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Fig. 8 in Ontogenetic variation in the cranium of Mixosaurus cornalianus, with implications for the evolution of ichthyosaurian cranial development

Fig. 8 Mixosaurus cornalianus, isolated premaxillae. Interpretative drawings are identified by an apostrophe beside the corresponding letter. A Isolated premaxilla of a fetus PIMUZ T 4830 in medial view; B isolated premaxilla of large(?) juvenile specimen PIMUZ T 2416 in lateral view; C articulated rostrum of adult specimen MSNM BES SC 1001 in lateral view (mirrored image). ata ankylosed tooth attachment, atad lateral depression of ankylosed tooth attachment, law labial wall, liw lingual wall, max maxilla, maxf maxilla facet, naf nasal facet, pmax premaxilla. Scale bar equals 10 mm

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Fig. 14 in Ontogenetic variation in the cranium of Mixosaurus cornalianus, with implications for the evolution of ichthyosaurian cranial development

Fig. 14 Mixosaurus cornalianus, lower jaw elements. Interpretative drawings are identified by an apostrophe beside their corresponding letter. A Articulated lower jaw of a fetus of PIMUZ T 4830 in medio-dorsal view (interpretative drawing only depicts right-side); B isolated surangular of fetus PIMUZ T 4830 in medial view; C isolated left surangular of a juvenile specimen PIMUZ T 2416 in lateral view; D disarticulated right lower jaw of a juvenile MSNM BES SC 1903 in lateral view; E posterior left lower jaw of adult specimen MSNM BES SC 1001 in medial view; F articulated posterior lower jaw of adult specimen PIMUZ T 2414 in lateral view; G isolated dentary of fetus of PIMUZ T 4830 in medial view; H isolated dentary of juvenile specimen PIMUZ T 2416 in medial view; I midsection left lower jaw of adult specimen MSNM BES SC 1001 in medial view (interpretative drawing emphasizes the splenial). an angular, ar articular, ata ankylosed tooth attachment, de dentary, def dentary facet, dlaw dentary labial wall, dliw dentary lingual wall, gle glenoid, par prearticular, pcop paracoronoid process, pgl preglenoid process, sp splenial, su surangular, sym symphyseal marks, tr tooth row. Scale bar equals 10 mm

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Fig. 6 in Ontogenetic variation in the cranium of Mixosaurus cornalianus, with implications for the evolution of ichthyosaurian cranial development

Fig. 6 Mixosaurus cornalianus, isolated prearticulars and articulars. Interpretative drawings are identified by an apostrophe beside the corresponding letter. A Isolated left prearticular of a large juvenile MSNM BES SC 1903 in medial view; B isolated left prearticular of juvenile specimen PIMUZ T 2416 in medial view; C isolated right articular of a juvenile MSNM BES SC 1903 in medial view; D isolated left articular of juvenile PIMUZ T 2134 in medial view. anf angular facet, gl glenoid, ms medial surface, praf prearticular facet, spf splenial facet. Scale bar equals 5 mm

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ATACSeq fastq files associated with the manuscript entitled 'Interspecies transcriptome analyses identify genes that control the development and evolution of limb skeletal proportion'

This next-generation sequencing dataset is associated with the research manuscript entitled ‘Interspecies transcriptome analyses identify genes that control the development and evolution of limb skeletal proportion’ (https://www.biorxiv.org/content/10.1101/754002v2). The zipped folder ‘Zenodo_Saxena_etal_2021_ATACSeq_FastqFiles’ contains raw/unprocessed ATACSeq Fatsq read files for postnatal day 5 (P5) mouse (Mus) and jerboa (Jac) cartilage samples (Metatarsal = MT; Radius/Ulna = RU). > The Jac_P5 subfolder contains paired-end reads (R1 and R2) for three jerboa metatarsals (MT1-3) and radius/ulna (RU1-3) biological replicates. > The Mus_P5 subfolder contains paired-end reads (R1 and R2) for two mouse metatarsals (MT1-2) and radius/ulna (RU1-2) biological replicates.

Figure 15 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 15. Comparison of the changes between the larval and adult body plans during larval development. The horizontal axis represents developmental stages (Gosner, 1960). The curves plotted depict structural modifications, and the grey area represents metamorphic events that take place during the metamorphic climax (stages 42–46) for most anurans. The early occurrence of metamorphic events (predisplacement) is observed in the ceratophryine frogs, especially in Lepidobatrachus spp., that have precocious metamorphosis. Delayed metamorphic events take place in the development of Pseudis platensis, a species in which some morphological changes that imply the end of metamorphosis for most anurans have yet to finish.

Figure 13 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 13. Variation in structural changes in some external features. A, dorsal view of Lepidobatrachus llanensis at the end of metamorphosis. A small tail stub is present. B, lateral view of the same specimen in (A) showing the angle of the mouth far beyond the posterior margin of the eye. C, dorsal view of Chacophrys pierottii during metamorphosis. The tail has started to reduce. D, lateral view of the same specimen in (C). The disappearance of the caudal fin is advanced, and the angle of the mouth reaches the posterior margin of the eye. E and F, ventral and lateral views of a Pseudis platensis tadpole at the beginning of metamorphosis. The oral disc and keratinized buccal structures are still present, and the forelimbs have emerged, but the anal tube remains well developed. G and H, ventral and lateral views of a P. platensis tadpole during metamorphosis. Larval mouthparts have disappeared; tail regression has started with the reduction of the fins, whereas the disappearance of the anal tube is delayed. I, dorsal view of P. platensis at an advanced metamorphic stage. The tail is conserved and has reduced caudal fins. J, ventral view of the same specimen showing the absence of the anal tube, and features of the mouth that are similar to those present in most anurans at the end of metamorphosis. K, detail in lateral view of the position of the angle of the mouth posterior to the eye.

Figure 12 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 12. Hematoxylin–eosin cross sections (6-Mm thick) at the diaphyseal level of metatarsal IV in postmetamorphic specimens. Black arrowheads indicate lines of arrested growth (LAGs). A, Lepidobatrachus llanensis, five LAGs male [data for two adult males; 5 ± 1 (SVL 74.5 mm) and 6 ± 1 (SVL 74.1 mm)]. B, Lepidobatrachus laevis, six LAGs female [data for two adult females; 6 ± 1 (SVL 144 mm) and 7 ± 1 (SVL 111 mm)]. C, Chacophrys pierottii, four LAGs male [data for two adult males; 6 ± 1 (SVL 49.9 mm) and 4 ± 1 (SVL 45.2 mm)]. D, Ceratophrys cranwelli, 11 LAGs male [data for three adult males; 14 ± 1 (SVL 84.6 mm), 11 ± 1 (SVL 81 mm), and 13 ± 1 (SVL 74.3 mm)]. E, Pseudis platensis, two LAGs female [data for two adults (female and male); 2 ± 1 (SVL 46 mm) and 3 ± 1 (SVL 44.6 mm)]. F, Telmatobius atacamensis, juvenile specimen, two LAGs [data for an adult male; 5 ± 1 (SVL 45.4 mm) and for the juvenile 2 ± 1 (SVL 45 mm)]. Abbreviations: mc; marrow cavity. Scale bars: 0.05 mm.

Figure 11 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 11. Mean, maximum, and minimum values of snout–vent lengths (SVLs) in advanced tadpoles (stages 38–41), during metamorphosis (stages 42–46), and in adults. Values of SVL are given in mm. Light-grey areas approximately represent the extension of larval development (LD) in months, and dark-grey areas refer to postmetamorphic growth (PG) in lines of arrested growth (LAGs). Lepidobatrachus llanensis: SVL in tadpoles (N = 15, SVL = 36.7 ± 3.4 mm); SVL of metamorphic specimens (N = 26, SVL = 36.3 ± 5.8 mm); SVL of adults (N = 16, SVL = 76.5 ± 7.5 mm). Larval development takes place over a period of 2 weeks. Postmetamorphic growth estimated in LAGs = 6 years. Lepidobatrachus laevis: SVL in tadpoles (N = 12, SVL = 46.6 ± 2.8 mm); SVL of metamorphic specimens (N = 26, SVL = 49.9 ± 7.8 mm); SVL of adults (N = 13, SVL = 99.2 ± 22.1 mm). Larval development takes over a period of 2 weeks. Postmetamorphic growth estimated in LAGs = 7 years. Chacophrys pierottii: SVL in tadpoles (N = 10, SVL = 46.3 ± 3.9 mm); SVL of metamorphic specimens (N = 28, SVL = 36.3 ± 2.6 mm); SVL of adults (N = 15, SVL = 47.8 ± 2.7 mm). Larval development takes place over a period of 2 weeks. Postmetamorphic growth estimated in LAGs = 6 years. Ceratophrys cranwelli: SVL in tadpoles (N = 8, SVL = 26.3 ± 3.8 mm); SVL of metamorphic specimens (N = 18, SVL = 27.5 ± 4.4 mm); SVL of adults (N = 10, SVL = 91.9 ± 12.7 mm). Larval development takes place over a period of 3 weeks. Postmetamorphic growth estimated in LAGs = 14 years. Pseudis platensis: SVL in tadpoles (N = 9, SVL = 46.3 ± 3.6 mm); SVL of metamorphic specimens (N = 8, SVL = 37.4 ± 2.7 mm); SVL of adults (N = 7, SVL = 45.3 ± 5.0 mm). Larval development takes place over a period of 6 months. Postmetamorphic growth estimated in LAGs = 3 years. Telmatobius atacamensis: SVL in tadpoles (N = 11, SVL = 32.9 ± 3.4 mm); SVL of metamorphic specimens (N = 30, SVL = 31.0 ± 1.8 mm); SVL of adults (N = 2, SVL = 45.2 ± 1.0 mm). Larval development takes place over a period of 8 months. Postmetamorphic growth estimated in LAGs = 5 years.

Figure 14 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 14. Presence and absence of m. suspensoriohyoideus among selected anuran tadpoles, following the criteria proposed by Haas (2003) at larval stage 37. A, Pseudis platensis. The muscle is absent. B–F, the muscle is present. B, Telmatobius atacamensis. C, Lepidobatrachus laevis. D, Lepidobatrachus llanensis. E, Ceratophrys cranwelli. F, Chacophrys pierottii. The absence of m. suspensoriohyoideus was reported for Ceratophrys ornata, L. laevis (Ruibal & Thomas, 1988; Haas, 2003), and C. cranwelli (Vera Candioti, 2005), but Palavecino (1999) described it in C. ornata and C. cranwelli. Haas (2003) proposed that the absence of m. suspensoriohyoideus is a synapomorphy for the Ceratophrys and Lepidobatrachus clade, and Frost et al. (2006) extended the synapomorphy for Ceratophryini. Our data demonstrate the presence of the m. suspensoriohyoideous in tadpoles of the three genera of Ceratophryinae. Abbreviations: oh, m. orbitohyoideus; sh, m. suspensoriohyoideus. Scale bars: 1 mm.

Figure 9 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 9. Palmar and plantar views of the autopodia in anurans at the end of metamorphosis, where subarticular turbercles are already well defined. A, Bombina variegata (foot): subarticular tubercles are absent and metatarsal tubercles are poorly developed. B, Bombina variegata (hand): subarticular tubercles are absent. C, Odontophrynus americanus (foot): subarticular tubercles are evident, and the inner metatarsal is not yet keratinized. D, Odontophrynus americanus (hand): subarticular tubercles are strongly developed. E, Pseudis platensis (foot): tubercles are absent and the inner metatarsal tubercle is defined. F, Pseudis platensis (hand): small subarticular tubercles are evident. G, Telmatobius atacamensis (foot): small subarticular tubercles and the inner metatarsal tubercle are present. H, Telmatobius atacamensis (hand): subarticular tubercles are better defined than in the foot. I, Lepidobatrachus llanensis (foot): subarticular tubercles are absent. The well-developed inner metatarsal tubercle and toe tips are keratinized. J, Lepidobatrachus llanensis (hand): subarticular tubercles are absent. K, Lepidobatrachus laevis (foot): subarticular tubercles are absent, and the inner metatarsal tubercle presents incipient keratinization. L, Lepidobatrachus laevis (hand): subarticular tubercles are absent. M, Ceratophrys cranwellii (foot): small subarticular tubercles are defined, and the inner metatarsal tubercles are poorly keratinized. N, Ceratophrys cranwelli (hand): small subarticular tubercles are present. O, Chacophrys pierottii (foot): subarticular tubercles are not prominent. Inner metatarsal tubercle has keratinization. P, Chacophrys pierottii (hand): subarticular tubercles are well developed. The pattern of distribution of subarticular tubercles is considered as diagnostic in most species, and development of these structures takes place at larval stages 38–40 (Gosner, 1960). Subarticular tubercles in manus and pes are also absent or poorly developed in Xenopus, Hymenochirus, Pipa, Ascaphus, Leiopelma, Alytes, Discoglossus, Madecassophryne, Stumpffia, Rhinoderma, Brachycephalus, Truebella, and Ansonia (Guibé, 1978; Graybeal & Cannatella, 1995; Matsui, Nabhitabhata & Panha, 1998; Pombal & Gasparini, 2006, among others). Scale bar: 0.2 mm.

Figure 10 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 10. Total length (TL) versus snout–vent length (SVL) plotted for larval specimens of six species between stages 39 and 41. Ceratophrys cranwelli tadpoles (N = 8, TL = 61.8 ± 8.2 mm, SVL = 26.3 ± 3.8 mm) are the smallest. Pseudis platensis larvae (N = 9, TL = 129.5 ± 14.4 mm, SVL = 46.3 ± 3.6 mm) are the largest. Lepidobatrachus laevis (N = 12, TL = 98.3 ± 7.2 mm, SVL = 46.6 ± 2.8 mm) and Chacophrys pierottii (N = 10, TL = 106.5 ± 8.0 mm, SVL = 46.3 ± 3.9 mm) share with P. platensis similar values of SVL. Lepidobatrachus llanensis (N = 15, TL = 83.7 ± 7.5 mm, SVL = 36.7 ± 3.4 mm) and Telmatobius atacamensis (N = 11, TL = 84.6 ± 4.8 mm, SVL = 32.9 ± 3.4 mm) are similar in total length, but L. llanensis tadpoles have greater body sizes.

Figure 1 in Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis

Figure 1. The hypothetic relationships among ten anuran taxa that resulted from the analyses of 102 morphological characters. A, the only tree that was obtained from the analysis of larval and adult characters. B, strict consensus of relationships obtained from the analysis of 61 larval characters. C, strict consensus of relationships obtained from the analysis of 41 adult characters.

Figure 9 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 9. Development of the endogenous ovary in Epiperipatus biolleyi. Transmission electron micrographs. A, position of the ovarian anlage beneath the presumptive heart and attached to the pericardial floor (pe) in an embryo with a full number of somites. Cross-section of the dorsal body. B, cross-section of an ovarian tube. Note the distinct separation into a germinal epithelium (ge), which contains the primordial germ cells (pgc), and a sterile epithelium (se). C, detail of the sterile epithelium. D, detail of the germinal epithelium. Arrowheads indicate apical junctions. Abbreviations: bl, basal lamina; ec, ectoderm; ge, germinal ovarian epithelium; hc, haemocoel; hl, lumen of the presumptive heart; lu, lumen of the ovarian anlage; me, outer layer of mesodermal cells that will later form the ovarian musculature; nu, nucleus; pe, presumptive pericardial floor; pgc, primordial germ cells; se, sterile ovarian epithelium.

Figure 7 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 7. Internal organization of the endogenous ovary in Epiperipatus biolleyi. Light micrograph (A) and transmission electron micrographs (B–F). A, cross-section of the ovary (dorsal is up). Note the central position of ovarian lumen (lu) surrounded by germinal epithelium (ge) and the lack of a sterile epithelium. B, maturating oocyte (oc) from the germinal epithelium lying within a spherical chamber (ch), which is formed by specific cells (ce) of the germinal epithelium. C, detail of epithelial cells and an oocyte. Arrowheads indicate apical junctions. D, detail of the basal portion of the germinal epithelium with surrounding connective tissue containing muscle cells (mc). E, lower magnification of connective tissue showing numerous tracheal tubes (arrows). F, peripheral region of connective tissue containing tracheal tubes (tr) and flattened cells with an electron-dense content (fc). Abbreviations: bl, basal lamina; ce, cells of germinal epithelium that form the oocyte chamber; ch, oocyte chamber; ct, connective tissue; fc, flattened cell; ge, germinal epithelium; hc, haemocoel; lu, ovarian lumen; mc, muscle cells; mv, microvilli; nl, nucleolus; nu, nucleus; oc, maturating oocytes; tr, tracheal tubes.

Figure 5 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 5. Internal organization of the exogenous ovary in Opisthopatus roseus (A–C, E, F) and Peripatopsis balfouri (D). Transmission electron micrographs. A, detail of ovarian epithelia and lumen. Arrowheads indicate apical junctions connecting epithelial cells. B, mitotically dividing oogonium (og) from the germinal epithelium. C, maturating oocyte (oc) with associated cells (ce) of modified germinal epithelium. Arrows point to the basal lamina which is strongly folded. D, maturating oc in the process of breaking through the connective tissue and growing out into the haemocoel. E, detail of dorsal ovarian wall showing the sterile epithelium (se) and the connective tissue (ct), which contains the musculature (mc). F, higher magnification of connective tissue showing muscle cells and collagen fibres. Abbreviations: bl, basal lamina; ce, cells associated with an oocyte (sometimes referred to as 'follicle cells' in the literature); cg, collagen fibres; ct, connective tissue; ge, germinal epithelium; hc, haemocoel; he, haemocyte; lu, ovarian lumen; mc, muscle cell; mt, mitochondria; mv, microvilli; nl, nucleolus; nu, nucleus; oc, maturating oocyte; og, oogonium; se, sterile epithelium; st, growing stalk.

Figure 4 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 4. Internal organization of the exogenous ovary in Opisthopatus roseus (A, B) and Peripatopsis balfouri (C). Transmission electron micrographs. A, cross-section through the middle of the ovary. Dorsal is up. Note the unpaired lumen (lu) and the separation of the ovarian epithelium into a dorsal sterile epithelium (se) and a ventral germinal epithelium (ge). B, stalked oocytes enclosed by a vitelline membrane (= primary egg membrane). C, detail of a stalk. Arrows indicate intermediate filaments, arrowheads point to hemidesmosomes. Inset shows continuity of the basal lamina covering a stalk and a maturating oocyte that bulges into the haemocoel of the female. Abbreviations: bl, basal lamina; ct, connective tissue; ge, germinal epithelium; hc, haemocoel; lu, ovarian lumen; nl, nucleolus; nu, nucleus; oc, maturating oocytes; se, sterile epithelium; st, stalk; vm, vitelline membrane.

Figure 6 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 6. Internal organization of the pseudoendogenous ovary in Metaperipatus inae (A–E) and Metaperipatus blainvillei (F). Light micrographs (A, B) and transmission electron micrographs (C–F). A, cross-section of the ovary (dorsal is up). Note the lateral position of the crescent-shaped ovarian lumen (lu) and the central position of the germinal epithelium (ge). B, detail of stalked oocytes (oc) from the germinal epithelium, which do not bulge into the haemocoel but retain their position within the ovary. C, detail of cells (ce) surrounding a maturating oocytes in the germinal epithelium. D, detail of a stalk. Arrows indicate the intermediate filaments. E, detail of the lumen and ovarian epithelia. The epithelial cells are connected by an apical junction (arrowhead). F, lateral ovarian wall consisting of the sterile epithelium (se) and connective tissue containing muscle cells (mc), a haemocyte (he), and sperm (sh). Abbreviations: bl, basal lamina; ce, cells associated with an oocyte; cg, collagen fibres; ct, connective tissue; ge, germinal epithelium; hc, haemocoel; he, haemocyte; lu, ovarian lumen; mc, muscle cell; mv, microvilli; nl, nucleolus; nu, nucleus; oc, maturating oocyte; se, sterile epithelium; sh, sperm head; st, stalk; sw, sterile ovarian wall.

Figure 3 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 3. Diagram of internal organization of the three major ovarian types in Onychophora: exogenous ovary (A, D), pseudoendogenous ovary (B, E), and endogenous ovary (C, F). A, cross-section of the exogenous ovary with separate ovarian tubes that occur, e.g. in Euperipatoides rowelli, Phallocephale tallagandensis, and Ooperipatellus insignis (Australian Peripatopsidae). B, cross-section of the pseudoendogenous ovary of Metaperipatus inae (Peripatopsidae, Chile). C, cross-section of the endogenous ovary of Epiperipatus biolleyi (Peripatidae, Costa Rica). Note the complete lack of a sterile epithelium. D, detail of the composition of the ovarian wall in Opisthopatus roseus (Peripatopsidae, South Africa). E, detail of the ovary in Met. inae. F, detail of the ovarian wall in Ep. biolleyi. Abbreviations: bl, basal lamina; ct, connective tissue; fc, flattened cell; ge, germinal epithelium; hc, haemocoel; lu, ovarian lumen; mc, muscle cell; oc, oocyte; se, sterile epithelium; st, stalk; tr, tracheae.

Figure 1 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 1. Simplified diagrams of paired versus variously fused structure of the ovarian tubes in Onychophora. Tissues are represented in light grey, ovarian lumen in dark grey. A, exogenous ovary of Typhloperipatus williamsoni (South-East Asian Peripatidae). Modified and complemented according to descriptions given by Kemp (1914). B–D, exogenous ovaries in three species of Peripatopsidae. B, Euperipatoides rowelli (Australia). Note the completely separate ovarian tubes in the middle of the ovary and the fused ovarian lumens at the anterior and posterior ends. A similar ovarian organization has been described in Peripatoides novaezealandiae from New Zealand (Sheldon, 1890: fig. 26). C, Peripatopsis balfouri (South Africa, cf. Fig. 2A). Although the ovarian tubes are fused, their lumens are separate along their entire length. D, Opisthopatus roseus (South Africa). Note the unpaired ovarian structure with a single lumen. E, pseudoendogenous ovary of Metaperipatus inae (Peripatopsidae, Chile, cf. Fig. 2B) with fused ovarian tubes but separate lumens. F, endogenous ovary of Epiperipatus biolleyi (Neotropical Peripatidae, cf. Fig. 2C) with lumens communicating only at the posterior end. G, endogenous ovary of Mesoperipatus tholloni (Peripatidae, Tropical Africa), modified and complemented after Bouvier (1905). Each ovarian tube is completely separate in this species.

Figure 10 in Position and development of oocytes in velvet worms shed light on the evolution of the ovary in Onychophora and Arthropoda

Figure 10. Mapping of three major types of onychophoran ovaries on simplified trees representing three different hypotheses on the phylogenetic relationships of Onychophora. Onychophoran subgroups are designated by their geographical distribution. Note that the suggestion of the exogenous type as an ancestral feature of Onychophora is consistent with all three phylogenetic hypotheses. A, both Peripatopsidae and Peripatidae are monophyletic (phylogeny modified from Monge-Nájera, 1995: fig. 10). B, Peripatidae are nonmonophyletic (phylogeny simplified from Reid, 1996: fig. 29). C, Peripatopsidae are nonmonophyletic (phylogeny simplified from Reid, 1996: fig. 28).