Zoosyst. Evol. 100 (3) 2024, 779-789 | DOI 10.3897/zse.100.117952 pg MuseuM ror BERLIN A new species of velvet worm of the genus Oroperipatus (Onychophora, Peripatidae) from western Amazonia Jorge L. Montalvo-Salazar', M. Lorena Bejarano?, Alfredo Valarezo*, Diego F. Cisneros-Heredia’*:* 1 Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biolégicas y Ambientales, Instituto de Biodiversidad Tropical IBIOTROP, Laboratorio de Zoologia Terrestre, Museo de Zoologia, Quito 170901, Ecuador 2 Universidad San Francisco de Quito USFO, Colegio Politécnico de Ciencias e Ingenierias, Departamento de Ingenieria Mecdnica, Instituto de Energia y Materiales, Quito, Ecuador 3 Universidad San Francisco de Quito USFQ, Estacion de Biodiversidad Tiputini, Orellana, Quito, Ecuador 4 Instituto Nacional de Biodiversidad, Quito, Ecuador https://zoobank. org/D477CDCE-B280-4E BC-AC4F-B8377DF 1A274 Corresponding authors: Jorge L. Montalvo-Salazar (jorgemontalvo2000@gmail.com); Diego F. Cisneros-Heredia (diego.cisnerosheredia@gmail.com) Academic editor: Pavel Stoev # Received 29 December 2023 @ Accepted 7 May 2024 @ Published 14 June 2024 Abstract The diversity of Neotropical velvet worms (Onychophora, Neopatida) is significantly underestimated, particularly within the Ande- an clade represented by the genus Oroperipatus, the last species of which was described more than 70 years ago. Here, we describe a new species of Oroperipatus from the Amazonian lowlands of Ecuador, bringing the total number of described species on mainland Ecuador to seven and in western Amazonia to three. The new species, Oroperipatus tiputini sp. nov., can be distinguished from its congenerics by the following combination of characters: two variations of primary papillae alternated between dorsal plicae; four scale ranks in the apical piece of primary papillae; reduced fifth spinous pad of legs IV and V; four supraocular papillae; occasionally reduced anterior papilla; males with two crural tubercles per leg in the first pregenital pair and a single crural tubercle per leg in the next pair; and some accessory papillae with one lateral rudimentary apical piece. We also discuss novel morphological similarities and differences with other Neopatida genera, as revealed by scanning electron microscopy (SEM). Key Words Andean peripatids, Ecuador, Neopatida, new species, taxonomy, Tiputini Biodiversity Station, Yasuni Introduction Onychophorans, commonly known as velvet worms, pos- sess a soft, elongated body covered by a lightly sclerotised cuticle, multiple locomotor limbs, and a pair of anterior slime papillae that expel a sticky slime used to immobil- ise their prey (Mayer et al. 2015). Members of the phylum Onychophora are found in tropical and subtropical re- gions around the world, with about 230 described species divided into two families: Peripatidae, with a pantropical distribution (Neotropics, Antilles, west Africa, and south- east Asia), and Peripatopsidae, with a circum-Antarctic distribution (Chile, South Africa, New Guinea, Australia, and New Zealand) (Monge-Najera 1995; Oliveira et al. 2012; Giribet et al. 2018). Neotropical peripatids form the clade Neopatida and are divided into two lineages: the “Andean peripatids”, represented by species of the genus Oroperipatus Cockerell, 1908, and the “Caribbean peri- patids”, comprising all other neopatid genera (Giribet et al. 2018; Costa and Giribet 2021). Oroperipatus is characterised by four or more foot papillae and a nephridial tubercle on legs IV and V insert- ed in a complete third spinous pad (Bouvier 1905; Clark 1913; Costa et al. 2021). While knowledge of the diver- sity of Caribbean peripatids has significantly increased (e.g., Morera-Brenes and Najera 2010; Costa et al. 2018; Barquero Gonzalez et al. 2020; Costa and Giribet 2021), the most recent descriptions of Oroperipatus species date Copyright Montalvo-Salazar, J.L. et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 780 back over 70 years (du Bois-Reymond Marcus 1952). Currently, twenty species of Oroperipatus are known from México, Panama, Colombia, Ecuador, Peru, Bolivia, and Brazil, with a wide altitudinal range from the Pacific coast to the high Andes and the Amazonian lowlands (Bouvi- er 1905, Fuhrmann 1915; Clark and Zetek 1946; Sam- paio-Costa et al. 2009; Oliveira 2023). In South America, only two described species have been reported from the lowlands of western Amazonia: Oroperipatus bluntschlii (Fuhrmann, 1915), from the area of the Samiria and Lagar- tococha rivers, Loreto, Peru, and O. weyrauchi (Bois-Rey- mond Marcus, 1952), from Yurac, River Aguaytia, Ucaya- li, Peru (Fuhrmann 1915; du Bois-Reymond Marcus 1952; Icochea and Ramirez 1996). In this contribution, we are pleased to describe a new species of Oroperipatus from the northern Amazonian lowlands of Ecuador. Methods We conducted fieldwork at the Tiputini Biodiversity Sta- tion (TBS), situated approximately 280 km ESE of Quito, in the Orellana province, Republic of Ecuador. Established in 1994 by Universidad San Francisco de Quito (USFQ), TBS is a research station spanning 744 hectares of un- disturbed lowland evergreen rainforest on the northern bank of the Tiputini River, within the Yasuni Biosphere Reserve — one of the planet’s most biodiverse regions (Cisneros-Heredia 2003, 2006; Bass et al. 2010; Blake et al. 2012; Ryder and Sillett 2016; Romo et al. 2017). The station encompasses various habitats, including Terra Firme Forest, Varzea Forest, small areas of Igapo Forest, palm swamps, and natural gaps. Mean annual precipita- tion ranges between 2700 and 3100 mm, with a relative- ly aseasonal climate characterised by peak rainfall from April to August and drier conditions from November to March and August (Cisneros-Heredia 2003, 2006; Blake et al. 2012; Ryder and Sillett 2016; Romo et al. 2017). Opportunistic collections were conducted at night on trails at TBS in April—July 2001, June 2017, May—June 2018, April-May 2019, May—June 2022 and June 2023. Specimens were collected by hand, placed in plastic bags with leaf litter for transportation to the laboratory, photo- graphed alive, and then euthanised and preserved in 75% ethanol. Additionally, we examined specimens deposited by previous researchers at the Museo de Zoologia, Uni- versidad San Francisco of Quito, Ecuador (ZSFQ). All specimens of the type series are deposited at ZSFQ. Jaws are preserved in glycerol in microvials alongside their respective specimens. Information for comparative diag- noses was obtained from the original descriptions and the comprehensive revision by Bouvier (1905). Description, character definition, and terminology ad- here to standards proposed by Oliveira et al. (2010, 2012). We followed the definition of antennal tip by Oliveira et al. (2010) due to the undetected chemoreceptors (see Remarks). The concept of diagnosis is used as proposed by the ICZN (1999). Specimens were examined using zse.pensoft.net Montalvo-Salazar, J.L. et al.: New Oroperipatus from western Amazonia an Olympus SZX16 stereomicroscope. To facilitate jaw extraction and minimise mouth damage, specimens were rehydrated using gradually lowered ethanol concentra- tions (from 75% to 10%) and warm water for five hours. Jaws were then placed on a slide with gel alcohol and observed under an Olympus CX22 optic microscope. All measurements were taken in preserved specimens under a stereomicroscope with a Truper digital vernier calliper (0.05 mm accuracy, rounded to the nearest 0.1 mm) and reported as a mean + standard deviation (range, sample size). Specimens were studied and photographed using an Olympus SZX16 stereomicroscope with an Olympus DP73 digital camera attached. Photographs shown in Fig. 3 were obtained by photograph stacking using Com- bineZP 1.0 software and then adjusted for brightness and contrast to highlight taxonomically important structures with Adobe Photoshop CC 2020 software (Adobe Sys- tems, USA). Raw photographs are available at http://do1. org/10.5281/zenodo. 10864497. Photographs in other fig- ures were not adjusted. Descriptions of colouration in life are based on digital in-situ photographs. We used scanning electron microscopy (SEM) to study the morphology of the tegument. One male paratype (ZS- FQ-18004) preserved in 75% ethanol was dissected to ex- tract samples of its dorsal tegument, legs, antenna, and genital pad. Images were captured using a JEOL JSM- IT300L SEM at 15 kV with a working distance of 13 mm, operated under low vacuum conditions (30 Pa) and a high probe current of 40 nA. Samples were carefully dried by natural convection on a petri dish using a fluorescent lamp for 20 minutes. This method was chosen due to the lack of a critical point dryer. Samples were gold-coated for 1 minute and electrically grounded to the stage using carbon tape. We conducted this research under research permits (006-2015-FAU-DPAP-MA, 001-16 IC-FLO-FAU-DNB/ MA, 018-2017-IC-FAU-DNB/MAE, 019-2018-IC-FAU- DNB/MAE, and MAAE-ARSFC-2022-2204) issued by the Ministry of Environment of Ecuador. Results Oroperipatus tiputini sp. nov. https://zoobank.org/F37273EE-10A9-49D7-A332-8B354F 12DCBC Figs 1-5 Material examined. Holotype. Ecuapor * 9, prov- ince of Orellana, Tiputini Biodiversity Station; -0.637, -76.152; 220 m elevation; 6 Jun. 2022; Pedro Pefiaherre- ra-R., Roberto J. Leon-E., and Diego F. Cisneros-Heredia leg.; ZSFQ-18249 Paratypes. Ecuapor * 1 3, same locality data as holo- type; 22 May 2018; Diego F. Cisneros-Heredia, Francisco Velasquez, and Juan Pablo Jordan leg.; ZSFQ-15151; ¢ 1 &, same locality data as holotype; 21 May 2019; Fran- cisco Velasquez and Diego F. Cisneros-Heredia leg.; ZS- FQ-i8004, * 1 3’, same locality data as holotype; 13 Apr. Zoosyst. Evol. 100 (3) 2024, 779-789 Intraocular arch Frontal arch Supraocular papillare Chitinous extension 781 Ocular arch Antenna rings 200 um Figure 1. Illustration of the head morphology around the eye of Oroperipatus tiputini sp. nov. showing four supraocular papillae, the chitinous extension, and frontal, intraocular, and ocular arches. : Inner jaw Outer jaw x Figure 2. Drawing of the outer and inner jaws of Oroperipatus tiputini sp. nov.;, the black arrow points to the diastema. Scale bar: 0.2 mm. 2021; K. Faloon leg.; ZSFQ-8250; * 1 4, same locality data as holotype; 30 Jun. 2023; Montalvo, J. leg. ZS- FQ-i17992+ 1 &, same locality data as holotype; 8 Jun. 2022; Pedro Pefiaherrera-R., Roberto J. Leon-E., and Di- ego F. Cisneros-Heredia leg.; on the root of a Ceiba tree; ZSFQ-1i8270; 1 2 and 1 juvenile, same locality data as ho- lotype; 7 Jun. 2017; Diego F. Cisneros-Heredia leg.; ZS- FQ-15143, ZSFQ-117793; * 1 juvenile, same data as holo- type; ZSFQ-117794; « 1 9, same locality data as holotype; 25 May 2022; Diego F. Cisneros-Heredia, Paula Leoro and Maria Sol Salazar leg.; ZSFQ-i8248. * 1 juvenile, same locality data as holotype; 30 Jul. 2001; Diego F. Cisner- os-Heredia leg.; ZSFQ-i5149. Type locality. Tiputini Biodiversity Station (-0.637, -76.152, 220 m elevation), provincia de Orellana, Republica del Ecuador. Diagnosis. Oroperipatus tiputini sp. nov. differs from all other congeneric species by having two size variations of primary papillae alternated between dorsal plicae (Figs 3A, 4C), apical piece of primary papillae with four scale ranks (Fig. 4B), reduced fifth spinous pad of legs IV and V (Fig. 3B), four foot papillae, four supraocular papil- lae, and occasionally the anterior papilla reduced (Fig. 1); some accessory papillae with one lateral rudimentary api- cal piece (Fig. 4C); males with two crural tubercles per leg in first pregenital pair and a single crural tubercle per leg in the next pair (Fig. 3C). Oroperipatus tiputini sp. nov. 1s most similar to O. lank- esteri by having dorsal plica alternation, two variations of primary papillae alternated between dorsal plicae, two to three accessory teeth in outer jaw, one to two accessory teeth in inner jaw, reduced fifth spinous pad of legs IV and V, and seven rings on tip of antenna. However, O. tiputini Sp. nov. is distinguished from O. /ankesteri (characters in zse.pensoft.net 782 £ ¥ +; J ‘ a Montalvo-Salazar, J.L. et al.: New Oroperipatus from western Amazonia Figure 3. Tegument and leg morphology of Oroperipatus tiputini sp. nov. A. Dorsal integument. B. Ventral detail of the right V leg showing five spinous pads and a nephridial tubercule (np) indented at the third spinous pad. C. Genital pad (gp) and pregenital legs of the right side showing the crural tubercules pointed by white arrows. Scale bars: 1 mm (A); 0.2 mm (B); 0.4 mm (C). parentheses) by having a well-developed diastema (short diastema), absence of distal foot papillae, and always pre- senting two anterior and posterior foot papillae (five to seven foot papillae with distal papillae); third spinous pad divided into two unequal fragments by nephridial tuber- cle (nephridial tubercle at posterior edge of third spinous pad without dividing it); a smaller frontal organ (size as five to six papillae); four supraocular papillae (two); and one to three accessory papillae between primary papillae (uniformly three accessory papillae). Oroperipatus tipu- tini sp. nov. differs from O. ecuadoriensis (characters in parentheses), a species similar to O. lankesteri, by having reduced fifth spinous pad in IV and V pairs of legs (same width as other spinous pads), two variations of primary papillae (three), hyaline organs inconspicuous (conspicu- ous), incomplete plicae in every segment (some segments without incomplete plicae), four foot papillae (five to six), zse.pensoft.net a smaller frontal organ (size as five to six papillae), and ac- cessory papillae more abundant (rare on dorsum and more abundant on flanks). Oroperipatus tiputini sp. nov can be differentiated from O. weyrauchi and O. bluntschlii, the other two described species from the Amazonian lowlands (characters of O. weyrauchi and O. bluntschlii in paren- theses) by having two pair of crural tubercles in pregenital pair of legs (one pair in O. weyrauchi), legs with more number of transverse leg rings (17—18 in O. tiputini vs. 14 in O. weyrauchi), four foot papillae (some legs with five in O. weyrauchi and O. bluntschlii), two types of primary papillae (primary papillae greatly varies in size with all in- tergradations to accessory papillae), diastema well-devel- oped (short diastema in O. bluntschlii), five spinous pad (sixth vestigial spinous pad in O. bluntschiii), and biggest primary papillae disposed on large plicae (biggest primary papillae in all segments). Zoosyst. Evol. 100 (3) 2024, 779-789 783 Figure 4. Antenna, dorsal integument, and genital pad morphology of Oroperipatus tiputini sp. nov. under a scanning electron mi- croscope. A. Antenna: in blue, the antennal tip, and in yellow, the sensory field of the antenna; insert in A: spindle-shaped papillae in detail. B. Primary papilla with 10 scale ranks in the basal piece (bp), four scale ranks in the apical piece (ap), and the sensory bristle (sb). C. Dorso-lateral integument: in green, the biggest primary papillae; in purple, the smallest primary papillae (or second- ary papillae); and in red, the accessory papillae that possess rudimentary apical pieces; the arrow points to the incomplete plica. D. Posterior region in ventral view showing the opening of the genital pad (gp) and, in orange, the anal glands. Scale bars: 200 um (A, C, D), 50 um (B and insert in A). Description. Head. Antennal rings 40 to 52. Antennal tip with 14 antennal rings alternated type I and type I sensillum; smallest rings only with type II sensillum (Fig. 4A). Antennal chemoreceptors not detected. Ventrally, from ring 17 to base of the antenna, spindle-shaped papil- lae form sensory field of antenna (Fig. 4A). Slightly wrin- kled eyes laterally behind base of antennae. Ocular and frontal arches with large primary papillae and intraocular arch formed by smaller primary papillae and accessory papillae. Intraocular arch interrupted, with a chitinous ex- tension under eye (Fig. 1). A frontal organ located ventral behind base of antennae and equivalent in size to four to five anterior dermal papillae. Mouth with seven pairs of lobes or internal lips (although in some specimens is dif- ficult to distinguish most posterior pair) and unpaired lip. One to three accessory teeth in outer jaw and two or three accessory teeth in inner jaw with deep diastema, followed by seven to nine denticles (Fig. 2). Dorsal integument. Plicae per segment 12, alternating between large and narrow, ten complete plicae and two incomplete plicae and irregular above base of legs; seven plicae overpass between legs to venter. Dorsomedian fur- row continuously and flanked by one to three accessory papillae on both sides. Two variations of primary papil- lae, ovoid. Biggest primary papillae on the large plicae, while smallest primary papillae (or secondary papillae) on every plica. Primary papillae separated by one to three accessory papillae, more frequently by three (Figs 3A, AC). Primary dermal papillae cylindrical. Apical pieces with four scale ranks. Basal pieces with ten scale rank in largest primary papillae and nine in smallest primary dermal papillae. Scales of apical pieces elongated, three zse.pensoft.net 784 Montalvo-Salazar, J.L. et al.: New Oroperipatus from western Amazonia ° _s Want of = eee hd ee ie Figure 5. A—C. Colour variation in the life of Oroperipatus tiputini sp. nov. A. Adult male paratype, ZSFQ-18270; B. Adult male paratype, ZSFQ-15151; C. Adult female holotype (ZSFQ-i8248) and youngling paratype (ZSFQ-17794) a few days after being born. All photographs were taken at the Tiputini Biodiversity Station. Photographs by Pedro Pefiaherrera R. (A, C) and Diego F. Cisneros-Heredia (B). times larger and half wider than scales of basal pieces (Fig. 4B). Ventral integument. Visible ventral organs. Preventral organs inconspicuous. Legs. Transverse rings 17 to 18. Pairs of legs IV and V with four first spinous pads of the same size and fifth one reduced. Proximal margin of third spinous pad indent- ed by nephridial tubercle and separate not completely into two unequal segments (Fig. 3B). Three spinous pads on last pair of legs plus one vestigial, four spinous pads on penulti- mate pair of legs, and four spinous pads on first pair of legs. Last pair of legs not rotated and used for walking. Eversible coxal vesicle present but not seen in all legs. Two anterior foot papillae and two posterior foot papillae. Two bristles on distal and proximal setiform ridges. Females with 37-40 pairs of legs and males with 34—36 pairs of legs. Posterior region. Genital opening of females and males cruciform (Fig. 4D). Crural tubercles on four pre- zse.pensoft.net genital legs of the male: two crural tubercles per leg in first pregenital pair, and a single crural tubercle per leg in the next pair (Fig. 3C). Concolorous slit-like anal glands in males. Colouration. One adult male (ZSFQ-i8270) was brown with faded rhomboids (Fig. 5A); two adult males and one adult female (15151, 117992, 8248; Fig. 5B) were brown with orange diamonds; an adult female (ZS- FQ-18249, holotype) was completely plain dark orange and the youngling it gave birth was yellowish with di- amond-shaped dorsal patterns (ZSFQ-i17794; Fig. 5C). All specimens, juveniles and adults, have a very conspic- uous anterior white band with a heart-shaped border along midline (Fig. 3). All specimens show head and antennae darker than dorsum, and orange or brown legs. Preserved specimens show high depigmentation, with background colouration changing from pale orange or brown to white and dorsal patterns lost or blurred. Zoosyst. Evol. 100 (3) 2024, 779-789 80°o'o"W 2°0'0"N 0°0'0" 2°0'0"S 4°0'0"S 6°0'0"S 80°0'O"-W 78°0'0"W 78°0'O"W 785 76°0'O"W 2°0'0"N 0°0'0" 2°0'0"S 4°0'0"S Altitude 6300 , Coordinate System: GCS WGS 1984 Datum: WGS 1984 Units: Degree Sources: Esri, USGS, NOAA 76°0'O"W 6°0'0"S Figure 6. Map of Ecuador showing the location of the Tiputini Biodiversity Station (white square), type locality of Oroperipatus tiputini sp. nov., in the Amazonian lowlands. Measurements. Holotype in preservative (in mm): Length: 48.1, width: 3.15, number of pairs of legs: 40. All preserved specimens (in mm): Length of females: 52.6 + 11.0 (46-65.3, n = 3), width of females: 4.7 + 1.6 (3.2-6.3, n = 3); length of males: 32.5 + 6.9 (22.7-39.8, n=5), width of males: 3.4 + 0.9 (2.04.3, n = 5); length of juveniles: 30.1 + 4.4 (25.5—34.3, n= 3), width of juve- niles: 2.9 + 0.4 (2.5-3.3, n=3); number of pairs of legs in females: 37-40, number of pairs of legs in males: 34-37. Etymology. The specific epithet is used as a name in apposition in reference to the type locality of the new species, Tiputini Biodiversity Station (TBS). We present this new species in recognition of the hard work done to protect Amazonian biodiversity by TBS’s management, research, and field team at one of the most important re- search stations in western Amazonia (Bass et al. 2010). Distribution and natural history. The species is cur- rently known only from the type locality, Tiputini Bio- diversity Station, in the northern Amazonian lowlands of Ecuador (Fig. 4). Most individuals of O. tiputini sp. nov. have been found in old-growth, closed-canopy Terra Firme forests, on the leaves and stems of small forbs at less than 70 cm above ground, 1n leaf litter, and on but- tress roots. One specimen (ZSFQ-18250) was found inside a bromeliad. Most specimens were found active at night (19h00—23h00), except for a male individual active on a tree trunk, 1.5 m above the floor in old-growth Varzea forest, at 16h00. Individuals have been found singly or in pairs. In captivity, the female holotype (ZSFQ-i8248) gave birth to a single youngling (ZSFQ-i17794) (Fig. 5C), staying together for three days until euthanised; during that time, the juvenile remained surrounded by the mother or on her back. One adult male (ZSFQ-117992) was caught using a baiting net at 1 m height in the vege- tation during the day. Remarks. One male specimen (ZSFQ-15151) exhibit- ed a different number of legs on each side, with 35 on the right and 36 on the left. The new species undergoes on- togenic colour changes, as shown by the uniform dorsal colouration of the adult female holotype compared with the rhomboid pattern over a yellowish background of its youngling. Juveniles display brighter colours (lighter yel- low and rhomboid pattern), which darken with age, and the rhomboid pattern fades in males or is lost in females. zse.pensoft.net 786 We encountered challenges with two characters in our SEM images. Spindle-shaped papillae appeared notably flattened (Fig. 4A), a condition not previously reported in Onychophora. Additionally, antennal chemoreceptors were not detected, a feature only reported in Mongeperi- patus. We think these characters were affected by the SEM preparation method. During our examination, technical limitations prevent- ed a thorough review of certain structures, notably the interpedal structures. However, as these structures are not described for any other Oroperipatus species and a comparative analysis was unfeasible, we deemed them non-essential for the purposes of our study aimed at de- scribing a new species. Discussion The description of Oroperipatus tiputini sp. nov. brings the total number of described velvet worm species from mainland Ecuador to seven. This species is the first de- scribed from the Amazonian lowlands of Ecuador and the third from western Amazonia. Most velvet worm species from Ecuador are known only from their type localities, and, in some cases, their taxonomy 1s unclear and requires further revision (Table 1) (Oliveira 2023). Morphological- ly, O. tiputini sp. nov. 1s more similar to O. /ankesteri than to O. weyrauchi or O. bluntschli, despite the last two be- ing the only congeners inhabiting the Amazon basin. The Montalvo-Salazar, J.L. et al.: New Oroperipatus from western Amazonia morphological similarities between O. tiputini sp. nov. and O. lankesteri could indicate an evolutionary relationship; however, without additional data, proposing any phyloge- netic hypothesis would be premature. Oroperipatus lank- esteri is known solely from its type locality, Paramba, in the northern Pacific lowlands of Ecuador (Table 1). While O. tiputini sp. nov. 1s easily diagnosed from O. weyrauchi and O. bluntschiii, it is important to note that the descrip- tions of both species lack certain important characters and others are only presented in figures, making interpretation difficult. The author of these descriptions emphasised characters such as pigmentation, leg number, and denti- tion, which can be variable. The holotype of O. bluntschli was fixed with formaldehyde (Fuhrmann 1915), likely causing deformation of its tegument. The number of leg pairs in onychophorans is related to the length of the in- dividual; however, this variability is low in many species (Monge-Najera, 1994). Therefore, it could be useful for distinguishing certain species if length-related correla- tions are accounted for (Monge-Najera 1994). The male reported for O. weyrauchi had a length (in 75% ethanol) of 35 mm (du Bois-Reymond Marcus 1952), which falls within the range of O. tiputini sp. nov. Thus, the number of leg pairs could be comparable, with O. weyrauchi hav- ing more leg pairs (40) than O. tiputini sp. nov. (34-37). Moreover, the female of O. weyrauchi, which was 10 mm longer than the male, had fewer leg pairs (38) than the male, while females of O. tiputini sp. nov. have a higher number of leg pairs than males. Table 1. Described species of Oroperipatus (Onychophora, Peripatidae) currently known from mainland Ecuador. Author Schmarda, 1871 Species Oroperipatus quitensis Known distribution Described from the unspecific locality “Aequatorial-Hochland” (= Equatorial highlands), subsequently reported from the valley of Quito, northern Andean highlands? Sources Schmarda (1871); Bouvier (1905); Correoso Rodriguez (2011) Oroperipatus corradoi Camerano, 1898 Oroperipatus cameranoi Bouvier, 1899 Oroperipatus lankesteri Bouvier, 1899 Oroperipatus ecuadoriensis Bouvier, 1902 Oroperipatus belli Bouvier, 1904 Surroundings of Quito, northern Andean highlands, but also reported from Guayaquil, Balzar and River Giron on the western Andean slopes of Ecuador, and from localities in Panama and Venezuela Sigsig and Cuenca, southern Andean highlands Paramba, northern Pacific lowlands? Bulim (nowadays Pulun), northern Pacific lowlands? Duran, southern Pacific lowlands Camerano (1898); Bouvier (1905); Clark (1914a, 1914b); Brues (1925): Clark and Zetek (1946); Ribera (1977) Camerano (1897); Bouvier (1905) Bouvier (1899, 1905) Bouvier (1902, 1905) Bouvier (1904, 1905) Montalvo-Salazar & Cisneros- Heredia, 2023 Oroperipatus tiputini sp. nov. ''We consider the record of O. quitensis from the northern Amazonian lowlands of Ecuador presented by Read (1988) to be in error and correspond to a different, unidentified species. > See Reyes-Puig et al. (2020) for details about the location of Paramba. > See Paynter (1993) for details about the location of Bulim or Pulun. zse.pensoft.net Tiputini Biodiversity Station, northern Amazonian lowlands This paper Zoosyst. Evol. 100 (3) 2024, 779-789 The rhomboid pattern on the dorsum of O. tiputini sp. nov. has been reported in O. weyrauchii (du Bois-Rey- mond, 1952). Field observations suggest this dorsal pat- tern with some colour variations could be widespread 1n described and undescribed species from the Ecuador- ian and Peruvian Amazonia. The colouration ontogenic changes evidenced in O. tiputini sp. nov. are apparently responsible for the significant colour variation observed in the new species. It would be the first case of drastic co- lour ontogenic changes reported in Onychophora. It has been reported that there are variable intraspecific coloura- tions within the same brood in some species of Peripa- topsidae (Ruhberg & Daniels, 2013), and three stages of pigmentation in juveniles of the Peripatoides novaezea- landiae complex have been distinguished, getting more pigmented and lustred between 25 and >50 days after birth (Pripnow and Rhuberg 2003). Ontogenetic colour changes have been reported in several species of terrestri- al arthropods and are related mainly to anti-depredation mimicry and aposematism (Booth 1990). Oroperipatus tiputini sp. nov. presents four scale ranks in the apical pieces of the primary papillae. The number of scale ranks in the apical pieces varies interspecifical- ly from four to five in Oroperipatus, a characteristic that helps differentiate it from most Epiperipatus (except for E. adenocryptus, Oliveira et al 2011) and Macroperipa- tus, which has three or fewer scale ranks (Read 1988; Chagas-Junior and Costa 2014). Read (1988) reported that Oroperipatus was divided into two groups based on the shape of the primary papillae.Oroperipatus tiputini sp. nov. is more closely related to what Read (1988) iden- tified as Oroperipatus quitensis, although it probably be- longs to an undescribed species given its conical-shaped apical piece and Amazonian locality. In contrast, O. cor- radoi and O. eisenii present spherical apical pieces. The number of scale ranks in the basal piece of the dermal papilla shows intraspecific variation and lacks taxonomic relevance. Currently, no additional SEM characters can be used to compare O. tiputini sp. nov. with other species of Andean peripatids. It is necessary to explore the mor- phological diversity of Oroperipatus due to its usefulness in onychophoran taxonomy (Oliveira et al. 2012; Barque- ro Gonzalez et al. 2020). The arrangement of antennal sensilla in O. tiputini sp. nov. does not differ from that in other species of Neotrop- ical peripatids. The spindle-shaped papilla presents two scale ranks, as seen in other known peripatid species (Ol- iveira et al. 2012). The shape of the gonopore opening re- sembles that of other Andean species, such as O. quitensis and O. eisenii (Bouvier 1905; Contreras-Félix et al. 2018), and does not vary between sexes, as is the case in Eoperi- patus and Principapillatus (Oliveira et al. 2012, 2013). There are some morphological similarities between Oroperipatus tiputini sp. nov. and Mongeperipatus in characters otherwise considered restricted to Mongeperi- patus, including the absence of hyaline organs, the pres- ence of four scale ranks in the apical piece (although it varies from four to seven in Mongeperipatus), and the 787 alternation between the largest and mid-sized primary papillae in the dorsal plicae. Also, Oroperipatus tiputini sp. nov. shares with Mongeperipatus kekdldi the absence of antennal chemoreceptors and the presence of accessory papillae with lateral apical rudimentary pieces. Currently, it is unknown whether these characteristics are present in other species of Oroperipatus, due to the poor SEM exploration of Andean peripatids. These morphological similarities are likely the result of convergence, as phylo- genetic analyses have placed Mongeperipatus in the Ca- ribbean peripatid clade (Barquero Gonzalez et al. 2020). Acknowledgments We express our gratitude to Emilia Pefiaherrera-Romero for her constant support and companionship at the Tipu- tini Biodiversity Station and the Laboratory of Terrestrial Zoology of Universidad San Francisco de Quito; to all the students of the course of Tropical Ecology that accom- panied us to the Tiputini Biodiversity Station; to all the management, administrative and field staff of the Tiputini Biodiversity Station for their support during fieldwork along the years, especially David Romo, Consuelo Bar- riga, Gonzalo Rivas, Catalina Ulloa, Jaime Guerra, Tomi Sugahara, Zoila Rivera, Carla Larrea, Mayer Rodriguez, Ramiro Sanmiguel, and José Macanilla; to David Torres and Melannie Nufiez for their help in the translation and interpretation of articles written in French and German; to Kelly Swing for providing photographs of living speci- mens and sharing natural history information; to Krutska- ya Yépez for her support during scanning electron micros- copy; to Giovanni Ramon and Margarita Lopez, curators of the invertebrate collection at the Museo de Zoologia, Universidad San Francisco de Quito, for their constant support; to two anonymous reviewers for their valuable comments on the manuscript; and to Biodiversity Heri- tage Library BHL, Internet Archive, Google Books, the library system of Universidad San Francisco de Quito, and Sci-Hub for making important literature available. We acknowledge the role of Sci-Hub in providing free access to important literature that otherwise would be be- hind paywalls, recognising both its contribution to facili- tating research and the complex ongoing debates regard- ing scholarly publishing practices and access (Greshake 2017; Himmelstein et al. 2018). The work by Jorge L. Montalvo-Salazar was supported by Diego Montalvo, Wilma Salazar, Maria Paz Rueda, Giovani Ramon, and Galilea Pérez. The work by Diego F. Cisneros-Heredia was supported by Maria Elena Heredia, Laura Heredia, Jonathan Guillemot, David Romo, and Consuelo Barriga. Universidad San Francisco de Quito USFQ supported this work through research grants awarded to Diego F. Cisne- ros-Heredia by the office of the Dean of Research, the College of Biological and Environmental Sciences, and the Tiputini Biodiversity Station; and through research, outreach, and operative funds assigned to the Institute of Tropical Biodiversity (IBIOTROP). zse.pensoft.net 788 References Barquero Gonzalez JP, Sanchez-Vargas S, Morera-Brenes B (2020) A new giant velvet worm from Costa Rica suggests absence of the ge- nus Peripatus (Onychophora, Peripatidae) in Central America. Revis- ta de Biologia Tropical 68. https://doi.org/10.15517/rbt.v68i1.37675 Bass MS, Finer M, Jenkins CN, Kreft H, Cisneros-Heredia DF, Mc- Cracken SF, Pitman NCA, English PH, Swing K, Villa G, Fiore AD, Voigt CC, Kunz TH (2010) Global Conservation Significance of Ecuador's Yasuni National Park. PLoS One 5: e8767. https://doi. org/10.1371/journal.pone.0008767 Blake JG, Mosquera D, Loiselle BA, Swing K, Guerra J, Romo D (2012) Temporal activity patterns of terrestrial mammals in lowland rainforest of eastern Ecuador. Ecotropica (Bonn) 18: 137-146. du Bois-Reymond Marcus E (1952) On South American Malacopoda. Boletins da Faculdade de Philosophia, Sciencias e Letras, Universi- dade de Sao Paulo. Zoologia 17: 189-209. https://doi.org/10.11606/ issn.2526-4877 bsffclzoologia.1952.125190 Boot CL (1990) Evolutionary significance of ontogenetic colour change in animals. Biological Journal of the Linnean Soci- ety. Linnean Society of London 40(2): 125-163. https://doi. org/10.1111/j.1095-8312.1990.tb01973.x Bouvier EL (1899) Nouvelles observations sur les Péripates américains. Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences 129: 1029-1031. https://doi.org/10.5962/bhlI.part.26693 Bouvier EL (1902) Le Peripatus ecuadoriensis. Bulletin de la Société Philomathique de Paris 4: 53-62. https://doi.org/10.5962/bhl. part. 19238 Bouvier EL (1904) Peripatus belli (espéce nouvelle de I'Equateur). Bul- letin du Muséum National d'Histoire Naturelle 10: 56-57. Bouvier EL (1905) Monographie des Onychophores. Annales des Sci- ences Naturelles. Zoologie 2: 1-383. Brues CT (1925) Notes on Neotropical Onycophora. Psyche (Cambridge, Massachusetts) 32: 159-165. https://doi.org/10.1155/1925/79079 Camerano L (1897) Sul Peripatus quitensis Schmarda. Atti della Reale Accademia della Scienze di Torino 32: 395-398. Camerano L (1898) Viaggio del Dr. Enrico Festa nella Repubblica dell’ Ecuador e regioni vicine. VII. Onicofori. Bollettino dei Musei di Zoologia ed Anatomia comparata della R. Universita di Torino 13: 1-3. https://doi.org/10.5962/bhlI.part. 16811 Chagas-Junior A, Costa CS (2014) Macroperipatus ohausi: Redescrip- tion and taxonomic notes on its status (Onychophora, Peripatidae). Revista de Biologia Tropical 62: 977-985. https://doi.org/10.15517/ rbt.v6213.11643 Cisneros-Heredia DF (2003) Herpetofauna de la Estacion de Biodiver- sidad Tiputini, Amazonia Ecuatoriana. In: Memorias del I Congreso de Ecologia y Ambiente, Ecuador pais megadiverso. Universidad San Francisco de Quito USFQ, Quito, 21. Cisneros-Heredia DF (2006) Turtles of the Tiputini Biodiversity Sta- tion with remarks on the diversity and distribution of the Testudines from Ecuador. Biota Neotropica 6. https://doi.org/10.1590/S1676- 06032006000100011 Clark AH (1913) A revision of the American species of Peripatus. Pro- ceedings of the Biological Society of Washington 16: 15—20. Clark AH (1914a) Notes on Some Specimens of a Species of Onycho- phore (Oroperipatus corradoi) New to the Fauna of Panama. Smith- sonian Miscellaneous Collections 63: 1-2. zse.pensoft.net Montalvo-Salazar, J.L. et al.: New Oroperipatus from western Amazonia Clark AH (1914b) On some onychophores (Peripatus) from the Repub- lic of. Panama. Zoologischer Anzeiger 45: 145-146. Clark AH, Zetek J (1946) The onychophores of Panama and the Ca- nal Zone. Proceedings of the United States National Museum 96: 205-213. https://doi.org/10.5479/si.00963801.96-3197.205 Cockerell TDA (1908) Monographie des Onychophores. By E. L. Bouvier. Extracted from Annales de Sciences Naturelles, Zoologie (1907), pp. 383 + 318, Pls. XHI. Science 27: 619-621. https://do1. org/10.1126/science.27.694.619 Contreras-Félix GA, Montiel-Parra G, Cupul-Magafia FG, Pérez TM (2018) Redescription of the velvet worm Oroperipatus eisenii (On- ychophora, Peripatidae), through DNA sequencing, scanning elec- tron microscopy and new collection records from Western Mexico. Revista Mexicana de Biodiversidad 89. https://doi.org/10.22201/ 1b.20078706e.2018.4.2586 Correoso Rodriguez M (2011) Nueva localidad de Oroperipatus quiten- sis (Peripatidae-Onychophora) en el Ecuador, consideraciones bio- geograficas. Revista Geoespacial 8: 23-33. Costa CS, Giribet G (2021) Panamanian velvet worms in the genus Epiperipatus, with notes on their taxonomy and distribution and the description of a new species (Onychophora, Peripatidae). Inverte- brate Biology 12. https://do1.org/10.1111/ivb. 12336 Costa CS, Chagas-Junior A, Pinto-da-Rocha R (2018) Redescription of Epiperipatus edwardsii, and descriptions of five new species of Epiperipatus from Brazil (Onychophora, Peripatidae). Zoologia 35: e23366. https://doi.org/10.3897/zoologia.35.e23366 Costa CS, Giribet G, Pinto-Da-Rocha R (2021) Morphological and molecular phylogeny of Epiperipatus (Onychophora: Peripatidae): a combined approach. Zoological Journal of the Linnean Society 192(3): 763-793. https://doi.org/10.1093/zoolinnean/zlaa100 Fuhrmann O (1915) Uber eine neue Peripatus-Art vom Oberlauf des Amazonas. Abhandlungen der Senckenbergischen Naturforschen- den Gesellschaft 36: 275-283. Greshake B (2017) Looking into Pandora’s Box: The Content of Sci- Hub and its Usage. F1000 Research 6: 541. https://doi.org/10.12688/ f1000research.11366.1 Giribet G, Buckman- Young RS, Costa CS, Baker CM, Benavides LR, Branstetter MG, Daniels SR, Pinto-da-Rocha R (2018) The ‘Peri- patos’ in Eurogondwana? — Lack of evidence that southeast Asian onychophorans walked through Europe. Invertebrate Systematics 32: 842. https://doi.org/10.1071/IS18007 Himmelstein DS, Romero AR, Levernier JG, Munro TA, McLaughlin SR, Greshake B, Greene CS (2018) Sci-Hub provides access to near- ly all scholarly literature. eLife 7: e32822. https://doi.org/10.7554/ eLife.32822 Icochea J, Ramirez Ri (1996) Nota sobre los Onychophora del Peru. Revista Peruana de Entomologia 39: 17-18. ICZN (1999) International Code of Zoological Nomenclature. 4" edi- tion. International Trust for Zoological Nomenclature, London. https://www.iczn.org/the-code/the-code-online/ Mayer G, Franke FA, Treffkorn S, Gross V, de Sena Oliveira I (2015) Onychophora. In: Wanninger A (Ed.) Evolutionary Developmental Biology of Invertebrates 3: Ecdysozoa I: Non-Tetraconata. Springer, Vienna, 53-98. https://do1.org/10.1007/978-3-709 1-1865-8 4 Monge-Najera J (1994) Reproductive trends, habitat type and body characteristics in velvet worms (Onychophora). Revista de Biologia Tropical 42: 611-622. Zoosyst. Evol. 100 (3) 2024, 779-789 Monge-Najera J (1995) Phylogeny, biogeography and reproductive trends in the Onychophora. Zoological Journal of the Linnean Soci- ety 114: 21-60. https://doi.org/10.1006/zjls.1995.0015 Morera-Brenes B, Najera JM (2010) A new giant species of placent- ed worm and the mechanism by which onychophorans weave their nets (Onychophora, Peripatidae). Revista de Biologia Tropical 58: 1127-1142. https://doi.org/10.15517/rbt.v5814.5398 Oliveira IDS (2023) An updated world checklist of velvet worms (On- ychophora) with notes on nomenclature and status of names. Zoo- Keys 1184: 133-260. https://doi.org/10.3897/zookeys.1184.107286 Oliveira IDS, Wieloch AH, Mayer G (2010) Revised taxonomy and re- description of two species of the Peripatidae (Onychophora) from Brazil: A step towards consistent terminology of morphological characters. Zootaxa 2493: 16-34. https://doi.org/10.11646/zoot- axa.2493.1.2 Oliveira I de S, Schaffer S, Kvartalnov PV, Galoyan EA, Palko IV, Weck-Heimann A, Geissler P, Ruhberg H, Mayer G (2013) A new species of Eoperipatus (Onychophora) from Vietnam reveals nov- el morphological characters for the South-East Asian Peripatidae. Zoologischer Anzeiger 252: 495-510. https://doi.org/10.1016/j. jez.2013.01.001 Oliveira IDS, Franke FA, Hering L, Schaffer S, Rowell DM, Weck-Hei- mann A, Monge-Najera J, Morera-Brenes B, Mayer G (2012) Un- explored Character Diversity in Onychophora (Velvet Worms): A Comparative Study of Three Peripatid Species. PLoS ONE 7: e51220. https://doi.org/10.1371/journal.pone.0051220 Paynter RA (1993) Ornithological gazetteer of Ecuador. 2" ed. Museum of Comparative Zoology, Harvard University, Cambridge, Mass., 268 pp. https://doi.org/10.5962/bhI.title. 14626 Pripnow B, Ruhberg H (2003) Peripatopsidae (Onychophora) from New Zealand — observations on selected morphs of the *Peripatoi- des novaezealandiae-complex’ in culture: Morphological and re- productive aspects. African Invertebrates 44: 103-114. https://hdl. handle.net/10520/EJC84511 789 Read VMSTJ (1988) The application of scanning electron microsco- py to the systematics of the neotropical Peripatidae (Onychophora). Zoological Journal of the Linnean Society 93: 187—223. https://doi. org/10.1111/j.1096-3642. 1988 .tb01361.x Reyes-Puig C, Wake DB, Kotharambath R, Streicher JW, Koch C, Cis- neros-Heredia DF, Yanez-Mufioz MH, Ron S (2020) Two extreme- ly rare new species of fossorial salamanders of the genus Oedip- ina (Plethodontidae) from northwestern Ecuador. PeerJ 8: e9934. https://doi.org/10.7717/peer).9934 Ribera C (1977) Sobre Peripatus corradoi L. Camerano 1898. Mis- cel-lania. Zoologica 4: 57-59. Romo D, Mosquera D, Swing K, di Fiore A, Blake JG, Loiselle BA, Ry- der TB, de la Torre S, Erwin TL, Pitman NCA, Cisneros-Heredia D, Voigt CC, Burnham RJ, Alvarez H, Vinueza G, Abondano L, Alvarez S, Bruna EM, Duries R, Ellis K, Fernandez E, Ghanem SJ, Guerra J, Hidalgo J, Jenkins CN, Link A, Maehr E, Paniagua F, Porter A, Rodri- guez M, Schmidtt C, Seales L, Snowdon C, Stocks G, Tori WP, Wid- mer J, Yépez P, Zamorano L (2017) Los secretos del Yasuni: Avances en investigacion en la Estacién de Biodiversidad Tiputini, Universi- dad San Francisco de Quito USFQ. USFQ PRESS, Quito, 356 pp. Ruhberg H, Daniels SR (2013) Morphological assessment supports the recognition of four novel species in the widely distributed velvet worm Peripatopsis moseleyi sensu lato (Onychophora, Peripa- topsidae). Invertebrate Systematics 27(2): 131-145. https://doi. org/10.1071/1S12069 Ryder TB, Sillett TS (2016) Climate, demography and lek stability in an Amazonian bird. Proceedings. Biological Sciences 283: 20152314. https://doi.org/10.1098/rspb.2015.2314 Sampaio-Costa C, Chagas-Junior A, Baptista RLC (2009) Brazilian species of Onychophora with notes on their taxonomy and dis- tribution. Zoologia 26: 553-561. https://doi.org/10.1590/S1984- 46702009005000004 Schmarda LK (1871) 2 Zoologie. Volume 1. Wilhelm Braumiiller K. K. Hof- und Universitatsbuchhandler, Vienna, 372 pp. zse.pensoft.net