Several ichthyolith subtypes and similar (cf.) subtypes from both the Tofino Basin and deep-sea cores have overlapping occurrences. They fit into intervals spanning the Cretaceous to lower Paleogene, the Eocene to lower Miocene (Table 3), and the upper Oligocene to Pliocene (Table 4).

Eight ichthyolith subtypes have a deep-sea core and Tofino Basin overlap occurrence in the Oligocene (Table 3). Most range from the Paleocene/lower Eocene to the lower Miocene. The top of the ranges of kite-shaped longitudinal line Doyle et al. 1974 and triangle transverse line across Doyle et al. 1974 occur in the Oligocene. Most of the eight subtypes are interpreted to have been deposited approximately in situ within bathyal environment strata.

Kite-shaped longitudinal line and pointed and skirted Doyle et al. 1978 are common in Upper Cretaceous deep-sea cores. Tofino Basin Superorder Squalomorphii (squaloid) forms and pointed and skirted Doyle et al. 1978 are common to abundant, reworked, and deposited in Oligocene strata. In the deep-sea cores, squaloid-like forms are present (e.g., curved fibrous triangle Tway et al. 1985 and fibrous triangle convex margins Tway et al. 1985). Pointed and skirted are rare in deep-sea Oligocene strata. This difference in ichthyolith distribution and abundance could indicate that the Tofino Basin has a proximal and more favourable environment for these fishes. However, more likely, the sedimentary conditions and active tectonic environment of the Tofino Basin resulted in concentration of older ichthyoliths or mixed faunas into younger sediments. Cameron 1980 commented that the Hesquiat Formation Oligocene Turrilina alsatica and Bulimina cf. alsatica foraminifer zones contain a large number of reworked older (Cretaceous and Jurassic) foraminifer species.

Five ichthyolith subtypes have a deep-sea core and Tofino Basin overlap occurrence in the upper Oligocene through Pliocene (Table 4). Narrow curved triangle Doyle et al. 1974 is an indicator of the upper Oligocene and lower Miocene in deep-sea strata and is in agreement with a similar subtype cf. narrow curved triangle occurring in upper Oligocene to middle Miocene fine-grained deeper water slope to bathyal strata above the Eocene volcanics of the Zeus D-14 (4620-7600 ft) and Prometheus H-68 (5550-60 ft) wells. Although rare in the Tofino Basin Cygnet J-100, Apollo J-14, and Prometheus H-68 wells, cf. long triangle stepped margin Doyle et al. 1974 shows a similar occurrence to long triangle stepped margin Doyle et al. 1974 found in upper Miocene and Pliocene deep-sea strata.

Sixteen new Tofino Basin subtypes are described and illustrated in this catalogue. Most of these new subtypes are cone teeth (11 subtypes) and triangular teeth with canals (3 subtypes). There is one triangular flanged tooth and one elasmobranch dermal denticle new subtype. The majority of the new cone tooth subtypes and specimens are mainly in Miocene Shell Canada well sample intervals. Only one new cone tooth subtype (dome-top triangle bowed inline) is from marine outcrop samples on the Hesquiat Peninsula (upper Eocene-Oligocene). The three new teeth with canals subtypes are in upper Eocene and Oligocene intervals, two are triangular with flanged margins and one is a curved triangular cone tooth. The new elasmobranch dermal denticle subtype (three peaks forked median ridge) occurs in Oligocene strata (possibly reworked from the Cretaceous through Eocene), and triangle chisel-top is a rare but distinctive Miocene ichthyolith that occurs in the Shell Canada well samples.

Ichthyoliths near the boundary of the Turrilina alsatica and Bulimina cf. alsatica foraminifer zones (Cameron 1980) are common in three samples (BC-74 spot checks 7, 8, and 15) and fewer numbers in other stratigraphically close samples. While their concentrated occurrence in these samples may have resulted in a turbidite or lag deposit, it may also represent faunas that associated together or were even represented by the same species (e.g., elasmobranchs/sharks can have several different types of teeth and dermal denticles on the same fish).

Most of the Superorder Squalomorphii teeth (~60 specimens) occur at this level and forms share many similar characteristics such as overall shape, inline type, a broad lateral flanged occlusal crest/margin, and the outline texture. All are tooth fragments. Teeth with a lobed tooth base and one long flanged convex tooth margin that basally curves inwards to a point are probably of the Family Squalidae. Specimens that do not have the above features and instead have shorter flanged margins where one or both may basally curve upwards (to form part of the next tooth file of a set) are probably of the Family Hexanchidae.

Also occurring in these samples is centrally inflated triangle with canals new subtype (37 specimens). It shares many of the Tofino Basin Squalomorphii tooth features but has inline canals and generally is not as robust. Elasmobranch dermal denticles pointed and skirted Doyle et al. 1978 (26 specimens), kite-shaped longitudinal line Doyle et al. 1974 (17 specimens), and three peaks forked median ridge new subtype (10 specimens) also commonly occur at this level. These dermal denticles, especially pointed and skirted, show many similarities in shape, pedicle, and crown ridges to dermal denticles of Centrophorus granulosus (Bloch and Schneider 1801) (e.g., Reif 1985, plate 5), a Holocene deep water gulper shark of the Family Squalidae known from the Mediterranean. The relationship of this Holocene shark to the older ichthyoliths from the Tofino Basin cannot be determined from this study but dermal denticle morphological characteristics do suggest some Tofino Basin faunal representatives from the Family Squalidae.

Angled cone and bulbous base, a distinctive new subtype, occurs in many of the Shell Canada well Miocene and Pliocene samples. Its bulbous and elongate character may indicate a pharyngeal tooth form. The co-occurring new subtype narrow tall triangle inflated inline apex and narrow tall triangle irregular threaded inline are closest in overall shape and type of inline to angled cone and bulbous base, mainly differ by being narrower and taller and having a less bulbous tooth base, and may indicate species heterodonty. Other co-occurring subtypes such as cf. narrow curved triangle Doyle et al. 1974, and curved triangle parallel-sided inline and curved triangle wide inline (new subtypes) are common, and probably represent different faunas sharing a similar environment as angled cone and bulbous base.