Genus Adelosina


Adelosina d’Orbigny 1829


Luczkowska (1972) emended d’Orbigny’s original description of the genus Adelosina with the following diagnosis: Test with quinqueloculine internal structure in microspheric generation; the megalospheric generation with cornuspirine initial part, composed of large proloculus and tubular second chamber encircling the proloculus, third chamber placed in plane of coiling 90o apart, next chamber in plant of coiling 130-160o apart; the juvenile stage of mega II generation in the characteristic lenticular form, which may grow into planispirally arranged, slightly evolute forms; 3, 4, or 5 chambers visible from the outside chambers with floor; aperture circular at end of the neck, with a short bifid tooth.


Luczkowska (1927) differentiated this genus from Quinqueloculina by a) the presence of the cornuspiroid second chamber with neck that encircles the proloculus in the juvenile and forming the characteristic lenticular test, and b) the tendency of the last chamber to uncoil in mature specimens. One of the species transferred by Luczkowska (1927) to Adelosina is Quinqueloculine longirostra.



Adelosina longirostra (d’Orbigny, 1826)


Quniqueloculina laevigata d’Orbigny, 1839, tome 2, pt. 2, p. 143, pl. 3, figs. 31-33; Cushman 1929, U.S. National Museum Bulletin 104, part 6, p. 30, pl. 4, Figs. 3a-c; Cushman 1935, p. 14, pl. 2, figs. 13-15.

Quinqueloculina longirostra d’Orbigny, 1926, series 1, tome 7, p. 303; d’Orbigny, 1846, p. 291; Parker, Jones and Brady, 1871, pl. 8, fig. 8; McGann, 2007, p. 64, pl.9, fig. GG..
Adelosina longirostra (d’Orbigny, 1826) Luczkowska, 1927, p. 366, 354-55.


Remarks: D’Orbigny did not give a description of Quinqueloculina longirostra when he first named the species, and the first illustration was by Parker, Jones and Brady, 1871.


Distribution: Rare occurrences of A. longirostra have been recorded along the length of Puget Sound.

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