Diplomystes,

CS) — CS-1: Presence of markedly enlarged, voluminous, circular cartilages

12. Presence of cartilaginous plates carrying the mandibular barbels (ordered multistate character) (character inspired from Ghiot, 1978). Plesiomorphically those catfish exhibiting mandibular barbels lack "cartilaginous plates carrying mandibular barbels" (see terminology of Diogo and Chardon, 2000b) [State 0: e.g. Fig. 3.92]. In all the pimelodids examined, in addition to the basal cartilages supporting the mandibular barbels usually present in most catfish (see above), there are also 'cartilaginous plates carrying mandibular barbels' (see terminology of Diogo and Chardon, 2000b). These cartilages constitute a very unique, readily recognised feature, although they are somewhat less developed in Pseudopimelodus and Microglanis [State 1: e.g. Fig. 3.110] than in the other six pimelodid genera analysed [State 2: e.g. Fig. 3.103]. — CS-0: Cartilaginous plates absent (all genera not in other CS) — CS-1: Cartilaginous plates thinner and less developed than in CS-1

(Pseudopimelodus, Microglanis — CS-2: Presence of volum inous, robust cartilaginous plates

13. Posterior bifurcation of cartilages of external mandibular barbels. Contrary to the plesiomorphic situation in those catfish with mandibular barbels [State 0: e.g. Fig. 3.26], in those few taxa of CS-1 the cartilages associated with the external mandibular barbels are posteriorly bifurcate [State 1: e g-Fig. 3.121]. — CS-0: Cartilages of external barbels not posteriorly bifurcate (all

genera not in other CS) — CS-1: Cartilages of external barbels posteriorly bifurcate

possible to discern whether they correspond to the internal pair (in

this case, the corresponding option would be 'Inapplicable') or the external (in this case, the corresponding option would be 'CS-0') (Nematogenys, Pangasius, Helicophagus, Silurus, Wallago, Rita)

14. Anteroposterior length of supporting part of cartilages of mandibular barbels. Plesiomorphically in those catfish presenting mandibular barbels the anterior, supporting parts of these cartilages are typically short [State 0: e.g. Fig. 3.92]. In Synodontis the supporting parts of the cartilages of the mandibular barbels are, however, markedly elongated anteroposteriorly, with their length approximately similar to that of the moving parts of these barbels, which are already particularly elongated in this same genus (see above) [State 1]. — CS-0: Supporting parts of cartilages not markedly elongated

anteroposteriorly (all genera not in other CS) — CS-1: Supporting parts of cartilages m arkedly elongated

15. Contact between internal mandibular barbels. Contrary to the situation found in other catfish presenting mandibular barbels [State 0: e.g. Fig. 3.5], in Cranoglanis the cartilages of the internal mandibular barbels are deeply in contact with each other on the midline [State 1: e.g. Fig. 3.60]. — CS-0: Cartilages not in deep contact with each other (all genera not

in other CS) — CS-1: Cartilages in deep contact with each other on the midline

possible to discern whether they correspond to the internal pair (in this case, the corresponding option would be 'CS-0') or the external (in this case, the corresponding option would be 'Inapplicable') (Nematogenys, Pangasius, Helicophagus, Silurus, Wallago, Rita)

16. Anterior bifurcation of retractor of external mandibular barbel. Contrary to all other catfish presenting muscles of mandibular barbels, in which the retractor of the external mandibular barbels is not bifurcate [State 0: e.g. Fig. 3.79], in Bagrus this muscle exhibits an anterior bifurcation, with its two anterior tendons being separated by the muscles protractor hyoideus and intermandibularis [State 1: e.g. Fig. 3.41]. — CS-0: Not anteriorly bifurcate (all genera not in other CS) — CS-1: Anteriorly bifurcate (Bagrus)

— ?: Since there is only one pair of mandibular barbels and it is not possible to discern whether they correspond to the external pair (in this case, the corresponding option would be 'CS-0') or the internal (in this case, the corresponding option would be 'Inapplicable') (Nematogenys, Pangasius, Helicophagus, Silurus, Wallago, Rita)

17. Presence of mesial cartilaginous complex connecting the internal mandibular barbels on the midline. Contrary to all the other catfish presenting mandibular barbels [State 0: e.g. Fig. 3.92], in the three clariid genera examined, as well as in Heteropneustes, there is a well-developed, mesial cartilaginous complex connecting the internal mandibular barbels on the midline (see terminology of Diogo and Chardon, 2000b) [State 1: e.g. Fig. 3.54]. — CS-0: Absence of cartilaginous complex connecting the internal

mandibular barbels on the midline (all genera not in other CS) — CS-1: Presence of cartilaginous complex connecting the internal

18. Presence of depressor of internal mandibular barbels (ordered multistate character). Among those catfish presenting muscles of mandibular barbels, the plesiomorphic condition seems to be that in which the depressor of the internal mandibular barbels is absent (i.e., the retractors of the barbels are present, but the depressor of the internal barbels is missing: Diogo and Vandewalle, 2003) [State 0: e.g. Fig. 3.5]. In those catfish genera of CS-1, this muscle is present [State 1: e.g. Fig. 3.76] but not as developed as in Amphilius and Paramphilius [State 2: e.g. Fig. 3.8]. — CS-0: Depressor of internal mandibular barbels absent (all genera

not in other CS) — CS-1: D epressor of in ternal m andibular barbels present

— ?: Since there is only one pair of mandibular barbels, and it is not possible to discern whether they correspond to the internal pair (in this case, the corresponding option would be 'CS-0') or the external (in this case, the corresponding option would be 'Inapplicable') (Nematogenys, Pangasius, Helicophagus, Silurus, Wallago, Rita) or since it was not possible to discern this character, due to the very small size and/or the poor condition of the specimens examined (Zaireichthys, Uegitglanis, Anadoras, Acanthodoras, Doras, Centromochlus, Auchenipterus, H elogenes, Cetopsis, Hemicetopsis, Ancharius)

19. Presence of intertentacularis. As with the depressor of the internal m andibular barbels, among those catfish presenting muscles of mandibular barbels the plesiomorphic condition seems to be that in which the muscle intertentacularis is absent (see above) [State 0: e.g. Fig. 3.5]. In those catfish of CS-1 the intertentacularis is present [State 1: e.g. Fig. 3.118]. — CS-0: Intertentacularis absent (all genera not in other CS) — CS-1: Intertentacularis present (Chrysichthys, Schilbe, Laides,

— ?: Since it was not possible to discern this character due to very small size and /o r poor condition of the specimens examined (Zaireichthys, Ancharius)

20. Presence of muscle 1 of mandibular barbels (character inspired from Ghiot, 1978). As with the depressor of the internal mandibular barbels and the intertentacularis, among those catfish presenting muscles of mandibular barbels, the plesiomorphic condition clearly seems to be that in which

the muscle 1 of these barbels is absent (Diogo and Chardon, 2000b) [State 0: e.g. Fig. 3.79], with this muscle found only in catfish of CS-1 [State 1: e.g. Fig. 3.103]. — CS-0: Muscle 1 of mandibular barbels absent (all genera not in

other CS) — CS-1: Muscle 1 of m andibular barbels present (Pimelodus,

21. Presence of muscle 2 of mandibular barbels. Plesiomorphically among those catfish presenting muscles of mandibular barbels, muscle 2 of these barbels is also absent (Diogo and Chardon, 2000b) [State 0: e.g. Fig. 3.79], with this muscle found only in the two genera of CS-1 [State 1: e.g. Fig. 3.54]. — CS-0: Muscle 2 of mandibular barbels absent (all genera not in

other CS) — CS-1: Muscle 2 of m andibular barbels present (Clarias,

22. Presence of muscle 3 of mandibular barbels. Plesiomorphically among those catfish presenting muscles of mandibular barbels, muscle 3 of these barbels is absent (Diogo and Chardon, 2000b) [State 0: e.g. Fig. 3.79]. In Amphilius this muscle is present [State 1: e.g. Fig. 3.8]. — CS-0: Muscle 3 of mandibular barbels absent (all genera not in

23. Presence of muscle 4 of mandibular barbels (character inspired from Ghiot, 1978). As noted above for muscles 1, 2 and 3 of the mandibular barbels, plesiomorphically those Siluriformes presenting muscles of mandibular barbels lack a muscle 4 of these barbels (Diogo and Chardon, 2000b) [State 0: e.g. Fig. 3.79]. In those catfish of CS-1 this muscle is present [State 1: e.g. Fig. 3.103]. — CS-0: Muscle 4 of mandibular barbels absent (all genera not in

24. Presence of muscle 6 of mandibular barbels. Plesiomorphically those catfishes presenting small muscles associated with the mandibular barbels lack a muscle 6 of these barbels [State 0: e.g. Fig. 3.79]. The only three catfish genera examined presenting a muscle 6 of the mandibular barbels running from the anteroventromesial surface of the cartilage of the internal barbel to the mandible are those mentioned in CS-1 [State 1: e.g. Fig. 3.44]. — CS-0: Muscle 6 of mandibular barbels absent (all genera not in

25. Anterior extension of cartilages of internal mandibular barbels (ordered multistate character). Contrary to the other catfishes presenting mandibular barbels [State 0: e.g. Fig. 3.92], in Malapterurus there is an anterior extension of the cartilages of the internal mandibular barbels, with the anterior margin of these cartilages situating at about the same level of the anterior margin of the mandible [State 1]. Such an anterior extension of the cartilages of the internal mandibular barbels is still more pronounced in Auchenoglanis, where the anterior margin of these cartilages extends anteriorly beyond the anterior margin of the mandible [State 2]. — CS-0: Absence of anterior extension of cartilage of mandibular barbel

(all genera not in other CS)

— CS-2: Anterior extension of cartilage of mandibular barbel more pronounced than in CS-1, with anterior margin of this cartilage extending anteriorly beyond the anterior margin of mandible (Auchenoglanis

— ?: Since there is only one pair of mandibular barbels, and, thus, it is not possible to discern if it corresponds to the internal pair (in this case, the corresponding option would be 'CS-0') or the external one (in this case, the corresponding option would be 'Inapplicable') (Nematogenys, Pangasius, Helicophagus, Silurus, Wallago, Rita)

26. Presence of muscle intermcmdibularis. Plesiomorphically catfish present a muscle intermandibularis [State 0: e.g. Fig. 3.69], but in those catfishes of CS-1 this muscle is absent [State 1: e.g. Fig. 3.9]. — CS-0: Muscle intermandibularis present (all genera not in other

size a n d /o r poor condition of the specim ens exam ined (Malapterurus, Leptoglanis, Paramphilius, Zaireichthys)

27. Development of muscle intermandibularis. The plesiomorphic condition for those catfishes presenting a muscle intermandibularis seems to be that in which these fishes present a well-developed, broad muscle intermandibularis (Diogo and Vandewalle, 2003) [State 0: e.g. Fig. 3.69]. In catfishes of CS-1, this muscle is significantly more reduced in size than in catfishes of CS-0 [State 1: e.g. Fig. 3.8]. — CS-0: W ell-developed, broad muscle in term andibularis

— CS-1: Muscle intermandibularis significantly more reduced in size than in CS-0 (all genera not in other CS)

— ?: Since, as noted above, it was not possible to appropriately discern whether the muscle intermandibularis is present (in this case, the corresponding option would be 'CS-0') or not (in this case, the corresponding option would be 'Inapplicable') (Malapterurus, Leptoglanis, Paramphilius, ZaireichthyS

28. Shape of muscle intermandibularis (character inspired from Schaefer and Lauder, 1986). Contrary to the situation found in other catfishes presenting a

muscle intermandibularis [State 0: e.g. Fig. 3.69], in Astroblepus the fibres of this muscle are not continuous on the midline [State 1]. — CS-0: Muscle intermandibularis continuous on the midline (all

genera not in other CS) — CS-1: Muscle intermandibularis not continuous on the midline

29. Attachment of protractor hyoideus. Contrary to the situation found in all other catfishes examined, in which the protractor hyoideus originates exclusively on the hyoid arch and inserts on the mandible [State 0: e.g. Fig. 3.69], in the specimens of Synodontis examined this muscle runs not only from the hyoid arch, but also from the mesial surface of the suspensorium, to the mandible [State 1]. — CS-0: Protractor hyoideus originates exclusively on the hyoid arch

(all genera not in other CS) — CS-1: Protractor hyoideus originates on the hyoid arch and

suspensorium (Synodontis) 30. Differentiation of protractor hyoideus. Plesiomorphically in catfish the muscle

protractor hyoideus is not differentiated into pars ventralis, pars lateralis and pars dorsalis (Diogo and Vandewalle, 2003) [State 0: e.g. Fig. 3.69]. In the derived condition, this muscle is differentiated into these three different parts [State 1: e.g. Fig. 3.98] — CS-0: Protractor hyoideus not differentiated into pars dorsalis,

— CS-1: Protractor hyoideus differentiated into pars dorsalis, ventralis and lateralis (all genera not in other CS)

31. Position of pars lateralis of protractor hyoideus. Contrary to the situation found in all other catfishes examined presenting a protractor hyoideus differentiated into pars lateralis, ventralis and dorsalis, in which the pars lateralis lies mainly lateral to the pars ventralis (Diogo and Vandewalle, 2003) [State 0: e.g. Fig. 3.32], in the four genera of CS-1 the pars lateralis lies completely dorsal to the pars ventralis [State 1: e.g. Fig. 3.54]. — CS-0: Pars lateralis lying mainly lateral to pars ventralis (all genera

32. Mesial aponeurosis of left and right pars dorsalis of protractor hyoideus. Contrary to the situation found in all other catfishes examined presenting a protractor hyoideus differentiated into pars lateralis, ventralis and dorsalis, in which the pars dorsalis of each side do not contact on the midline (Diogo and Vandewalle, 2003) [State 0: e.g. Fig. 3.98], in the three genera of CS-1 the pars dorsalis of each side meet mesially in a well-developed mesial aponeurosis [State 1: e.g. Fig. 3.54]. — CS-0: Pars dorsalis of each side not meeting on the midline (all

genera not in other CS) — CS-1: Pars dorsalis of each side meeting mesially on mesial

33. Relation between pars lateralis and pars ventralis of protractor hyoideus. Contrary to the situation found in all other catfishes examined presenting a protractor hyoideus differentiated into pars lateralis, ventralis and dorsalis, in which these three parts are well separated from each other [State 0: e.g. Fig. 3.8], in those few catfishes of CS-1 a large portion of the fibres of the pars lateralis is deeply mixed with those of the pars ventralis [State 1: e.g. Fig. 3.60]. — CS-0: Large portion of fibres of pars lateralis not mixed with those

of pars ventralis (all genera not in other CS) — CS-1: Large portion of fibres of pars lateralis mixed with those of

34. Mesial aponeurosis of protractor hyoideus (character inspired from Hawes, 1983a; Schaefer and Lauder, 1986). The plesiomorphic siluriform configuration is that in which the right and left portions of the protractor hyoideus (or its pars ventralis in those catfish where the muscle in differentiated into pars ventralis, dorsalis and lateralis: see above), do come into contact on a medial aponeurosis [State 0: e.g. Fig. 3.69]. This configuration changed only among all the catfish examined, in the four genera of CS-1 [State 1]. — CS-0: Presence of mesial aponeurosis of protractor hyoideus (all

genera not in other CS)

35. Shape of hyohyoideus inferior (ordered multistate character). Plesiomorphically in catfish the hyohyoideus inferior is a well-developed, somewhat triangular muscle with a marked median aponeurosis [State 0: e.g. Fig. 3.69]. In those siluriforms of CS-1 this is a hypertrophied, somewhat transversal muscle with a barely marked median aponeurosis [State 1], with its hypertrophy even more pronounced and its median aponeurosis even less distinct in catfish of CS-2 [State 2: e.g. Fig. 3.9]. — CS-0: Hyohyoideus inferior w ith fibres running essentially

anteromesially to meet in a marked median aponeurosis (all genera not in other CS)

36. Bilateral bifurcation of hyohyoideus inferior (character inspired from Schaefer and Lauder, 1986). Contrary to all other catfishes [State 0: e.g. Fig. 3.69], in the loricariid, astroblepid and scoloplacid genera examined the hyohyoideus inferior exhibits a marked bilateral bifurcation [State 1]. — CS-0: Hyohyoideus inferior not bifurcate (all genera not in other CS) — CS-1: Hyohyoideus inferior with bilateral bifurcation (Loricaria,

Hypoptopoma, Lithoxus, Astroblepus, Scoloplaid 37. Contact between hyohyoideus abductor and pectoral girdle (ordered multistate

character). Plesiomorphically the hyohyoideus abductor does not attach to the pectoral girdle (Diogo and Vandewalle, 2003) [State 0: e.g. Fig. 3.92]. In catfish of CS-1, this muscle is hypertrophied, with its median aponeurosis firmly attached to the ventral surface of the pectoral girdle [State 1]. In catfish of CS-2, the hypertrophy of this muscle is even more pronounced, and some of its fibres inserted directly on the anteroventral surface of the pectoral girdle [State 2: e.g. Fig. 3.26]. — CS-0: Hyohyoideus abductor does not come into contact with

pectoral girdle (all genera not in other CS) — CS-1: H yohyoideus abductor hypertrophied, w ith median

— CS-2: Hyohyoideus abductor even more hypertrophied, with some of its fibres inclusively inserted directly on ventral surface of pectoral girdle (Bunocephalus, Aspredo, Xyliphius, Callichthys, CorydoraS

Musculature Associated with Pectoral Girdle and Fins 38. Posteroventral attachment of stemohyoideus. Plesiomorphically in catfish

the posteroventral fibres of the stemohyoideus do not cover a significant part of the anteroventral surface of the pectoral girdle [State 0: e.g. Fig. 13.8], as is the case in the specimens examined of genera Clarias and Heterobranchus [State 1: e.g. Fig. 3.53]. — CS-0: Stem ohyoideus does not cover a significant part of

anteroventral surface of pectoral girdle (all genera not in other CS) — CS-1: Stemohyoideus covers a significant part of anteroventral

39. Posterodorsal attachment of stemohyoideus. In catfish the posterodorsal fibres of the stemohyoideus usually attach essentially on the anterodorsomesial surface of the pectoral girdle [State 0], but in the two genera of CS-1 the posterodorsal fibres of this muscle also attach on a significant part of the dorsolateral surface of this girdle [State 1]. — CS-0: Fibres of stemohyoideus attach on anterodorsomesial surface

of pectoral girdle (all genera not in other CS) — CS-1: Fibres of stemohyoideus attach not only on anterodorsomesial,

40. Position of hypoaxialis. Contrary to all other catfishes examined [State 0: e.g. Fig. 3.70], in Siluranodon the hypoaxialis is not visible in a ventral view of the anteroventral region of the body at the level of the pectoral girdle [State 1]. — CS-0: Hypoaxialis visible in ventral view of anteroventral region of

body at the level of pectoral girdle (all genera not in other CS) — CS-1: Hypoaxialis not visible in ventral view of anteroventral region

present in Siluriformes [State 0: e.g. Fig. 3.70]; uniquely in specimens examined of genus Chaca this muscle is absent [State 1: e.g. Fig. 3.50]. — CS-0: Abductor superfidalis present (all genera not in other CS) — CS-1: Abductor superficialis present (Chaca)

42. Anterior attachment of part 1 of abductor superficialis. The plesiomorphic situation for catfish is seemingly that in which part 1 of the abductor superficialis reaches the anteroventral surface of the cleithrum (Diogo et al., 2001c) [State 0: e.g. Fig. 3.70]. In the derived situation, part 1 of this muscle originates on the posteroventral, and not on the anteroventral surface of the pectoral girdle [State 1: e.g. Fig. 3.7]. — CS-0: Abductor superficialis 1 reaches anteroventral surface of the

cleithrum (all genera not in other CS)

— Inapplicable: Since the abductor superficialis is absent (Chaca) 43. Development of part 1 of abductor superficialis. Contrary to all other catfish

examined [State 0: e.g. Fig. 3.70], Siluranodon and Laides present a markedly hypertrophied abductor superficialis 1 completely covering all the ventral surface of the pectoral girdle [State 1]. — CS-0: Abductor superficialis 1 not hypertrophied (all genera not in

other CS) — CS-1: Hypertrophied abductor superficialis 1, covering all the ventral

44. Position of part 1 of abductor superficialis. Contrary to the catfish plesiomorphic situation [State 0: e.g. Fig. 3.70], in the three genera of CS-1 the abductor superficialis 1 situates on the posterior, and not on the ventral, surface of the pectoral girdle [State 1]. — CS-0: Abductor superficialis 1 situated on ventral surface of pectoral

girdle (all genera not in other CS) — CS-1: Abductor superficialis 1 situated on posterior surface of

45. Development of part 2 of abductor superficialis. Contrary to the situation found in all other catfish examined [State 0: e.g. Fig. 3.70], in Centromochlus the abductor superficialis 2 is markedly hypertrophied and not confined to the posteroventrolateral surface of the pectoral girdle, reaching its ventromesial surface [State 1]. — CS-0: Abductor superficialis 2 not hypertrophied (all genera not in

other CS) — CS-1: Hypertrophied abductor superficialis 2 reaching ventromesial

46. Subdivision of abductor profundus. Contrary to all other catfish examined [State 0: e.g. Fig. 3.71], in Amphilius the abductor profundus is subdivided into two well-developed, well-distinguished sections [State 1: e.g. Fig. 3.10]. — CS-0: Abductor profundus not differentiated into two sections (all

genera not in other CS) — CS-1: Abductor profundus differentiated into two well-developed

47. Development of abductor profundus. The plesiomorphic siluriform situation is seemingly that found in Diplomystes and many other catfish, in which the abductor profundus originates somewhat far from the mesial symphysis of the pectoral girdle, a situation that seems to be related to the plesiomorphically poorly-developed scapulo-coracoid (Diogo et al., 2001c) [State 0: e.g. Fig. 3.70]. In the derived condition, this muscle almost reaches, or does reach, the mesial symphysis of this girdle [State 0: e.g. Fig. 3.27]. — CS-0: Abductor profundus originates far from midline (Diplomystes,

— CS-1: Abductor profundus almost reaching, or indeed reaching, mesial symphysis of pectoral girdle (all genera not in other CS)

48. Development of arrector ventralis (unordered multistate character). Plesiomorphically in catfish the arrector ventralis is a well-developed muscle with its fibres running essentially transversally or slightly obliquely (Diogo et al., 2001b) [State 0: Fig. 3.70]. In catfish of CS-1, this is a relatively thin muscle with fibres running in a much more marked anteroposterior axis [State 1: Fig. 3.31]. In a completely different, peculiar and unique configuration, the specimens examined of genus Glyptostemon present a markedly hypertrophied arrector ventralis covering almost all the ventral surface of the pectoral girdle and reaching mesially the mesial symphysis of pectoral girdle [State 2]. — CS-0: Arrector ventralis well developed, fibres extending mainly

— CS-1: Relatively thin arrector ventralis with fibres running in a more marked anteroposterior axis (all genera not in other CS)

— CS-2: Markedly hypertrophied arrector ventralis covering all ventral surface and reaching mesial sym physis of pectoral girdle (Glyptostemon)

— ?: Since it was not possible to discern this character due to the highly peculiar configuration of the pectoral girdle (see below) (Cetopsis, Hemicetopsis, HelogeneS

49. Subdivision of arrector ventralis (ordered multistate character). Plesiomorphically in catfish the arrector ventralis is constituted by a single mass of fibres [State 0: Fig. 3.70]. In the amphiliin and leptoglanidin Amphiliidae, however, this muscle is differentiated into two quite distinct sections, which are associated posterolaterally [State 1: e.g. Fig. 3.7].