Marcos Ryotaro Hara

Comparative study of the defensive behavior and morphology of the gland opening area among harvestmen (Arachnida, Opiliones, Gonyleptidae) under a phylogenetic perspective

The arachnids of the order Opiliones (harvestmen) have a pair of scent glands opening at the sides of the body, the substances of which are used in defense. Several types of behavioral, morphological and chemical defensive mechanisms have been assigned to the order as a whole, although some of these tactics were restricted to particular groups. Only around 25 species have been studied from this perspective so far. In the present paper, we analyzed 33 species (mostly from the largest harvestmen family, the Gonyleptidae) aiming at recognizing the usefulness of the defensive characters in taxonomy and evolutionary biology. We observed the morphology of the gland opening (ozopore) area and the defensive behavior, and their relationship, and mapped these traits on an available phylogenetic hypothesis of relationship within Gonyleptidae. As outgroups, we analyzed Cosmetidae and Stygnidae. Combining the observed behavioral characters of the emission of defensive secretion (near the ozopore, with liquid displacement through an integumentary groove, or in form of a jet) with the morphological types of the gland opening (direction of the integumentary dome that surrounds the gland opening, presence of two openings and the relationship between their sizes, and presence of a V-shaped cut at the anterior opening), we recognized eight patterns. In addition, we could examine the evolution of such traits within Gonyleptidae.

New systematic assignments in Gonyleptoidea (Arachnida, Opiliones, Laniatores)

Abstract As part of an ongoing revision of the family Gonyleptidae, we have identified many species that are synonyms of previously described species or misplaced in this family. This article summarizes these findings, adding previously unavailable information or correcting imprecise observations to justify the presented taxonomic changes. The following new familial or subfamilial assignments are proposed: Nemastygnus Roewer, 1929 and Taulisa Roewer, 1956 are transferred to Agoristenidae, Agoristeninae; Napostygnus Roewer, 1929 to Cranaidae; Ceropachylinus peruvianus Roewer, 1956 and Pirunipygus Roewer, 1936 are transferred to Gonyleptidae, Ampycinae; Gyndesops Roewer, 1943, Haversia Roewer, 1913 and Oxapampeus Roewer, 1963 are transferred to Gonyleptidae, Pachylinae. The following generic synonymies are proposed for the family Gonyleptidae: Acanthogonyleptes Mello-Leitão, 1922 = Centroleptes Roewer, 1943; Acrographinotus Roewer, 1929 = Unduavius Roewer, 1929; Gonyleptes Kirby, 1819 = Collonychium Bertkau, 1880; Mischonyx Bertkau, 1880 = Eugonyleptes Roewer, 1913 and Gonazula Roewer, 1930; Parampheres Roewer, 1913 = Metapachyloides Roewer, 1917; Pseudopucrolia Roewer, 1912 = Meteusarcus Roewer, 1913; Haversia Roewer, 1913 = Hoggellula Roewer, 1930. The following specific synonymies are proposed for the family Gonyleptidae: Acanthogonyleptes singularis (Mello-Leitão, 1935) = Centroleptes flavus Roewer, 1943, syn. n.; Geraeocormobius sylvarum Holmberg, 1887 = Discocyrtus serrifemur Roewer, 1943, syn. n.; Gonyleptellus bimaculatus (Sørensen, 1884) = Gonyleptes cancellatus Roewer,1917, syn. n.; Gonyleptes atrus Mello-Leitão, 1923 = Weyhia brieni Giltay, 1928, syn. n.; Gonyleptes fragilis Mello-Leitão, 1923 = Gonyleptes banana Kury, 2003, syn. n.; Gonyleptes horridus Kirby, 1819 = Collonychium bicuspidatum Bertkau, 1880, syn. n., Gonyleptes borgmeyeri Mello-Leitão, 1932, syn. n., Gonyleptes curvicornis Mello-Leitão, 1932, syn. n., Metagonyleptes hamatus Roewer, 1913, syn. n. and Paragonyleptes simoni Roewer, 1930, syn. n.; Gonyleptes pustulatus Sørensen, 1884 = Gonyleptes guttatus Roewer, 1917, syn. n.; Haversia defensa (Butler, 1876) = Sadocus vallentini Hogg, 1913, syn. n.; Liogonyleptoides minensis (Piza, 1946) = Currala bahiensis Soares, 1972, syn. n.; Megapachylus grandis Roewer, 1913 = Metapachyloides almeidai Soares & Soares, 1946, syn. n.; Mischonyx cuspidatus (Roewer, 1913) = Gonazula gibbosa Roewer, 1930 syn. n.; Mischonyx scaber (Kirby, 1819) = Xundarava holacantha Mello-Leitão, 1927, syn. n.; Parampheres tibialis Roewer, 1917 = Metapachyloides rugosus Roewer, 1917, syn. n.; Parapachyloides uncinatus (Sørensen, 1879) = Goyazella armata Mello-Leitão, 1931, syn. n.; Pseudopucrolia mutica (Perty, 1833) = Meteusarcus armatus Roewer, 1913, syn. n. The following new combinations are proposed: Acrographinotus ornatus (Roewer, 1929), comb. n. (ex Unduavius); Gonyleptellus bimaculatus (Sørensen, 1884),comb. n. (ex Gonyleptes);Gonyleptes perlatus (Mello-Leitão, 1935), comb. n. (exMoojenia);Mischonyx scaber (Kirby, 1819), comb. n. (ex Gonyleptes); and Neopachyloides peruvianus (Roewer, 1956), comb. n. (ex Ceropachylus). The following species of Gonyleptidae, Gonyleptinae are revalidated: Gonyleptes atrus Mello-Leitão, 1923 and Gonyleptes curvicornis (Roewer, 1913).

MALE EGG GUARDING BEHAVIOR IN THE NEOTROPICAL HARVESTMAN AMPHERES LEUCOPHEUS (MELLO-LEITÃO 1922) (OPILIONES, GONYLEPTIDAE)

Abstract Males of the Neotropical harvestman Ampheres leucopheus (Mello-Leitão 1922) were observed guarding egg-batches attached to the undersurface of leaves. As recorded for other paternal harvestmen, males of A. leucopheus guard egg-batches containing eggs in different developmental stages as well as newly hatched nymphs. This is the second case of paternal care recorded among gonyleptids and the fifth in the order Opiliones.

Redescription of Platygyndes Roewer 1943, a false Gonyleptidae, (Arachnida, Opiliones, Cosmetidae)

Abstract Praelibitia Roewer, 1956 and its type species, Praelibitia titicaca Roewer, 1956, are respectively synonymized with Platygyndes Roewer, 1943 and its type species Platygyndes titicaca Roewer, 1943, and furthermore the genus is transferred from the Gonyleptidae to the Cosmetidae. On the basis of domed and unarmed ocularium, increased number of granules on scutal areas, unarmed dorsal scutum and general body shape, Platygyndes seems to be closely related to Moselabius Roewer, 1956 and Caracarana Roewer, 1956. External morphological characters that are useful to revealing relationships among cosmetid genera are discussed.

A new species and new distribution records of Pickeliana (Opiliones: Laniatores: Stygnidae)

A new species of Pickeliana Mello-Leitao, 1932, P. albimaculata sp. nov., is described from Jussari, Bahia, Brazil. It can be easily distinguished from the already described species by the presence of white spots on mesotergal area I and anal opercle. It is similar to P. pickeli Mello-Leitao, 1932 by the presence of a large, ventro-apical pointed tubercle on femora III-IV. A cladistic analysis was performed adding a new character to the available character matrix, the presence of a large and ventro-apical pointed tubercle on male femur IV. According to this analysis, P. albimaculata sp. nov. is sister species of P. pickeli. Additionally, we present an identification key and an update on the geographical distribution of species of this genus in northeastern Brazil.

Intense leg tapping behavior by the harvestman Mischonyx cuspidatus (Gonyleptidae): an undescribed defensive behavior in Opiliones?

Abstract We describe for the first time the behavior “Intense Leg Tapping (ILT)” being used in a prey-predator context between the Neotropical harvestman Mischonyx cuspidatus (Roewer 1913) and the syntopic spider Ctenus ornatus (Keyserling 1877). Previously, the harvestmans repeated fast dorsoventral movements of legs II had only been described during conspecific male-male interactions. We suggest it has a defensive function.

Revision of the cranaid genera Phalangodus, Iquitosa and Aguaytiella (Opiliones: Laniatores: Gonyleptoidea)

The monotypic genus Temucus Roewer, 1943, originally placed in Pachylinae (Gonyleptidae) is transferred to the Cranainae (Cranaidae) and synonymized with Phalangodus Gervais, 1842, therefore Phalangodus palpiconus (Roewer, 1943) comb. nov. is proposed. The synonymy is based on the following features: (i) the outline of dorsal scutum type alpha; (ii) the thickened pedipalpal claw in males; (iii) pedipalpal femur with a few ventral enlarged tubercles restricted to the median ventral region, and a conspicuous group of very large and acuminated tubercles basally; (iv) ventral plate of penis with a rather elevated number of cylindrical, straight and sharp distal pairs of setae and a notorious reduction in the number of the basal pairs of setae; (v) penis stylus straight, its distal tip rounded in a mushroom-like shape without stylar caps. The record of P. palpiconus to Chile is doubtful. We also propose the revalidation of Iquitosa Roewer, 1943, hitherto considered a junior synonym of Phalangodus. Iquitosa is revised and the male of its type species, I. poecilis, is reported for the first time. Aguaytiella Goodnight & Goodnight, 1943, a monotypic genus which superficially resembles Iquitosa is also revised. In this article, we report data of male genitalia of Iquitosa and Aguaytiella, providing redescriptions and diagnoses of those genera and species, and a discussion of their relationship with other cranaids.

The Scent Glands of the Neotropical Harvestman Discocyrtus pectnifemur: Morphology, Behavior and Chemistry

Harvestmen have a pair of scent glands that open through ozopores. The literature suggests a link between the morphology of the ozopore area and the emission of a defensive secretion. A previous study on a species that aggregates in open areas, where individuals are probably more easily spotted by predators, showed that this defensive secretion causes conspecifics to flee. However, it is unknown whether this behavior occurs in species that aggregate in sheltered areas, where prey are harder to find. Herein, we describe the morphology of the ozopore area, the mode of emission of the defensive secretion, and its chemical composition in the harvestman Discocyrtus pectinifemur. We also tested if the defensive secretion is used as an alarm pheromone. We found that D. pectinifemur releases the defensive secretion in different ways, one of them being as a jet. Emission as a jet contrasts with that known for all congeners previously studied, and is in accord with the expected morphology of the ozopore. We found that the defensive secretion of D. pectinifemur does not function as an alarm pheromone. The composition of the defensive secretion, a mixture of quinones, is congruent with those already described for the clade that includes Discocyrtus. Our results support the link between the morphology of the scent glands area and the emission behavior of the defensive secretion, and they suggest that the alarm pheromone function in harvestmen may be dependent on ecological factors.

Cladistic analysis and description of three new species of the Chilean genus Nanophareus (Opiliones: Gonyleptidae: Pachylinae)

Three new species of the Chilean Pachylinae genus, Nanophareus Roewer, 1929 are described: N. bicornutus sp. nov. (Valle de Aconcagua, Zapallar, V Región de Valparaíso), N. maipu sp. nov. (La Rinconada, Quebrada de la Plata, Maipu, Región Metropolitana-Santiago), and N. polyhastatus sp. nov. (El Abanico, VIII Región de Bio-Bío). These three new species were included in a cladistic analysis that resulted in two equally most parsimonious trees (238 steps, C.I. = 0.38; R.I. = 0.51), corroborating the monophyly of Nanophareus. The proposed synapomorphies for Nanophareus remain largely unchanged: an external row of enlarged tubercles inserted amongst small ones on the lateral margin of dorsal scutum; the ventro-basal margin of the pedipalpal tibia curved at 90° in lateral view; and retrolateral seta on pedipalpal tibia with an apically bifid socket (socket and seta longer than pedipalpal tibia length), with additional small setae distally. The sister group of Nanophareus, as well as its subfamilial placement, are still unsettled issues that are here further discussed.

Revision of the South American Fonckia (Opiliones: Gonyleptidae: Pachylinae) with the description of two new species

Fonckia Roewer, 1913 is revised and two new species are described in it: Fonckia contulmo sp. nov., from Monumento Nacional Contulmo, Araucania, Chile, diagnosed mainly by the enlarged tubercles on the lateral margins of the dorsal scutum, between the median region of scutal area II and the posterior margin of the scutal area III; and Fonckia sosia sp. nov., from Parque Nacional Conguillio, Malleco, Chile, distinguished mainly by the absence of a dorso-basal apophysis on femur IV of the male and a spiniform, enlarged retroapical tubercle on tibia IV of the male. We propose the generic synonymy of Diconospelta Canals, 1934 under Fonckia Roewer, 1913, and the specific synonymy of D. vazferreirae Mello-Leitao, 1946 under F. processigera (Sorensen, 1902). We also propose the new combination F. gallardoi (Canals, 1934) comb. nov. As a consequence, the genus is henceforth composed of four species. We present an identification key for the species of Fonckia, as well as diagnoses and a discussion of the Chilean Pachylinae.