Named for Michael A. Rich (UWBM) who has produced numerous research photographs for the paleontology team at the University of Washington, including those of the new species described here.

UWBMVP 128914 (Fig. 2A, B), consisting of one otolith, 248 body scales, three vertebrae, some teeth and other bones that are all assumed to be from one individual fish.

Sekiu River (UWBMVP loc. C4510), Makah Formation, Lower Oligocene. The fish remains were contained in a small piece of weathered concretion, found as float, at extreme low tide on the beach terrace west of the mouth of the Sekiu River, NE corner of Sec. 8, T. 32 N., R. 13 W., Clallam County, Washington, U.S.A. GPS: 48.292591°N, 124.400048°W, collected by J. L. Goedert, 18 April 2025.

Otolith: Otolith length to otolith height = 1.4. Low dorsal rim, undulating, highest behind middle of otolith; ventral rim deep, deepest anterior of middle below ostium. Sulcus wide, supramedian positioned, with large, about equally sized and symmetric, elevated, narrowly placed colliculi. No pseudocolliculum in narrow collum. Ventral furrow relatively distinct.

Scales: Cycloid-spinoid; spines, robust, not aligned, one third to one half of scale length, angled at 80 to 90° relative to scale surface. Radii absent; no reticulate structure on scales.

Otolith, Fig. 2A, B. The otolith is large, 14.5 mm in length and with an overall oval shape. The otolith has been replaced by silica, like all the associated remains found in the concretion. The otolith is slightly encrusted with silica, which results in an uneven otolith surface but leaving all pertinent diagnostically valuable characters discernable. The ratio of otolith length to height is 1.4 and otolith height to thickness 3.3. The dorsal rim is relatively low, broadly undulating and shows a broad depression at about its middle and a broadly rounded postdorsal high. The anterior and posterior tips of the otolith are moderately pointed and positioned slightly supramedian. Both tips show a flattened dorsal margin at the beginning of the dorsal rim. The ventral rim is relatively regularly curved, deepest in front of its middle below the center of the ostium on the inner face. The postventral section of the ventral rim is almost straight, ascending at an angle of about 20° while the preventral section is more steeply inclined at about 45°. All rims are smooth.

The inner face is nearly flat and shows a wide, supramedian positioned sulcus. The sulcus narrows toward anterior and posterior with a fading opening to the otolith rims. The colliculi are very large, wide, oval, reach close to the otolith rims anteriorly and posteriorly, and are slightly elevated. They are closely positioned, leaving little space for the narrow collum. The collum shows a deep incision from the ventral sulcus margin without pseudocolliculum. The ratio ostial colliculum length to caudal colliculum length is 1.05, the ratio ostial colliculum height to caudal colliculum height is 1.35, and the length to height ratios are 1.75 for the ostial colliculum and 2.15 for the caudal colliculum. A dorsal depression is not discernable. The ventral furrow is relatively distinct and located relatively distant from the ventral rim of the otolith. The outer face is slightly bulged but overall flat and smooth.

Scales, Fig. 3. Scales are of the cycloid-spinoid type (Bräger and Moritz 2016) with a circular to polygonal shape. The focus is in central position. Circuli are distinct and continuous throughout all fields. Radii are absent. Reticulate structure on any scale area absent. In typical body scales, as expected on the flanks, the anterior field is strongly convex with a rounded apex and smooth margin. Lateral fields are convex to flattened with smooth margin. The posterior field is rounded with a smooth margin and bears prominent spines. These spines are very strong, robust, moderately long to long, and not aligned in strict rows.

In typical body scales, the longest spines are about one third to one half of the scale length. In some smaller peripheral scales the spine length may even clearly surpass scale length. Spines are straight or only slightly curved and usually angled at 80 to 90 degrees relative to the scale surface.

Otoliths, Fig. 2. The large size of the otolith, its robust shape and the sulcus harboring two equally sized, closely spaced large colliculi and the lack of a pseudocolliculum in the collum characterize Coryphaenoides richi as pertaining to the genus Coryphaenoides. Coryphaenoides is the second most species-rich genus of the Macrouridae after Coelorinchus, of which the otoliths are characterized by the presence of a pseudocolliculum in the ventrally expanded collum and colliculi where the caudal colliculum is distinctly longer than the ostial one. Within Coryphaenoides, several variations of otolith patterns are observed. The pattern that resembles closest is depicted here with extant examples: Coryphaenoides carminifer (Garman, 1899) from the tropical East-Pacific (Fig. 2E, F), Coryphaenoides marshalli Iwamoto, 1970 from off southern tropical West Africa (Fig. 2C, D), Coryphaenoides rupestris Gunnerus, 1765 from off Norway (Fig. 2G, H) and Coryphaenoides woodmasoni (Alcock, 1890) from the Laccadive Sea (Fig. 2I, J).

The otolith of C. richi differs from the figured otoliths of extant taxa in the more pointed anterior tip and, except for C. carminifer, in the deepest point of the ventralrim positioned distinctly anterior of its middle, while this section is flat in the other species shown in Fig. 2. The colliculi are larger in C. richi than in otoliths of most extant species, the closest resembling being those of C. marshalli and C. rupestris.

Fossil Coryphaenoides otoliths have been regularly reported in the fossil record from Miocene and younger deep-water sediments (see Nolf 2013; Schwarzhans and Radwańska 2025). Earlier records from the Oligocene are few (Nolf 2013) and require revision as they could potentially represent extinct macrourid genera. An articulated skeleton with otoliths in situ was described as Coryphaenoides karaginensis from upper Oligocene rocks of Kamchatka by Gretshina (1973). This otolith represents a different lineage of the genus characterized by a wide collum and relatively small colliculi. Brzobohatý and Bubík (2019) figured an otolith from the lower Oligocene of the Czech Republic as representing the extant Coryphaenoides aff. guentheri (Vaillant, 1888). This specimen undoubtedly pertains to the genus Coryphaenoides, it again represents a different lineage characterized by relatively small, narrow spaced colliculi terminating far from the anterior and posterior tips of the otolith but certainly does not represent an extant species. No records of Coryphaenoides otoliths are known from Eocene strata, although the earliest macrourids have been reported from the Paleocene (Schwarzhans et al. 2021).

Scales, Figs 3, 4. The observed scales with the characteristic spines likely originate from a single species; the obvious differences are easily explained by size of the specimens and variability depending on body position within a species (e.g., Bräger and Moritz 2016). A few selected scales were sampled from museum material of the ichthyological collection of the Zoological Museum Hamburg (ZMH).

Only a portion of the fossil scales represent typical scales, as usual in studies on recent species, where standard scales are commonly taken from the anterior dorsal part of the flank. Many of the smaller scales, often with very long spines in comparison to the actual scale length may originate, e.g., from the head region or the bases of the fins. The whole variability in the studied material fits into the variability found in a single species, even a single specimen. Otoliths and scales in combination identified the fossils as a grenadier fish of the genus Coryphaenoides, Macrouridae. The scales described here from Coryphaenoides richi clearly differ from all macrourid scales, fossil or extant, so far known by the combination of all characters.

Few taxa, like in the related bathygadids Gadomus and Bathygadus, show a reticulate pattern on the scale surface; such a pattern is absent in the studied fossil scales. The spines present in C. richi are strong, much stronger than in e.g., Coryphaenoides asper Günther, 1877, C. guentheri (Vaillant, 1888) or C. soyoae Nakayama & Endo, 2016 (see Cohen et al. 1990; Nakayama 2020), but not broad with a broader base as in e.g., Coryphaenoides subserrulatus Makushok, 1976 (Fig. 4C) or many Coelorinchus species (Okamura 1970; Cohen et al. 1990). The spines are furthermore long, about as long as in Coryphaenoides mexicanus (Parr, 1946). All spines have a single tip, not tridentate as e.g., in Coryphaenoides marshalli and C. delsolari Chirichigno & Iwamoto, 1977 (see Cohen et al. 1990). The spines per scale are numerous, more densely set than in the majority of species in the genus, but not as densely set as e.g., in Coryphaenoides serrulatus Günther, 1878 and C. subserrulatus (see Cohen et al. 1990; Fig. 4C).

The scale spines of C. richi do not originate from secondary ridges, but independently of the surface (cf. Okamura 1970). Even if the spines are not bound on ridges, they are in most taxa more or less arranged in rows (Fig. 4B–D), which may be parallel, sub-parallel or radial (also called divergent), sometimes with the middle row being enlarged. Yet, probably the most striking character of C. richi scales is that no such arrangement can be seen. This characteristic also serves well to distinguish C. richi from the various macrourid taxa from Cenozoic rocks of the Pacific Coast of North America described by David (1956). A similar unordered pattern can be found in the recent Coryphaenoides rudis Günther, 1878 (see Cohen et al. 1990: as C. macrocephalus, Nakayama 2020, Fig. 4A). Spines of that species are also similar in amount and size. But the orientation of the spines clearly differs; while the spines in lateral view are oriented relatively flat in C. rudis (Fig. 4A), they point straight away from the scale plane in the C. richi.

Whether the peculiar spine pattern of C. richi is a specific adaptation or rather presents a primitive condition is difficult to state. Following morphology-based phylogenies (Okamura 1970: fig. 10; Endo 2002) the primitive scale pattern in Coryphaenoides already showed spines ordered in rows. Following this view the observed pattern in C. richi has to be interpreted as derived. More recent phylogenetic studies do not yet comprise enough species of the high macrouroid diversity to allow for a character reconstruction of the scale patterns in grenadier fishes (e.g. Morita 1999; Gaither et al. 2016).