A new Umbopilio species from Assam, NE India (Opiliones: Sclerosomatidae: Gagrellinae)

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1 Zootaxa : (2006) Copyright 2006 Magnolia Press ISSN (print edition) ISSN (online edition) A new Umbopilio species from Assam, NE India (Opiliones: Sclerosomatidae: Gagrellinae) LEOŠ KLIMEŠ Institute of Botany, Academy of Sciences of the Czech Republic, Dukelská 135, Třeboň, Czech Republic. klimes@butbn.cas.cz Abstract The monotypic genus Umbopilio Roewer, 1956 (Opiliones, Sclerosomatidae) from Burma, originally placed in the Phalangiinae and later transferred to the Sclerosomatinae, is here transferred to the Gagrellinae. A second species of the genus, Umbopilio martensi n. sp., is described from Assam, NE India. Key words. Asia, harvestmen, Umbopilio martensi, Umbopilio paradoxus, new species Introduction The family Sclerosomatidae Simon, 1879, with its about 1270 currently known species (Hallan 2005), is the largest family of harvestmen. Of these species, about 950 belong to the subfamily Gagrellinae Thorell, 1889, distributed mainly in the tropics of the Old (700 species) and New World (250 species) (Tourinho-Davis 2004). While a revision of the group has been recently undertaken in S America (Tourinho & Kury 2001, Tourinho-Davis 2004), the only extensive modern study of this group in Asia was carried out in the Nepalese Himalayas (Martens 1987), an area which, even though species-rich, lies at the margin of the distribution area of this group. Roewer (1910, 1923, 1954a, 1954b, 1955a, 1955b), who described numerous taxa of Gagrellinae from SE Asia, did not use genital characters for the delimitation of genera and species. Instead, he used numbers of pseudoarticular nodules on the femora of legs I IV to delimit genera. The usefulness of this character has been repeatedly questioned (Suzuki 1949, 1973; Martens 1987; Tourinho & Kury 2001) as the number of pseudoarticular nodules is variable in some species, pseudoarticular nodules are sometimes difficult to recognise, and the same number of pseudoarticular nodules does not always imply relatedness among species. Consequently, a thorough revision of the subfamily Gagrellinae in Asia, based on a Accepted by Schwendinger: 25 Jul. 2006; published: 28 Sept

2 comprehensive evaluation of all diagnostic characters, including characters of the genital morphology, is needed. Some unexpected difficulties appeared recently also at the level of subfamilies of Sclerosomatidae, after numerous species belonging to the subfamilies Gyantinae and Sclerosomatinae, previously considered to be distributed in Europe (with some extensions to Africa and Asia), were discovered in the Himalayas. These two subfamilies probably originated in Palaearctic Asia (Martens 1973, 1982). As a result of these discoveries, the numbers of characters delimiting Gyantinae, Sclerosomatinae and Gagrellinae have been considerably reduced. Consequently, placement of some species and genera distributed at the verge of the Palaearctic and Oriental regions into subfamilies remains uncertain. For example, the genus Umbopilio Roewer, 1956 was originally placed in the subfamily Phalangiinae. Later, Martens (1973) listed this genus as a representative of Asian Sclerosomatinae. Here I show that this genus belongs to the Gagrellinae, and I describe a new species that I tentatively place in this enigmatic genus. Material and methods Measurements were obtained by means of a binocular Olympus SZ40 microscope equipped with an ocular micrometer, and are rounded to the nearest 0.1 mm. Details and microscopic slides were examined under a compound Meopta microscope equipped with an ocular micrometer. A digital Olympus C-5050 camera attached to a binocular microscope was used to capture images, which were then enlarged and printed. The printed image was then traced and detailed, with repeated reference to the specimen under the binocular microscope. Morphological terms follow Hammen (1985). Acronyms of depositories are: BMNH = The Natural History Museum, London, formerly British Museum (Natural History), UK; Curator: Mrs Janet Becalloni. SMF = Naturmuseum Senckenberg, Frankfurt am Main, Germany; Curator: Dr Peter Jäger. Taxonomy Umbopilio martensi n. sp. Figs 1 8 Type material: Male holotype, BMNH 115, India, Tschima, Naga Hills, Assam. [In] moss from stones and logs [feet]. Evergreen forest. 29 January 1952, coll. T. Clay. Material examined for comparison: Umbopilio paradoxus Roewer, 1956: Male syntype, Burma, (SMF, RII/5792/211 and slides SMF, RII/ ). Etymology: The specific epithet refers to the renowned opilionologist Prof. Jochen Martens, the author of the first successful attempt to divide the Gagrellinae of a larger Magnolia Press KLIMEŠ

3 region into naturally delimited genera. Diagnosis: Ground colour of body pale yellow-cream, with two pairs of brown fuzzy stains between eye mound and posterior margin of prosoma, and with pairs of similar stains on posterior margin of tergites VI and VII. Eye mound with a blunt anterior tubercle. Tergites IX X with a blunt medial tubercle and tergites VIII X with an laterad tubercle near posterior corners on each side (Figs 1 2). Coxae II proximally with pro- and retrolateral tubercles reaching about 1/5 of length of trochanter. Tarsus of pedipalpus clubshaped, tarsal claw with three denticles. Femora and patellae of legs I IV dorso-apically armed with a long dorsad apophysis. Femur I and III incrassate. Pseudoarticular nodules missing on femur, but 3 pseudoarticular nodules present on tibia II. Shaft of penis in proximal half dorso-ventrally flattened. Winglets absent. Description of male holotype: Measurements. Body 2.4 long, prodorsum 1.8 wide, opisthosomal part of dorsal scute 1.6 long and 1.7 wide. Chelicerae: Basal article 0.8 long, in lateral view 0.2 deep in central part; medium article 0.9 long. Pedipalpi: Femur 0.6, patella 0.3, tibia 0.4, tarsus 0.8 long. Penis: 1.0 long. Colour. Pedipalpi yellow-cream, only central half of trochanter and of femur yellowbrown, patella and tibia dorsally and tarsus towards subapical part yellow-brown (Fig. 3). Legs cream-white, except for light brown coxae and femora I, II, and IV (Fig. 7). Ground colour of body pale yellow-cream, with two brown fuzzy stains in central half of posterior margin of tergite V, similar but more widely spaced stains situated on posterior margin of tergite VI. Pairs of dark brown stains on posterior margin of opisthosomal tergites best developed on tergite VII, extending by slightly convergent strips to anterior margin of tergite VII (Figs 1 2). Shaft of penis becoming dark in basal 3/5 (Fig. 5). Cuticle densely glandular. A secretion covering body and trochanter to tibia of pedipalpus and legs. Soil particles and grains of sand firmly attached to secretion. In alcohol-preserved animals secretion forming a semi-lucid layer of scales, these not easily removable without damaging indumentum of body and limbs. Dorsal side. Surface regularly granular (Fig. 2). Supracheliceral laminae armed with two 0.08 long, sparsely setose tubercles (Fig. 2). Anteromedial area of prodorsum slightly elevated. Eye mound 0.2 high, asymmetric in lateral view, with a single blunt anterior tubercle (Fig. 1). Tergites VII VIII slightly depressed submedially. Tergites VII XI with a medial tubercle, this 0.2 high on tergites IX X and considerably lower towards tergites VII and XI. Each of tergites VIII X with a blunt, laterad tubercle near posterior corners on each side (Figs 1 2). Eye mound, medial tubercles on tergites IX and X, and tergite XIII very sparsely setose (Figs 1 2). Odoriferous gland pores not visible, presumably covered by secretion. Ventral side. Surface granular, individual sternites sparsely setose along posterior margins (Fig. 1), individual hairs 0.05 long. Coxae granular, irregularly and sparsely setose, with pro- and retrolateral rows of compressed tubercles. These tubercles bearing a crown of 3 5 spines (Fig. 8). Coxae II proximally with blunt pro- and retrolateral A NEW UMBOPILIO 2006 Magnolia Press 149

4 tubercles densely covered with short hairs, reaching about 1/5 of length of trochanter; similar but smaller prolateral tubercles also on coxa IV (Fig. 2). FIGURES 1 8. Umbopilio martensi n. sp., male holotype. 1 Body, lateral view. 2 Body, dorsal view. 3 Right pedipalpus, prolateral view. 4 Patella and tibia of left pedipalpus, prolateral-ventral view; indumentum not shown. 5 Penis, dorsal view (left), lateral view (right) and cross sections (in between). 6 Right chelicera, retrolateral view. 7 Trochanter, femur, patella, tibia and part of metatarsus of left leg I, retrolateral view. 8 Lateral tubercles on coxa I. Scale line values are in mm Magnolia Press KLIMEŠ

5 FIGURES Umbopilio paradoxus Roewer, 1956, male syntype. 9 Right chelicera, prolateral view. 10 Lateral tubercles on coxa I. 11 Tubercles on supracheliceral laminae, dorsal view. 12 Distal part of tubercles on supracheliceral laminae, dorsal view. 13 Penis, dorsal view (left) and lateral view (right). 14 Distal part of glans penis, dorsal view. Scale line values are in mm. Chelicerae. Ventro-basal hook of basal article terminating in a short spine. Basal article dorsally with several short hairs close to distal end, a few hairs also dorsally on medial article and near articulation of movable finger (Fig. 6). Pedipalpi. All articles unarmed. Femur slightly bent in lateral view; patella with an indistinct distal apophysis (Fig. 4); tarsus markedly club-shaped, in its proximal 1/3 bent dorsally. Patella and tibia densely covered with soft, long hairs, except for smooth ventro-proximal part, femur with a lateral row of short soft hairs, tarsus regularly but sparsely setose. Hairs in apical part of tarsus slightly longer and stiffer than elsewhere on tarsus. Sparse stiff hairs, long, present ventro-distally on trochanter, ventrally on femur, and on all surfaces of patella and tibia except for basal parts. Tarsus ventrally near distal end with a short comb of solenidia. Tarsal claw blunt, with three denticles (Fig. 3). Legs. Femora and patellae I IV dorso-apically with an apophysis directed dorsally, 0.35 and 0.30 long, respectively. All other articles unarmed, their surface granular, in cross section circular or slightly elliptic, without angles, with few hairs in 5 indistinct longitudinal rows. Femora I and III conspicuously incrassate, femur IV less distinctly so, femur II slender. Pseudoarticular nodules on femur I IV missing, but 3 pseudoarticular nodules present on tibia II. Length of individual articles: A NEW UMBOPILIO 2006 Magnolia Press 151

6 Femur Patella Tibia Metatarsus Tarsus Total I II III IV Penis (Fig. 5). Shaft slightly compressed dorso-ventrally, its cross section elliptic in basal half. Ventral side of shaft forming a plate in proximal half. This plate distally extended into a narrowed medial, slightly elevated keel. Lateral sides rounded in basal half of shaft, changing from steeply to gently sloping between medial and distal part. Winglets not developed. Glans elliptic in cross section, smooth, with a pair of subapical setae. Stylus straight. Female: Unknown. Distribution: Known only from the type locality. Discussion Subfamiliar placement of the genus Umbopilio The genus Umbopilio Roewer, 1956 has so far been monotypic. The specific name U. paradoxus Roewer, 1956 seems to refer to a species with an unusual combination of characters: Each of the opisthosomal tergites VIII X with a blunt tubercle near posterior corners on both sides, lobes of leg coxae II forming an obtuse angle in front of operculum genitale, supracheliceral laminae armed with two elongated processes, chelicerae slender, proximal and medial articles unarmed, patella of pedipalpus with an indistinct apophysis, femora of legs I and III incrassate, leg coxae apically deeply depressed (Roewer 1956). The falsely presumed absence of a ventro-basal hook on the basichelicerite, the overlooked denticles on the palpal claw, and the lack of pseudoarticular nodules on the femora of all legs led Roewer (1956) to the erroneous placement of the genus in the Phalangiinae. In his treatment of Himalayan Sclerosomatinae, Martens (1973) listed the genus Umbopilio among the few known Asian genera belonging to this subfamily. The genus Umbopilio differs from the two E Himalayan genera of Sclerosomatinae (Pseudastrobunus Martens, 1973 and Granulosoma Martens, 1973) and also from other Asian members of the subfamily Sclerosomatinae in the following combination of characters: Presence of well-developed lines of lateral tubercles on coxae, odoriferous gland pores well visible, lobes of leg coxae II long, almost touching each other, microsculpture of scutum granular (not brickwall-like), number of denticles on palpal claw low, chelicerae and femur II slender, femur I relatively short and incrassate, pseudoarticular nodules on tibia II present, Magnolia Press KLIMEŠ

7 and tarsus of pedipalpus club-shaped. Some of these characters have been used to delimit Sclerosomatinae from Gagrellinae (Roewer 1910, 1912, 1923; Cokendolpher 1985; Martens 1973, 1987). However, as pointed out by Martens (1973), the delimitation of Sclerosomatinae from Gagrellinae in the E Himalayas is difficult, as several diagnostic characters previously used to differentiate these subfamilies occur together in some species and genera from that region. Most species of Asian Gagrellinae are long-legged, adapted to an arboreal way of life or to walking on stems and leaves of ground vegetation. Their body is dark or colourful, their scutum is often armed with sharp spines, presumably defending the animals from potential predators. However, other, though relatively few, representatives of Gagrellinae are short-legged, cream or brown-cream and have blunt tubercles on opisthosomal tergites, probably being adapted to life in moss and litter (Roewer 1954a, 1954b, 1955a, 1955b; Martens 1987). The number of pseudoarticular nodules on their legs is sometimes reduced or they are missing (as in Himaldroma altus Martens, 1987; Gagrellinae). Still, pseudoarticular nodules can be preserved on leg tibiae (as in Himaldroma pineti Martens, 1987; Gagrellinae). From the border area between the Oriental and Palaearctic regions, Roewer (1935) described several monotypic genera with species sharing these characteristics. Umbopilio paradoxus, Chebabius angulatus Roewer, 1935 and possibly also Umbogrella minuta Roewer, 1954 (Roewer 1955a), all from Burma, are given as examples. The genus Umbopilio shares with Chebabius Roewer, 1935 not only the short femora of legs I, II and IV, but partly also the unusual pattern of dorsal tubercles on the scutum, fused medial tubercles on tergites VII VIII( X) and a laterad tubercle near the posterior corners on each side of tergite(s) (VIII )X. Therefore, I believe that the genus Umbopilio fits better in the subfamily Gagrellinae than in the Sclerosomatinae. This view was also expressed by W. Staręga on an identification label added to the vial with the U. paradoxus type ("Gagrellidae! Verwandtschaftskreis der Gatt. Chebabius Rwr., 1936; 1971, rev. W. Staręga"). Relationships of Umbopilio martensi n. sp. U. paradoxus shares a number of characters with U. martensi n. sp., including long lobes of coxa II perpendicular to the longitudinal axis of the body, anterio-medial area of prodorsum slightly elevated, a tubercle near posterior corners on each side on tergites VIII X (not IX XI as claimed by Roewer; see Roewer 1956: fig. 204), crinkly granular surface of scutum with submedial depression on tergites VII VIII, and elevated medial line or tubercles on tergites VII XI, slender, unarmed chelicerae, unarmed pedipalpus, an indistinct conical apophysis on patella of pedipalpus, club-shaped tarsus of pedipalpus sub-basally slightly bent dorsad, three denticles on palpal claw, scutum covered by a secretion, incrassate femora I and III, slender femur II without pseudoarticular nodules, pseudoarticular nodules on tibia II, coxae II and IV proximally with pro- and retrolateral tubercles, penis without winglets. A NEW UMBOPILIO 2006 Magnolia Press 153

8 Important characters differentiating U. martensi n. sp. from U. paradoxus (in parentheses) are: Ground colour of body pale yellow-cream (dark red-brown). Supracheliceral laminae armed with two hairy, 0.08 long tubercles (tubercles 0.3 long, hairy, with short bristles along medial margin and latero-proximally; Figs 11 12). Eye mound with a blunt anterior tubercle (smooth). Tergites VII XI with a medial tubercle each, the highest tubercles on tergites IX X (medial tubercles inconspicuous). Pro- and retrolateral tubercles on coxae bearing a crown of 3 5 short spines (5 8 longer spines per tubercle; Fig. 10). Coxa II proximally with two blunt pro- and retrolateral tubercles reaching about 1/5 of trochanter length; a smaller pro-lateral tubercle on coxa IV (all coxae proximally with blunt pro- and retrolateral tubercles, slightly constricted at base; tubercles on coxae II III reaching 2/3 of trochanter length). Ventro-basal hook of basichelicerite situated in basal half of article (in basal 1/5 of basichelicerite; Fig. 9). Length/depth of distal cheliceral article in lateral view 4.6 (5.7; Fig. 9). Femora and patellae of legs I IV dorso-apically with an apophysis directed dorsally (dorso-apical apophyses on femora and patellae inconspicuous). Tibia II bearing 3 pseudoarticular nodules (2 pseudoarticular nodules). Ventral side of penis shaft proximally flattened, forming obtuse angle with lateral sides (shaft elliptic in cross section). Glans apically acute (subapically extended; Fig. 14), glans length (excl. stylus)/depth in lateral view 2.3 (4.1; Fig. 13). Genital structures of males have been shown to provide the most reliable and informative characters delimiting genera within Gagrellinae (Martens 1987, Tourinho & Kury 2001). Even if both Umbopilio species lack winglets, which is rare in the subfamily (but see Globulosoma montivaga Martens, 1987 and Metaverpulus kanchensis Martens, 1987), they differ quite substantially in the structure of the penis. On the other hand, Martens (1987) showed that some genera of Gagrellinae share similar genital characters and differ considerably in somatic morphology, whereas in other genera the reverse can be found. The two Umbopilio species undoubtedly share several unusual morphological characters, as listed above, suggesting a relatively close relationship between them. It is also worth considering that the number of monotypic genera of short-legged Gagrellinae from the NW of the Oriental region is very high, so that merging of some genera can be expected to occur in the future. Therefore, I prefer to place the new species in the genus Umbopilio, instead of describing another monotypic genus. The relationships of the genus Umbopilio to other genera of Gagrellinae cannot be established before a thorough revision of the group in SE Asia is carried out. At the moment only resemblance in somatic morphology to the monotypic genus Chebabius Rower 1935, described from Burma, can be pointed out. Acknowledgements This work was financially supported by a DFG project (to Dr Peter Jäger) and by project Magnolia Press KLIMEŠ

9 206/03/1219 of the Grant Agency of the Czech Republic. I am grateful to Mrs Janet Becalloni (BMNH) and Dr Peter Jäger (SMF) for their kind assistance. Dr Peter J. Schwendinger, Prof. Jochen Martens, Dr Nobuo Tsurusaki and Dr Peter Jäger commented on an earlier version of this paper. The English was improved by J. W. Jongepier and by the editors. References Cokendolpher, J.C. (1985) Revision of the harvestman genus Leptobunus and dismantlement of the Leptobunidae (Arachnida: Opiliones: Palpatores). Journal of the New York Entomological Society, 92, Hallan, J. (2005) Synopsis of the described opiliones of the world. 3/7/2005. Available from insects.tamu.edu/research/collection/hallan/acari/opiliones1.htm (accessed April 2006). Hammen, L. van der (1985) Comparative studies in Chelicerata III. Opilionida. Zoologische Verhandelingen, 220, Martens, J. (1973) Opiliones aus dem Nepal-Himalaya. II. Phalangiidae und Sclerosomatidae. Senckenbergiana biologica, 54, Martens, J. (1982) Opiliones aus dem Nepal-Himalaya. V. Gyantinae (Arachnida: Phalangiidae). Senckenbergiana biologica, 62, Martens, J. (1987) Opiliones aus dem Nepal-Himalaya VI. Gagrellinae (Arachnida: Phalangiidae). Courier Forschungsinstitut Senckenberg, 93, Roewer, C.F. (1910) Revision der Opiliones Plagiostethi (= Opiliones Palpatores). I. Teil. Familie der Phalangiidae (Subfamilien: Gagrellini, Liobunini, Leptobunini). Abhandlungen aus dem Gebiete der Naturwissenschaften, herausgegeben vom Naturwissenschaftlichen Verein in Hamburg, 19, Roewer, C.F. (1912) Revision der Opiliones Palpatores (= Opiliones, Plagiostethi). II. Teil. Familie der Phalangiidae (Subfamilien: Sclerosomini, Oligolophini, Phalangiini). Abhandlungen aus dem Gebiete der Naturwissenschaften, herausgegeben vom Naturwissenschaftlichen Verein in Hamburg, 20, Roewer, C.F. (1923) Die Weberknechte der Erde. Systematische Bearbeitung der bisher bekannten Opiliones. Verlag von Gustav Fischer, Jena, 1116 pp. Roewer, C.F. (1935) Südostasiatische Opiliones der Sammlung Fea und Modigliani des Naturhistorischen Museum in Genua. Annali del Museo Civico di Storia Naturale di Genova, 59, Roewer, C.F. (1954a) Indoaustralische Gagrellinae (Opiliones, Arachnidae). (Weitere Weberknechte XVIII.). Part 1. Senckenbergiana biologica 1954, 35, Roewer, C.F. (1954b) Indoaustralische Gagrellinae (Opiliones, Arachnidae). (Weitere Weberknechte XVIII.). Part 2. Senckenbergiana biologica 1954, 35, Roewer, C.F. (1955a) Indoaustralische Gagrellinae (Opiliones, Arachnidae). (Weitere Weberknechte XVIII.). Part 3. Senckenbergiana biologica 1955, 36, Roewer, C.F. (1955a) Indoaustralische Gagrellinae (Opiliones, Arachnidae). (Weitere Weberknechte XVIII.). Part 4. Senckenbergiana biologica 1955, 36, Roewer, C.F. (1956) Über Phalangiinae (Phalangiidae, Opiliones Palpatores). Weitere Weberknechte XIX. Senckenberiana biologica, 37, Suzuki, S. (1949) Studies on the Japanese harvesters. II. Harvesters from Hokkaido, with special reference to variation. Journal of Science of the Hiroshima University, Series B, Division 1 (Zoology), 11, A NEW UMBOPILIO 2006 Magnolia Press 155

10 Suzuki, S (1973) Opiliones from the South-west Islands, Japan. Journal of Science of the Hiroshima University, Series B, Division 1 (Zoology), 24, Tourinho, A.L., Kury, A.B. (2001) Notes on Holcobunus Roewer 1910, with two new generic synonymies (Arachnida, Opiliones, Sclerosomatidae). Boletim do Museu nacional, N. S., Zoologia, 461, Tourinho-Davis, A.L. (2004) A new genus of Gagrellinae from Brazil, with a comparative study of some of the subtropical and southernmost tropical South American genera (Opiliones, Eupnoi, Sclerosomatidae). Revista Ibérica de Aracnología, 9, Magnolia Press KLIMEŠ