NAME Inapertisporites elongatus
AGE Late Cretaceous & Middle Eocene.   AGE span: 88.6...40.4 mya
K&J CLASSIFICATION (2000) Fungi Imperfecti, Amerosporae.
FIGURE(S)
Image of
Pl.1fig.8.jpg
FIGURE REFERENCE Rouse GE. 1962. Plant microfossils from the Burrard Formation of western British Columbia; Micropaleontology, v. 8, p. 187-218.
SPECIES, AUTHORITY I. elongatus (Rouse) Kalgutkar & Jansonius 2000
LOCATION Burrard Formation at Terminal Dock, British Columbia, Canada.
ORIG DESCRIPTION* Spores small, elongate elliptical in outline, with a thick wall (ca. 3 µm). The spores are deep melanin brown and have at least one very small pit on the wall; this is sometimes central (pl. 5, fig. 14) and sometimes terminal (pl. 5, fig. 15). Size-range 6-15 µm.

EMENDED DESCRIPTION (Elsik 1990a, p. 149): Aseptate, psilate fungal spores ca. 8 x 13 µm overall. Outline elliptical, ends broadly rounded, somewhat subrectangular overall. The subangularity at the ends of the spore is most noticeable at or just past the ends of the furrow. The furrow evidently reaches both ends of the spore. The holotype specimen is apparently oriented in side view; overlapping edges of the furrow or equivalent fold are seen on the left side of the illustration.
COMMENTS* (Rouse): There are many spores of this species in the Terminal Dock preparations. They are variable in size but all obviously fungal. It is not known whether one or many natural taxa are represented. However, there was a strong fungal element in the pre-sediment swamps in that area.

(Elsik): Hypoxylonites elongatioides is similar but there is a more smoothly rounded outline over the ends of those spores. Rouse noted the presence of spores of variable sizes in the material he was examining. The species here is restricted to those spores of a size most like the holotype, and with a furrow.
PUBLICATION REFERENCE Rouse GE. 1962. Plant microfossils from the Burrard Formation of western British Columbia; Micropaleontology, v. 8, p. 187-218.

Elsik WC. 1990. Hypoxylonites and Spirotremesporites, form genera for Eocene to Pleistocene fungal spores bearing a single furrow; Palaeontographica, Abt. B, v. 216, p.137-169.
K&J REMARKS From the qualifications in his emended description ("evidently," "apparently") it appears that Elsik did not examine the type specimen directly, but gave his interpretation of Rouse's photograph. Kalgutkar and Jansonius (2000) also scrutinized that photograph, but come to a different conclusion. Kalgutkar and Jansonius (2000) think (as apparently did Elsik, who ignored this feature) that the short split in the upper part of the specimen, punctuated by two "pores," is preservational damage of this particular specimen. Elsik points to the left margin of the spore, where he appeared to have seen overlapping parts of spore wall, suggesting the presence of a furrow. In Kalgutkar and Jansonius's (2000) interpretation, this left margin is curved (up or down) out of the focal plane, causing the outline of the spore to deviate excentrically, and simultaneously to become more blurred.

However, Kalgutkar and Jansonius (2000) were not convinced by Elsik that this feature must represent a furrow (or a fold, or slit). Also, none of the species assigned to Hypoxylonites possess as thick a spore wall as occurs in Inapertisporites elongatus. Therefore, Kalgutkar and Jansonius (2000) have not accepted Elsik's transfer of this species to Hypoxilonites.

Rouse gave the spore size as 6-15 µm in his text. On each plate he gave a scale, and by this scale the length of the type specimen is 25 µm. Yet, the plates are also stated as illustrating the spores at 500x magnification, which would give a length of 28 µm for the type. Kalgutkar and Jansonius (2000) have no ready explanation for these discrepancies in measurements.
TYPE
ALL NAMES (Including synonyms) Inapertisporites elongatus Rouse 1962, p. 208, pl. 5, fig. 14.
Hypoxylonites elongatus (Rouse) Elsik 1990a, p. 149.; Inapertisporites elongatus
SERIAL NUMBER 781
PUBLIC COMMENTS
 *For source, see Publication Reference.