; 1257, 1923)

Descriptions

Branchial fossa without long palps. Asexual reproduction by budding. Ventral setae of II to V sharply differentiated from those of other segments. With four pairs of gills or gill-like structures. Very common. (ref. ID; 1663)

Normally 4 pairs of gills; distal bifurcation of dorsal needle setae longer than proximal. (ref. ID; 1923)

Remarks

This large and common species has an elaborate synonymy and the range of chaetal measurements in the literature is correspondingly large. The dimensions on the examined material were as follows: anterior ventrals 120-139 µm, posterior ventrals 79-120 µm, needles 75-95 µm, hairs 222-326 µm. These values agree with those for specimens from Surinam described by Harman (1974), the only other South American material available. (ref. ID; 6554)

New record

Peru: Lake Yarinacocha, February 1965, and Curanja Balta River, Depto. Loreto, August 1966, coll. J. O'Neill, A.L. Gardner, 10 specimens, W.J. Harman collection. (ref. ID; 6554)

Dero furcatus (O.F. Muller, 1773) (ref. ID; 6616) reported year? (ref. ID; 1663) reported author and year? (ref. ID; 5939)

Descriptions

Branchial fossa with two long palps. Dorsal setae beginning on V. (ref. ID; 1663)

Dero lodeni Brinkhurst, 1986 (ref. ID; 6554)

Synonym

Aulophorus pectinatus Stephenson, 1931 (ref. ID; 6554); Dero intermedia Loden & Harman, 1982 (ref. ID; 6554)

Descriptions

Dorsal chaetae from V, 1 hair and 1 bifid needle 280 µm and 102 µm long, respectively, the needles bifid with 2-4 intermediate teeth. Ventral chaetae 3 or 4 per bundle, 2 or 3 posteriorly, 106-140 µm, nodulus more or less distal, teeth the same length, the lower ones thicker. Four pairs of gills, one pair of short diverging palps. (ref. ID; 6554)

Remarks

The specimens examined here are very long, with up to 204 chaetigerous segments and a 300 µm long caudal portion not yet segmented. The hairs are up to 260 µm long, the needles, 124-148 µm, the anterior and posterior ventrals, 110-139 and 118-160 µm long, respectively. The anterior ventral chaetae have the upper teeth longer and thinner than the lower, but the posterior chaetae have teeth of equal length, unlike the original description. The needles are massive, in some segments longer than the ventral chaetae, and have a distal nodulus. They are 6-7 µm wide, and make the hairs seem unusally short and thin. The hair chaetae may vary from 0 to 3 per bundle and there may be 5-7 anteriorly ventrals. Some of the posterior ventrals have the upper tooth shorter than the lower. (ref. ID; 6554)

New record

Argentina: San Javier River, Santa Fe Province, 1984, coll. U. Molet and M. Marchese, 6 specimens. (ref. ID; 6554)

Dero multibranchiata Stieren, 1892 (ref. ID; 6554, 6913)

Remarks

The large number of gills could not be accurately counted in these mounted specimens, but clearly was more than the usual 2 or 3 pairs of most species and far less than the 40 of D. botrytis. The chaetal measurements were as follows: anterior ventrals 130-136 µm, posterior ventrals 77-89 µm, needles 80-86 µm, hairs 184-225 µm. The hairs are longer than those previously reported. The material was too poorly preserved to allow a more complete description. (ref. ID; 6554)

New record

Peru: Amazon Camp Resort, Amazon River Basin above Iquitos, 29 April 1984, coll. R.O. Brinkhurst, 5 specimens. (ref. ID; 6554)

Dero nivea Aiyer, 1929 (ref. ID; 3692, 5939, 6913) or 1930 (ref. ID; 1257, 6618, 6554)

Remarks

In this material the chaetal measurements were as follows: anterior ventrals 65-83 µm, posterior ventrals 59-68 µm, needles 41-56 µm, hairs 140-160 µm. Specimens from Surinam (Harman 1984) had shorter hairs and needles. (ref. ID; 6554)

New record

Argentina: Saladillo River, Santa Fe Province, October-November 1984, 3 specimens; San Juan River, San Juan Province, 14 May 1986; La Vina dam, Cordoba Province, 16 May 1986; Uragua-i and False Uragua-i rivers, Missiones Province, August 1986, 1 specimen; Termas de Rio Hondo, Santiago Province, 10 May 1986, coll. E. Drago, U. Molet, R. Regner, and M. Marchese. Peru: Laguna Huacarpay, Depto, Cusco, September 1978, coll. J. O'Neill, 4 specimens, W.J. Harman collection. (ref. ID; 6554)

Dero nivea Sperber (ref. ID; 1663)

Descriptions

Branchial fossa elongated without long palps. Asexual reproduction by budding. Ventral setae of II to V sharply differentiated from those of other segments. Three pairs of gills or two pairs and one pair of ciliated swellings. Rare species. (ref. ID; 1663)

Dero obtusa d'Udekem, 1855 (ref. ID; 1257, 1663, 1923, 1928, 3692, 6913, 7854) reported author and year? (ref. ID; 5939)

Descriptions

Branchial fossa without long palps. Asexual reproduction by budding. Ventral setae of II to V sharply differentiated from those of other segments. With two pairs of gills. (ref. ID; 1663)

Normally 3 pairs of gills; distal bifurcations of dorsal needle setae approximately equal. (ref. ID; 1923)

Dero raviensis (Stephenson, 1914) emend. Grimm, 1985 (ref. ID; 6554)

Synonym

Nais raviensis Stephenson, 1914 (ref. ID; 6554)

Descriptions

Dorsal chaetal from VI, 1 short hair, 107-110 µm, and 1 or 2 needles, 35 µm, per bundle, needles with short diverging teeth and a distal nodulus. Ventral chaetae 3 or 4 per bundle, those of II-V much longer and thinner than the rest (70-80 vs. 35-42 µm) with a distal nodulus and the upper tooth longer than the lower, posterior chaetae with a distal nodulus and the upper tooth thinner than and only slightly shorter than the lower. Stomach dilation inconspicuous. (ref. ID; 6554)

Remarks

This species was reported from the Neotropical fauna in Surinam by Harman (1974). His specimens had anterior ventral chaetae of the more usual size of 70-80 µm, the other chaetal dimensions being similar to those quoted above. The species is abundant in Surinam and has probably been overlooked elsewhere in the Neotropical region. Grimm (1985) recognized this as a species of Dero. Our specimen is incomplete. (ref. ID; 6554)

New record

Peru: Yanayako River, Amazon basin above Iquitos, June, 1985, coll. R.O. Brinkhurst, 1 specimen. (ref. ID; 6554)

Dero vagus Leidy, 1880 (ref. ID; 6554) reported year? (ref. ID; 1663) reported author and year? (ref. ID; 5939)

Descriptions

Branchial fossa with two long palps. Dorsal setae beginning on VI. (ref. ID; 1663)

Remarks

This North American species can now be reported for Peru. The chaetal sizes for anterior and posterior ventrals, needles, and hairs are 80, 62-65, 91-100, and 133-148 µm, respectively. The needles are characteristically broadly palmate. The vental chaetae are shorter than in material from Texas (Harman 1973). The presence of a stomach, coelomocytes, and the chaetal lengths distinguish this species from its congeners ah are more usually found in South America. (ref. ID; 6554)

New record

Peru: Lake Yarinacocha and Rio Curanja, Depto. Loreto, 1965-1966, coll. J. O'Neill, A.L. Gardner, 2 specimens, W.J. Harman collection. (ref. ID; 6554)