1 Supplementary information 2 3 Dental diversity in early chondrichthyans
4 and the multiple origins of shedding teeth
5 6 Dearden and Giles 7 8 9 This PDF file includes: 10 Supplementary figures 1-5 11 Supplementary text 12 Supplementary references 13 Links to supplementary data 14 15 16 Supplementary Figure 1. Taemasacanthus erroli left lower jaw NHMUK PV 17 P33706 in (a) medial; (b) dorsal; (c) lateral; (d) ventral; (e) posterior; and (f) 18 dorsal and (g) dorso-medial views with tooth growth series coloured. Colours: 19 blue, gnathal plate; grey, Meckel’s cartilage. 20 21 Supplementary Figure 2. Atopacanthus sp. right lower or left upper gnathal 22 plate NHMUK PV P.10978 in (a) medial; (b) dorsal;, (c) lateral; (d) ventral; and 23 (e) dorso-medial view with tooth growth series coloured. Colours: blue, 24 gnathal plate. 25 26 Supplementary Figure 3. Ischnacanthus sp. left lower jaw NHMUK PV 27 P.40124 (a,b) in lateral view superimposed on digital mould of matrix surface 28 with Meckel’s cartilage removed in (b); (c) in lateral view; and (d) in medial 29 view. Colours: blue, gnathal plate; grey, Meckel’s cartilage. 30 Supplementary Figure 4. Acanthodopsis sp. right lower jaw NHMUK PV 31 P.10383 in (a,b) lateral view with (b) mandibular splint removed; (c) medial 32 view; (d) dorsal view; (e) antero-medial view, and (f) posterior view. Colours: 33 blue, teeth; grey, Meckel’s cartilage; green, mandibular splint. 34 35 Supplementary Figure 5. Acanthodes sp. Left and right lower jaws in 36 NHMUK PV P.8065 (a) viewed in the matrix, in dorsal view; (b) superimposed 37 on the digital mould of the matrix’s surface, in ventral view; and (c,d) the left 38 lower jaw isolated in (c) medial, and (d) lateral view. Colours: grey, 39 endoskeleton; green, dermal skeleton; white, matrix/mould. 40
41 42
43 Supplementary text
44 Section 1 – Full description of jaw elements
45 Taemasacanthus
46 Taemasacanthus erroli is known from eight isolated jaws from the Emsian
47 (Lower Devonian) Murrumbidgee Group in New South Wales, Australia (1).
48 Other species, also based on isolated jaw bones, have been assigned to the
49 genus (2,3), but no articulated animals are known. Taemasacanthus is
50 understood to be an ischnacanthid on the basis of its similarity to well-known
51 members of that grade. NHM UK PV P.33706, described here, is a lower right
52 jaw, and is comprised of two main parts: a dermal gnathal plate and the
53 articular ossification of Meckel’s cartilage. The external morphology of this
54 jawbone in Taemasacanthus is fully described by Long (1986), but is briefly
55 redescribed here to contextualise our new information.
56 The gnathal plate is approximately half the full depth of the jaw, and is
57 sinusoidal in dorsal view (Figs. 1a,b,S1). A circular ridge, which Long (1986)
58 suggests might be for a labial cartilage, is present on the lateral surface
59 approximately ¼ of the way along its length (Fig. S1c). Anterior to this, the
60 gnathal plate curves medially to follow the outline of the jaw, with the lateral
61 tooth row positioned on its dorso-lateral surface. Posteriorly, the gnathal plate
62 curves laterally and broadens to wrap around the articular (Fig. S1b). The
63 lateral expansion is larger than the medial expansion, and both are rounded
64 posteriorly. Ventrally, a groove formed by the posterior confluence of these
65 two processes runs underneath the entire length of the gnathal plate, and 66 would have overlain Meckel’s cartilage (Fig. S1d). The greatest part of the
67 gnathal is approximately trapezoid in cross section, and bears three rows of
68 teeth. Histologically this comprises heavily vascularised dermal bone, similar
69 to that observed in thin sections of other ischnacanthid jaw elements (4–6),
70 with a relatively thin layer of less vascularised bone around the plate margins.
71 The vascularisation comprises an interlinked network of tubules, which are
72 strongly polarised along the anteroposterior length of the element (Fig. 1c). In
73 transverse section these are near-horizontal, running the width of the element,
74 and are interlinked. The circular ridge is formed of avascular bone, but is
75 otherwise a similar tissue to that forming the outer margin of the gnathal plate.
76 The dermal bone is broken anteriorly, exposing the histology and shearing
77 through a tooth.
78 Three rows of teeth are present in Taemasacanthus, all starting approximately
79 at the level of the mesial ridge: a lateral row, medial row, and lingual row
80 (Figs. 1, S1a,f,g). The mesial ridge is formed by the dorsal corner of the
81 underlying gnathal plate, and bears a disorganised row of irregular cusps.
82 These cusps are continuous with the underlying dermal bone, and only the
83 more posterior few are vascularised. The cusps extend along roughly the
84 posterior half of the mesial ridge – anteriorly the ridge is smooth. The lateral
85 tooth row comprises around twelve cusps, mounted on the dorso-lateral face
86 of the gnathal plate. Posteriorly these are approximately the size as the
87 mesial ridge cusps, but they become progressively larger anteriorly. This tooth
88 row follows the outside of the gnathal plate, and teeth are joined by a ridge
89 which, along with the teeth themselves, is laterally continuous with the plate’s
90 outer surface. The lingual side of each cusp is rounded, and ornamented with 91 a number of ridges, which become progressively more tuberculated on
92 anterior cusps. The lingual row comprises ten cusps which become
93 progressively larger anteriorly, and which curve antero-medially along the
94 dorso-lingual surface of the underlying dermal plate. Cusps are similar in
95 shape and ornament to those of the lateral row, but without the outer ridge,
96 instead being completely surrounded by the ridged ornament. The histology of
97 the lateral and lingual tooth rows is similar, comprising a vascular internal
98 tissue, seemingly without a continuous enameloid covering (Fig. 1c). In both
99 rows, teeth are added anteriorly, with anterior cusps overlying posterior ones.
100 In what is probably a pathology, the eighth cusp of the lingual row is
101 incomplete, and is either damaged or its growth appears to have been
102 aborted (Fig. 1a)). The ninth cusp in the row has instead grown over the
103 incomplete eighth as well as the tenth cusp. This is in fact the youngest cusp
104 in the entire row, and is oriented notably more medially.
105 Only the posteriormost portion of the Meckel’s cartilage, the articular
106 ossification, is preserved (Figs. 1, S1). It is formed from a sheath of
107 perichondral tissue, and would have been filled with cartilage in life. Some
108 spongy texture is apparent on the interior surface of the perichondral bone. A
109 shallow groove on the posterior surface does not appear to continue ventrally,
110 making it unlikely to have accommodated a mandibular splint (as suggested
111 by Long 1986). Articulation with the palatoquadrate appear to be via a an
112 open, oval, fossa (Long 1986) (Fig. S1b). The tissue forming this is however
113 notably ill-formed, and appears to lack a solid perichondral covering, meaning
114 that it could well, as Burrow (2004) suggests, be a typical ischnacanthid 115 process that has lost its tip. An additional ventral fragment of the articular (as
116 figured in Long 1986) has become detached from the rest of the ossification.
117 Atopacanthus
118 The genus Atopacanthus is known throughout the Middle-Upper Devonian (7).
119 The type species, Atopacanthus dentatus, is known from several jaws from
120 near Hamburg, New York (8,9). Articulated fossils of Atopacanthus sp. from
121 the Upper Devonian are also known (10), their attribution to this genus is
122 questionable (11). The specimen described here, NHMUK PV P.10978, was
123 collected from Elgin, Scotland, in making it Middle Devonian in age. It was
124 originally labelled as possibly dipnoan, before later being referred to
125 Atopacanthus, and its morphology conforms with that of other specimens
126 described as Atopacanthus.
127 This specimen comprises a dermal jawbone (Figs. 1d-f, S2). It is not
128 associated with any endoskeletal material, making it impossible to tell whether
129 it is from a right lower jaw or upper left jaw. For ease of comparison with other
130 specimens, we describe its morphology as if it were a lower jaw element. As
131 in Taemasacanthus, the gnathal plate is robust, and likely occupied most of
132 the full depth of the jaw. It is trapezoid in cross-section, but flatter and taller
133 proportionate to its length than in Taemasacanthus, and is slightly medially
134 convex. The element appears to be broken both anteriorly and posteriorly,
135 with internal histology visible at both ends. The anterior fifth of the element is
136 toothless and tapers slightly. A narrow, shallow groove to accommodate the
137 mandibular cartilage runs along the ventral surface of the element (Fig. S2d).
138 Internally the histology is similar to Taemasacanthus, being heavily 139 vascularised antero-posteriorly oriented tubules (Fig. 1f). However, the
140 lamination of this vascularisation is more pronounced, and they are clearly
141 oriented in an antero-dorsal direction. Towards the surface of the element
142 vascularisation is less dense, and not polarised. On the lingual face of the
143 element is a thin lingual plate. This is still heavily vascularised, but tubes are
144 instead polarised across the dorso-lingual surface of the main dental plate.
145 As in Taemasacanthus, lateral, mesial and lingual tooth rows are borne on the
146 dorsal surface of the gnathal plate (Figs. 1,S2). The medial ridge bears two
147 disorganised rows of cusps along its anterior half, with the posterior half being
148 smooth. These cusps are avascular, and are histologically continuous with the
149 medial ridge. The lateral tooth row comprises eight cusps, which become
150 progressively larger anteriorly. As in Taemasacanthus, they are joined by a
151 ridge, making their lateral surfaces continuous with the outside of the element.
152 Their lingual surfaces are rounded and ornamented with untuberculated
153 ridges. The inner tooth row comprises ten main cusps, which curve medially
154 across the element. Two additional small (but histologically similar) cusps are
155 present near the posterior margin of the gnathal plate, ventral to the main
156 lingual tooth row. This tooth row is lies on top of a lingual plate, which is
157 apposited onto the lingual surface of the main gnathal plate. As in the lateral
158 row and in Taemasacanthus, cusps become larger anteriorly, and are
159 ornamented with ridges. The histology of the teeth of the lateral and lingual
160 rows comprises a vascular base topped with an avascular cap (Fig. 1f). Teeth
161 in both the lateral and lingual rows were added anteriorly, with anterior cusps
162 partly overlying their posterior fellows.
163 Ischnacanthus 164 Ischnacanthus is the best known ischnacanthid ‘acanthodian’, represented by
165 numerous articulated specimens of Lochkovian (Lower Devonian) age from
166 the Midland Valley in Scotland (4). The material described here (NHMUK PV
167 P.40124) comprises an isolated left lower jaw from the Lower Devonian
168 (Lochkovian) Midland Valley in Tealing, Forfarshire (12). It is fairly complete,
169 but parts of the dorsal and anterior margins have been lost to the counterpart,
170 and the whole jaw is laterally flattened. It comprises a gnathal and a
171 Meckelian cartilage.
172 Only the anterior part of the dermal jaw bone is preserved in the part (Fig.
173 S3). The mould of the posterior part is visible in outline. A lateral tooth row
174 and a medial ridge are visible. The lateral tooth row preserves four cusps,
175 which are linked by a cuspidate ridge. Relative size is difficult to determine
176 due to the mode of preservation, but the anteriormost cusp is the largest.
177 Although the ventralmost parts of the dermal ossification are missing, is clear
178 that the teeth were histologically distinct from the underlying plate. The tissue
179 seems similar to Taemasacanthus and Atopacanthus, which a vascularised
180 base and an avascular crown. Teeth appear to have been added anteriorly.
181 The Meckel’s cartilage is preserved as a single ossification (Fig. S3). It is
182 curved posteriorly and tapers anteriorly. The gnathal plate is borne on its
183 dorso-lingual surface. A laterally-directed articular condyle is present at the
184 posterior extent, and A shallow groove extends ventral to the condyleThe
185 majority of the Meckel’s cartilage comprises a structureless tissue, which is
186 likely to be globular calcified cartilage. Parts of it, particularly at its ventral,
187 anterior, and posterior extents, preserve what may be perichondral bone or
188 calcified cartilage at the surface (4). A thickened ridge along the 189 posteroventral and posterior margin is continuous with the rest of the
190 cartilage, but externally gives the appearance of a separate ossification. In
191 section this is closely comparable to the the so called “mandibular bone”
192 which Ørvig (1967) described in Xylacanthus, and is probably responsible for
193 accounts of mandibular splints in ischnacanthids.
194 Acanthodopsis
195 Acanthodopsis is known from the Carboniferous of the UK and Australia. In
196 the past Acanthodopsis has been considered an ischnacanthid on the basis of
197 its “dentigerous jaw bones”; however in terms of its skeletal anatomy it is far
198 more similar to acanthodids, as recognised by Burrow (2004b). The material
199 described here, NHMUK PV P.10382 from the Northumberland Coal
200 Measures, comprises a laterally flattened lower right jaw, consisting of a
201 Meckel’s cartilage with teeth and a mandibular splint.
202 The Meckel’s cartilage is long and thin, and similar in shape to that of
203 Acanthodes (Figs. 1g-i). The jaw articulation is identical to that of Acanthodes,
204 with a marked preglenoid process and a lateral articular fossa (13). A slight
205 groove is present on the posterior margin of the cartilage posterior to the
206 articulation. The Meckel’s cartilage tapers anteriorly, terminating in a small,
207 cup-shaped anterior symphyseal structure (Figs. 1h, S4e). A similar structure
208 is present in Acanthodes (see above) as well as in Halimacanthodes (14).
209 This is seemingly absent in Ischnacanthus (4) as well as in more crownwards
210 taxa such as Gladbachus, Pucapampella, and Gogoselachus (15–17), and its
211 presence may be a character grouping Acanthodes and related taxa. The
212 Meckel’s cartilage is formed from a shell of perichondral bone and is internally 213 unmineralized (Fig. 1j), although some internal mineralisation appears to be
214 present in the jaw articulation. Unlike Acanthodes, it is perichondrally
215 mineralised along its entire length, rather than in separate articular and
216 mentomandibular sections (Fig. 1g-i).
217 A row of ten separate teeth are borne along the dorsal margin of the cartilage
218 (Figs. 1,S4). The fifth tooth in the row is the largest, with cusps decreasing in
219 size anteriorly and posteriorly. Each tooth is triangular in shape and curved
220 labially. The lateral surface is smooth, while the inner surface is striated from
221 tip to base. Histologically they are separate from the underlying Meckel’s
222 cartilage, and formed largely from a vascular tissue, with avascular crowns
223 (Fig. 1i,j). The direction of growth is difficult to infer, but the largest tooth
224 appears to be overlapped by the anterior and posterior teeth, making it the
225 oldest.
226 The mandibular splint is positioned along the ventral part of the Meckelian
227 element (Figs. 1,S4). It is unornamented, and is ellipsoid in cross-section. It is
228 positioned in a groove on the lateral face of the cartilage, although this groove
229 was likely originally much shallower (as in Acanthodes), and its depth has
230 been exaggerated by lateral flattening of the specimen. The posterior third of
231 the splint is comparatively flat and slightly dorsally convex, giving it an overall
232 slightly sigmoid shape. About halfway along its length its cross-section
233 becomes more rounded and it expands slightly before tapering anteriorly. The
234 tissue forming it is fairly solid, and pierced by longitudinal vascularisations.
235 Burrow (7) reported that the mandibular splint in Acanthodopsis was formed
236 from cartilage and (presumably endoskeletal) bone based on thin sections.
237 However, on the basis of its dissimilarity to both the perichondral bone and 238 cartilage of the Meckelian ossification (Fig. 1i.j)), as well as the
239 vascularisation, we consider the splint to be a dermal bone.
240 Acanthodes
241 Acanthodes is a relatively late occurring genus of ‘acanthodian’ found from
242 the Missisippian (Carboniferous) into the Lower Permian (18). It is the only
243 genus of ‘acanthodian’-grade animal known from extensively preserved
244 endoskeleton, seen in specimens of Acanthodes confusus from Lebach,
245 Germany (13,19–26). The material described here (NHMUK PV P.8065)
246 comprises part of the ventral half of the head of a specimen from the Knowles
247 Ironstone of Staffordshire. As the dorsal margins of the jawbones are
248 obscured within the rock, it was originally referred to Acanthodopsis or
249 Acanthodes. As dentition is absent, we can confirm it as Acanthodes. Most of
250 the left jaw is preserved, and of the right jaw only the mandibular splint is
251 preserved, as are some of the lower branchiostegal ray series and isolated
252 dermal gill rakers (Figs. 1k-m, S5). Scattered parts of the rest of the head
253 endoskeleton are also preserved, including parts of ceratobranchial and a
254 hyomandibular.
255 The left lower jaw comprises ossified articular and mentomandibular parts of
256 Meckel’s cartilage, as well as the mandibular splint (Figs. 1k-m, S5).
257 Mineralised parts of the Meckelian element are formed from thick perichondral
258 bone, and are slightly laterally crushed (Fig. 1m). The articular is as previously
259 described (13). The mentomandibular has a marked, cup-like fossa at its
260 anterior tip, forming part of the mandibular symphysis (Fig. S5c). The
261 mandibular splint is unornamented, slightly sinusoidal in shape, and ellipsoid 262 in cross-section. It sits in grooves in the lateral faces of the mentomandibular
263 and articular. Internally it is solid and vascularised by sparse long, thin canals
264 running its length (Fig. 1l,m).
265
266 Section 2 - Distribution of dental structures in the chondrichthyan stem-
267 group
268 Teeth and other dermal structures in stem-chondrichthyans take on a broad
269 range of forms. Here we briefly review this diversity.
270 Gnathal plates/dentigerous jaw bones
271 A number of ischnacanthiform-grade ‘acanthodians’ have large, dermal, tooth-
272 bearing jaw bones similar to those shown here in Taemasacanthus,
273 Atopacanthus, and Ischnacanthus. These are typically referred to as
274 dentigerous jaw bones, although we refer to them as gnathal plates. The
275 earliest of these come from the mid-late Silurian range from the Silurian,
276 where they often reach remarkably large sizes (over 5 cm long in
277 Xylacanthus: (27,28). They are then present through the Devonian, with the
278 latest being found in the Upper Devonian (10). By far the best understood of
279 these animals is Ischnacanthus gracilis, based on many articulated fossils
280 from the Lower Devonian Midland Valley, Scotland, and the Man on the Hill
281 (MOTH) locality in Canada (4,29). Ischnacanthus has both upper and lower
282 paired dermal jaw bones, which sit over the mandibular cartilages. Tooth
283 whorls are present on the anteriormost margins of the upper and lower jaw
284 (4), which grew by the addition of new cusps to the lingual side (30). Other 285 articulated ischnacanthiforms are less well known, but have a similar
286 anatomy. A number of genera have been erected from MOTH based on
287 differing tooth morphologies, but are otherwise identical (29). Zemlyacanthus
288 (Poracanthodes) menneri, a Lower Devonian taxon from Severnaya Zemlya
289 has upper and lower dentigerous jaw bones, in combination with tooth whorls
290 and dentition cones (31). Nerepisacanthus (32), an Upper Silurian taxon, also
291 seems to have a similar morphology, although the presence of tooth whorls is
292 uncertain. An Upper Devonian Atopacanthus sp. is reported as having
293 dentigerous jaw bones and possibly whorls (10). Acanthospina and Acritolepis
294 from the Lochkovian of Severnaya Zemlya are reported as having dentigerous
295 jaw bones and tooth whorls (33). Serradentus, from the Middle Devonian of
296 Svalbard, preserves dentigerous jaw bones, tooth whorls, and dentition cones
297 (34). More common are disarticulated dentigerous jaw bones, sometimes
298 associated with other body parts, which are presumed to belong to similar
299 ischnacanthiforms (7).
300 Mandibular splints
301 Mandibular splints (also referred to as mandibular bones, dentohyals,
302 extramandibular spines and splenials) are reported in a broad range of stem
303 chondrichthyans. They have been described in a taxonomically diverse
304 assemblage of taxa, including Acanthodes and related taxa, Mesacanthus
305 and similar taxon Promesacanthus, and the cheiracanthid Protogonacanthus
306 (but not in Cheiracanthus or Homalacanthus) (26,35–37). They are best
307 understood in acanthodids, including the taxa described here, and are broadly
308 very similar in form, although ornamented in Acanthodes sulcatus (37).
309 Although grooves for mandibular splints have been figured on isolated 310 ischnacanthid jaw elements (1), no actual splints are present in articulated
311 ischnacanthids (4,29). On the basis of our CT data, we consider this feature in
312 ischnacanthids to be a thickening of the Meckel’s cartilage, with a mandibular
313 splint being absent.
314 Occlusal jaw plate
315 Diplacanthids have a pair of smooth dermal plates in their lower gape. This is
316 termed an occlusal plate by (38) (although there is nothing for it to occlude
317 with). Similar plates are also present in Uraniacanthus, Rhadinacanthus,
318 Milesacanthus, and Culmacanthus (38–42). In the past this has become
319 terminologically confused with the mandibular splint. Tetanopsyrus, which has
320 some similarity to these taxa, seemingly has a pair of smooth occlusal plates
321 in the upper and lower jaws (43,44). An isolated pair of jaws with “teeth” have
322 also been linked to Tetanopsyrus, although these are not definitively
323 associated with a Tetanopsyrus specimen.
324 Tooth whorls
325 In many stem-chondrichthyans, teeth are organised into tooth whorls: tooth
326 files fused to a bony base, which grew by the addition of new cusps along a
327 single axis (30). These are present at the jaw symphysis in ischnacanthids
328 such as Ischnacanthus (4,26), where they grew by the addition of cusps
329 lingually. Tooth-whorl-like lip scales have also been identified in
330 ischnacanthids (45), and have been suggested to have a bearing on the
331 origins of teeth. However, given the position of iscnacanthids within the
332 gnathostome crown group, these structures seem sufficiently removed from
333 the origins of teeth to have any direct bearing. In more crownward stem 334 chondrichthyans (namely “climatiids”) many more tooth whorls are present,
335 organised into parallel rows and growing labially as with the teeth of living
336 chondrichthyans. This morphology is common in stem-chondrichthyans,
337 including those with “climatiid” features such as Doliodus, Parexus,
338 Brochoadmones, Climatius, and Vernicomacanthus (46–50). In crown-group
339 chondrichthyans the teeth are also organised this way, but have separated
340 bases.
341 Toothless forms
342 A number of stem-chondrichthyans are edentulous. Acanthodes and related
343 taxa, Mesacanthus and similar taxa, and Cheiracanthus all lack teeth and any
344 other dermal structure in the mandibular arch (18,26,36,51,52). This
345 characteristic has been used to group these taxa (37). Taxa with otherwise
346 similar morphologies, such as Euthacanthus and Brachyacanthus, also lack
347 teeth (26,53,54). Loss of teeth seems to be fairly common in early
348 chondrichthyans, as it is also present in a number of more crownward taxa,
349 including Obtusacanthus, Lupopsyrus, Kathemacanthus, and Gyracanthides
350 (55–57). Given the small nature and two-dimensional preservation of some of
351 these taxa, it is possible that teeth were present in some, but are thus far
352 undetected due to their small size. An example lies in Gladbachus adentatus,
353 a chondrichthyan which, belying its name, does in fact have teeth (15) – only
354 recently discovered with the use of microcomputed tomography.
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428 26. Watson DMS. The Acanthodian Fishes. Philos Trans R Soc Lond B Biol Sci. 429 1937 Sep 9;228(549):49–146. 430 27. Hanke GF, Wilson MVH, Lindoe LA. New species of Silurian acanthodians 431 from the Mackenzie Mountains , Canada. Can J Earth Sci. 2001;1529:1517– 432 29.
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443 31. Valiukevičius J. First articulated Poracanthodes from the Lower Devonian of 444 Severnaya Zemlya. In: Fossil Fishes as Living Animals. 1992. p. 193–213.
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480 44. Hanke GF, Davis SP, Wilson MVH. New species of the acanthodian genus 481 Tetanopsyrus from northern Canada, and comments on related taxa. J 482 Vertebr Paleontol. 2001;21(4):740–753.
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527
528 529 Links for supplementary data
530 Acanthodes_NHMUK_PV_P.8065_PLYs
531 https://www.dropbox.com/sh/7mmrrdo0shhhkc3/AABG5jhLrbghHeMghpYgizJAa?dl=0
532 Acanthodes_NHMUK_PV_P.8065_TIFFs
533 https://www.dropbox.com/sh/ao3hua7467kat40/AADUb_etPMoD_CK-c7m-E5kba?dl=0
534 Acanthodes_NHMUK_PV_P.8065_mimics
535 https://www.dropbox.com/s/x8hfru687hs8lqj/Acanthodes_NHMUK_PV_P.8065_mimics.mcs?dl
536 =0
537 Acanthodopsis_NHMUK_PV_P.10328_PLYs
538 https://www.dropbox.com/sh/2ip4lzsd56yjpyz/AAAqqq2BU6EbJ8x8Xm0TJWuTa?dl=0
539 Acanthodopsis_NHMUK_PV_P.10328_TIFFs
540 https://www.dropbox.com/sh/n24djy5n4de82bd/AABDEmru9PVyOqSHg-f_GCqNa?dl=0
541 Acanthodopsis_NHMUK_PV_P.10328_mimics
542 https://www.dropbox.com/s/9y9r7yac7p4gc0n/Acanthodopsis_NHMUK_PV_P.10328_mimics.m
543 cs?dl=0
544 Atopacanthus_NHMUK_PV_P.10978_PLYs
545 https://www.dropbox.com/sh/0kgc31bw6b1sb78/AAB0kvTiCeA__Nw4JTrKd5f3a?dl=0
546 Atopacanthus_NHMUK_PV_P.10978_TIFFs
547 https://www.dropbox.com/sh/6ceer4qkelkv8be/AABZGZqJ-tneqFvX8Ff_K7UZa?dl=0
548 Atopacanthus_NHMUK_PV_P.10978_mimics
549 https://www.dropbox.com/s/gxiyur8qo54mcxw/Atopacanthus_NHMUK_PV_P.10978_mimics.m
550 cs?dl=0
551 Ischnacanthus_NHMUK_PV_P.40124_PLYs
552 https://www.dropbox.com/sh/mrskv03iztott7s/AAChCylP9LMOYOXbYDymN_pCa?dl=0 553 Ischnacanthus_NHMUK_PV_P.40124_TIFFs
554 https://www.dropbox.com/sh/x82rgb6dx5zjv1g/AAB8f6psZiuwY-m-R-_SiK76a?dl=0
555 Ischnacanthus_NHMUK_PV_P.40124_mimics
556 https://www.dropbox.com/s/4d2bboluoes51l4/Ischnacanthus_NHMUK_PV_P.40124_mimics.mc
557 s?dl=0
558 Taemasacanthus_erroli_NHMUK_PV_P33706_PLYs
559 https://www.dropbox.com/sh/521y1zjasuff2c7/AABeQ16MiFbNKbSyMuvCG4Rva?dl=0
560 Taemasacanthus_erroli_NHMUK_PV_P33706_vol
561 https://www.dropbox.com/sh/tm798rx0ilmutqo/AADob3ja5rCoZV5Hd_D5qlt_a?dl=0
562 Taemasacanthus_erolli_NHMUK_PV_P33706_mimics
563 https://www.dropbox.com/s/qm90cxvlivd4zf8/Taemasacanthus_erolli_NHMUK_PV_P33706_mi
564 mics.mcs?dl=0