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

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.     

Ontogenetic variation in the sensory structures on the pedipalps of cosmetid harvestmen (Arachnida,Opiliones, Laniatores)

In arachnids, pedipalps are highly variable appendages that may be used in feeding, courtship, defense, and agonistic encounters. In cosmetid harvestmen, adults have pedipalps that feature flattened femora, spoon‐shaped tibiae, and robust tarsal claws. In contrast, the pedipalps of nymphs are elongate with cylindrical podomeres and are adorned with delicate pretarsi. In this study, we used scanning electron microscopy to examine the distribution of cuticular structures (e.g., sensilla chaetica, pores) on the elements of the pedipalps of adults and nymphs of three species of cosmetid harvestmen. Our results indicate that there is considerable ontogenetic variation in the morphology of the trochanter, femur, patella, tibia, and tarsus. The pretarsus of the nymph has a ventral patch of setae that is absent from the adult tarsal claw. We observed this structure on all three cosmetid species as well as on the pedipalps of an additional seven morphospecies of nymphs collected in Belize and Costa Rica. This structure may represent a previously unrecognized autapomorphy for Cosmetidae. Examinations of the pedipalps of antepenultimate nymphs of additional gonyleptoidean harvestmen representing the families Ampycidae, Cranaidae, Manaosbiidae, and Stygnidae revealed the occurrence of unusual, plumose tarsal setae, but no setal patches on the tarsal claw.     

Interspecific,ontogenetic, and sexual variation in ozopore morphology among cosmetid harvestmen (Arachnida,Opiliones, Laniatores)

The ozopores of cosmetid harvestmen rest upon lateral projections of the carapace, have simple or highly reduced channels, and are partially obscured by enlarged dorsal processes associated with coxae I and II. Rather than use scent gland secretions to form a chemical shield on the dorsum, the cosmetid harvestman exhibits a unique defensive behavior known as “leg dabbing” in which the distal tip of tarsus I or II is dipped into fluid that accumulate at the base of coxa II and the droplet on the tarsus is pointed toward the predator. Relatively little is known about interspecific variation in ozopore morphology among cosmetid harvestmen. In this study, we used scanning electron microscopy to examine the ozopores of males and females of nine species as well as those of antepenultimate nymphs for two species. Among adults, we found differences between species in the shapes of the ozopores (round or subtriangular), the morphology of the dorsal and lateral channels (if present), and the relative size, shape and armature of the dorsal posterior process (dpp) of coxa I and the dorsal anterior process (dap) of coxa II. Our observations suggest that the morphology of dpp I and dap II could be sources for systematic characters in future phylogenetic studies of the Cosmetidae. We observed ontogenetic differences but relatively little intersexual variation in the morphology of the ozopore. The ozopores of nymphs are generally more oval than those of adults and the opening of the ozopore of the nymph is less obstructed, if at all, by the dorsal coxal processes of legs I–II. These morphological differences suggest that nymphs may use scent gland secretions in a manner different from that of adults.     

Interspecific variation in ovipositor morphology among Manaosbiid and Nomoclastid Harvestmen (Arachnida,Opiliones, Laniatores)

The external anatomy of the ovipositor has generally been overlooked as a source of informative characters in systematic studies of laniatorean harvestmen. In this study, we used scanning electron microscopy to examine the ovipositors of nine species representing the families Manaosbiidae (five species) and Nomoclastidae (four species). Similar to the ovipositor morphology of many gonyleptoidean families, the distal tips of the ovipositors of these harvestmen have four external lobes, with the margins most commonly adorned with 10 large peripheral setae. In manaosbiid and nomoclastid species, these peripheral setae have undivided bases, striated shafts and undivided distal tips. There are typically three setae on each anterior lobe and two setae on each posterior lobe. The medial setae on both anterior and posterior lobes insert into sockets that are slightly more dorsal. We observed small, surface denticles, usually associated with a pore, on the external surface of the lobes. There was interspecific and intraspecific variation in the number and shape of these surface denticles. The association of pores with denticles on the ovipositor appears to be a feature common to not only both families but is also a trait that has not been observed on ovipositors in other families of laniatorean harvestmen.     

Comparative study of the morphology of the gland opening area among Grassatores harvestmen (Arachnida,Opiliones, Laniatores)

Arachnids of the order Opiliones (harvestmen), which includes around 6000 specìes, have a pair of scent glands that open at the sides of the body, producing substances used as defence. Several types of behavioural, morphological and chemical defensive mechanisms have been identified in the order as a whole, although some of these tactics were restricted to particular groups. Only around 60 species have been studied from this perspective so far, more than half of which belong to the largest harvestman family within the order Laniatores, the Gonyleptidae, and have only recently been studied in an evolutionary perspective, showing the usefulness of defensive characters in taxonomy and evolutionary biology. Within Laniatores, the Grassatores clade includes the Gonyleptidae and 20 additional families, mostly poorly or not previously studied. We describe the morphology of the structures involved in fluid displacement during chemical defence in 15 of these families (data on two additional families are available from the literature) and discuss the evolution of such traits based on an available phylogenetic hypothesis of relationships within Grassatores, using the representatives of Triaenonychidae (a non‐Grassatores family of Laniatores) for comparison. We conclude that most non‐gonyleptoid Grassatores share (maybe plesiomorphically) a series of characteristics, mostly strongly different from what is observed within the gonyleptoids, and that smaller groups seem to share diagnostic features related to chemical defence, as is the case of stygnids, cosmetids and triaenonychines, and especially of manaosbiids and cranaids, whose defensive morphologies largely resemble those of derived gonyleptids. The following main synapomorphies were detected: (a) Grassatores: the presence of a deep and well‐defined descending channel; (b) Samooidea+Zalmoxoidea+Assamioidea+Gonyleptoidea: lateral pegs along the lateral channel; (c) Samooidea+Zalmoxoidea: deep channels forming an H on the dorsal scute; (d) Gonyleptoidea: ozopore cutting dorsally (reversing in Agoristenidae and Stygnidae to a laterally placed oval ozopore), a wide and smooth lateral channel, reversing to a lateral channel whose bottom is covered with either small plates (Agoristenidae) or high tubercles (Stygnidae), and apophyses of coxa II close to or covering the ozopore.     

Leg injuries and wound repair among cosmetid harvestmen (Arachnida,Opiliones, Laniatores)

Previous studies of leg injuries in harvestmen have focused on the fitness consequences for individuals that use autospasy (voluntary detachment of the leg) as a secondary defense mechanism. Leg damage among non‐autotomizing species of laniatorean harvestmen has not been investigated. Under laboratory conditions, we damaged femur IV of Cynorta marginalis and observed with scanning electron microscopy (SEM) the changes in these wounds over ten days. We also used SEM to examine leg damage from individuals of three species of cosmetid harvestmen that were collected in the field. On the basis of changes in the external surface of the hemolymph coagulum, we classified these wounds as fresh (coagulum forming), recent (coagulum with smooth surface), older (coagulum is scale‐like with visible cell fragments), and fully healed (scale replaced by new cuticle growth on the terminal stump). Our observations indicate that wound healing in harvestmen occurs in a manner comparable to that of other chelicerates. Leg injuries exhibited interspecific variation with respect to the overall frequency of leg wounds and the specific legs that were most commonly damaged. In addition, we measured walking and climbing speeds of adult C . marginalis and found that individuals with fresh injuries (lab‐induced) to femur IV walked at speeds significantly slower than uninjured adults or individuals collected from the field that had fully healed wounds to a single leg. J. Morphol. 278:73–88, 2017. ©© 2016 Wiley Periodicals,Inc.     

A new species of Discocyrtanus from Mato Grosso,Brazil (Opiliones: Gonyleptidae) with a key to the species of the genus

Discocyrtanus canjinjim sp. n., belonging to the family Gonyleptidae Sundevall, 1833 is described based on nineteen specimens, eleven adult males and eight adult females, collected in the Vila Bela da Santíssima Trindade, in the State of Mato Grosso, Brazil. This new species represents an endemic component for the harvestmen fauna of Chiquitano Dry Forests terrestrial eco-region, being the most occidental point of distribution of the genus, notably found in the Cerrado and the Atlantic Forest. The new species is characterized by femur IV swollen with the same length of dorsal scutum, trochanter IV with prodorsal distal apophysis as a stout hook not bifurcated, and a unique form of genitalia in the genus. This paper also includes the first identification key to the species of the genus after its revalidation.     

Morphological changes during postembryonic development in two species of neotropical harvestmen (Opiliones,Laniatores, Cranaidae)

Morphological changes during postembryonic development in the Cranaidae are described on the basis of the examination of an incomplete series of larvae, nymphs, and adults of Phareicranaus calcariferus and Santinezia serratotibialis. The life histories of these species are hypothesized to consist of six nymphal stages, featuring the appearance of secondary male sexual characteristics in the antepenultimate nymph (N5). Color and body shape change dramatically during development. Growth rates for nymphs based upon leg measurements were similar for both species. In S. serratotibialis, the greatest increase in leg size occurred from larva to 1st nymph. The tarsomeres of legs I–IV varied by 1–2 segments per leg for each nymph stage, with the number of tarsal segments increased by 1–2 segments at each stage. Adults had nearly twice as many tarsomeres on leg II than other legs. Ontogenetic changes were observed in the armature of the proximal cheliceral segment, ocularium, pedipalp, opisthosoma, distitarsus III and IV, and leg IV. Morphological changes in postembryonic development in cranaid harvestmen are similar to those reported for other Laniatores. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.     

Phylogeny of harvestmen family Gonyleptidae inferred from a multilocus approach (Arachnida: Opiliones)

Gonyleptidae is the second most diverse harvestmen family and the most studied in terms of morphology, behaviour, and ecology. Despite this, few phylogenetic studies have focused on gonyleptids, and those are based on a very limited number of taxa. We addressed this gap by constructing a phylogenetic hypothesis of the family using 101 taxa from all 16 gonyleptid subfamilies and four mitochondrial and nuclear loci (COI, 28S rRNA, 12S rRNA, and 16S rRNA). These were analysed under parsimony and likelihood optimality criteria (and using direct optimization for the former). Relationships among Gonyleptoidea and within each subfamily of Gonyleptidae were largely congruent between parsimony and maximum‐likelihood approaches. Taxonomic actions from our phylogeny include the following: Tricommatidae, new status, is restored as a family; Metasarcidae, new status, is recognized as a family and considered sister to the Cosmetidae; and Cranainae and Manaosbiinae are suggested as members of Gonyleptidae, restoring Roewer's concept of the family. Within Gonyleptidae, the “K92” group—composed of Sodreaninae, Caelopyginae, Hernandariinae, Progonyleptoidellinae, and Gonyleptinae—forms a clade, although the latter two subfamilies are not monophyletic. The genus Parampheres is here transferred to Caelopyginae, and “Multumbo” dimorphicus to Gonyleptinae. Gonyleptidae is characterized by the presence of a ventral process on the penis glans and a bifid apophysis on the male coxa IV. The long‐legged Mitobatinae can be considered monophyletic only if some short‐legged pachylines are included, or if we assume that elongate legs arose twice independently (in the true mitobatine genera and in Longiperna). Pachylinae, the most diverse gonyleptid subfamily, represents several distinct lineages. We further conclude that the traditional use of a small set of morphological characters in the systematics of Gonyleptidae is unable to explain the complex evolution of the family.     

A comparative analysis of the chemical nature of defensive secretions of Gonyleptidae (Arachnida: Opiliones: Laniatores)

The arachnids of the order Opiliones (harvestmen) produce substances used in defense. In the present paper, we analyzed 22 species of Gonyleptidae to explore the use of defensive substances in taxonomy and evolutionary biology. Thirty-seven different compounds were detected, 18 of which were preliminarily identified. These compounds were mapped onto a phylogenetic tree showing the relationships within the Gonyleptidae. Data from Cosmetidae were used as an outgroup. Five ketones and six alkyl phenols were reported for the first time in harvestmen.     

Phylogeny and taxonomic revision of Heteropachylinae (Opiliones: Laniatores: Gonyleptidae)

Heteropachylinae Kury, 1994 is currently considered an early lineage of Gonyleptidae Sundevall, 1833 and includes small harvestmen that occur in the Atlantic Forests, mainly in the Northeast Region of Brazil. The species of Heteropachylinae were spread in different subfamilies until the establishment of the group. As a result of that, until now there were no comparative works on the subfamily in the literature. In this study, the first systematic review for Heteropachylinae was carried out and the first phylogenetic hypothesis for their taxa is proposed, by means of a cladistic approach. A total of 102 morphological characters was coded for 21 terminal taxa: 11 species of Heteropachylinae, two species from the genus Mangaratiba Mello‐Leitão, 1940 (considered as Heteropachylinae before this paper), seven other gonyleptids, and one cosmetid. The data were analysed using heuristic search algorithms, resulting in one most parsimonious tree (280 steps, consistency index = 0.47, retention index = 0.63). A parsimony analysis under implied weights was also performed, resulting in three trees. According to the results, Heteropachylinae is a monophyletic and well‐supported group if Mangaratiba is excluded. This genus should be returned to where it was originally described – Pachylinae. The subfamily distribution is restricted from Ceará to Espírito Santo Brazilian states. Pseudopucrolia Roewer, 1912 is considered a senior synonym of Melloa Roewer, 1930, Thaumatoleptes Roewer, 1930, and Tribunosoma Roewer, 1943. Two species of Heteropachylus Roewer, 1913, Heteropachylus ramphonotus sp. nov. and Heteropachylus gracilis sp. nov. , from Bahia and Espírito Santo Brazilian states, are newly described. Heteropachylus is considered a senior synonym of Chavesincola Soares & Soares, 1946 and Aesotrinoma H. Soares, 1977. A new genus is also described for a new species from Bahia and Espírito Santo Brazilian states, Magnispina neptunus gen. et sp. nov. Lectotypes are designated for the following species: Pseudopucrolia incerta (Mello‐Leitão, 1928) comb. nov. , Pseudopucrolia discrepans (Roewer, 1943) comb.nov. , Pseudopucrolia rugosa (Roewer, 1930) comb. nov. , Heteropachylus inexpectabilis (Soares & Soares, 1946) comb. nov. and Heteropachylus spiniger Roewer, 1913. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 437–483.     

Size and shape interspecific divergence patterns partly reflect phylogeny in an Onthophagus species‐complex (Coleoptera: Scarabaeidae)

Polyphenism has been suggested as an accelerator for morphological evolution and speciation. In the dung beetles of the genus Onthophagus, horn expression is polyphenic: large males develop horns whereas smaller males express greatly reduced or no horns. Horn static allometries seem to diverge rapidly amongst extant taxa, a process which might trigger changes in the male genital morphology, thus possibly promoting speciation as a by‐product. It can therefore be hypothesized that interspecific distances in allometries and, possibly, in other morphological traits mirror phylogenetic distances. In this study we first assessed the phylogenetic relationships amongst three closely related taxa belonging to the so‐called ‘Onthophagus fracticornis‐similis‐opacicollis’ species‐complex by sequencing the mitochondrial gene cytochrome oxidase subunit 1 (cox1). Biomolecular results indicated three independent lineages, the closest relationships being found between Onthophagus similis and Onthophagus opacicollis. Then we assessed the extent to which divergence pattern of horn static allometries and size and shape divergence patterns of one genital (paramere) and two nongenital (head and epipharynx) structures mirrored the phylogenetic relationships. Interspecific divergence patterns of horn static allometries, paramere, and head shape were found to be congruent with the evolutionary relationships inferred from biomolecular data. Nevertheless, paramere size and epipharynx shape showed patterns not consistent with the phylogeny. Furthermore, the relative size of nongenital structures showed little interspecific divergence compared to their shapes. Our results suggest that size and shape interspecific divergence mirror phylogeny only in part; they also indicate that distinct morphological traits may differ in their tendency to evolve in concert, and that size and shape of the same trait can evolve independently across species. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 482–498.     

Assessing the patterns and drivers of shape complexity in the amblypygid pedipalp

Amblypygi is an arachnid order possessing a unique pair of spined pedipalps: appendages that perform in prey capture, courtship, and contest. Pedipalp length, hypothesized to be under sexual selection, varies markedly across amblypygid species, and pedipalp spination, thought to reflect selection for function in prey capture, also differs interspecifically. Differences in pedipalp shape between species may indicate that the relative strength of selection for prey capture and sexual selection vary across the group. However, interspecific differences in pedipalp shape have not been quantified, due to difficulties in identifying homologous features. For the first time, we quantify trends in amblypygid pedipalp shape complexity. We use elliptical Fourier analysis to quantify 2D complexity in pedipalp outlines across eleven species and six genera. We find that complexity significantly decreases as pedipalp length increases. This appears to be driven by relative spine length, suggesting that a trade‐off exists between pedipalp length and spination. Furthermore, significant female‐biased sexual dimorphism in shape complexity is present in the tibial segment of the amblypygid pedipalp. Our results provide novel insights into the drivers of amblypygid pedipalp evolution and suggest that a functional trade‐off between performance in prey capture and other functions under sexual selection exist in this enigmatic structure.     

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.     

Polyphyly of Caddoidea,reinstatement of the family Acropsopilionidae in Dyspnoi,and a revised classification system of Palpatores (Arachnida,Opiliones)

Among the least studied harvestmen are the members of the family Caddidae sensu Shear, 1975 , a group of Opiliones with massive eyes and the putative sister group of the remaining Eupnoi. Caddids were originally described as two families, Caddidae and Acropsopilionidae, but these are currently treated as subfamilies of Caddidae. These minute arachnids are rarely collected and present some interesting biogeographical patterns, including a disjunct distribution between East Asia and eastern North America, and some of the few cases of trans‐Pacific genera in southern hemisphere Opiliones. We therefore obtained samples from most of the landmasses inhabited by Caddidae and undertook a phylogenetic study using nuclear and mitochondrial genes for as many samples as possible. Our results, based on a broad taxonomic sampling, surprisingly showed polyphyly of Caddidae, with the genus Caddo forming the sister group of the remaining Eupnoi, whereas the southern hemisphere genera, many of which were originally placed in Acropsopilionidae, within Dyspnoi, formed the sister clade of the remaining Dyspnoi. In addition, the more recently described genus Hesperopilio, from Western Australia and Chile, was unrelated to either Caddidae or Acropsopilionidae, despite having the supposedly diagnostic large ocularium, and instead appeared deeply nested within the Eupnoi superfamily Phalangioidea. Our results are robust to analytical treatment and to homology scheme (dynamic vs. static notions of homology), resulting in a new phylogenetic proposal for Eupnoi and Dyspnoi. Ancestral state reconstruction suggests that the ancestral Palpatores was probably a tiny harvestman with an enlarged ocularium and glandular palpal setae in its enlarged and armed palps. We take the following taxonomic actions: Acropsopilionidae is removed from synonymy under Caddidae and its family status and membership in Dyspnoi are restored. Hesperopilio Shear, 1996 is removed from Caddoidea/Caddidae and transferred to Phalangioidea, but it is not assigned to any family.     

Temporal,but not spatial,changes in expression patterns of petal identity genes are associated with loss of papillate conical cells and the shift to bird pollination in Macaronesian Lotus (Leguminosae)

• In the generally bee‐pollinated genus Lotus a group of four species have evolved bird‐pollinated flowers. The floral changes in these species include altered petal orientation, shape and texture. In Lotus these characters are associated with dorsiventral petal identity, suggesting that shifts in the expression of dorsal identity genes may be involved in the evolution of bird pollination. Of particular interest is Lotus japonicus CYCLOIDEA 2 (LjCYC2), known to determine the presence of papillate conical cells on the dorsal petal in L. japonicus. Bird‐pollinated species are unusual in not having papillate conical cells on the dorsal petal.
• Using RT‐PCR at various stages of flower development, we determined the timing of expression in all petal types for the three putative petal identity genes (CYC‐like genes) in different species with contrasting floral morphology and pollination syndromes.
• In bird‐pollinated species the dorsal identity gene, LjCYC2, is not expressed at the floral stage when papillate conical cells are normally differentiating in bee‐pollinated species. In contrast, in bee‐pollinated species, LjCYC2 is expressed during conical cell development.
• Changes in the timing of expression of the above two genes are associated with modifications in petal growth and lateralisation of the dorsal and ventral petals in the bird‐pollinated species. This study indicates that changes in the timing, rather than spatial distribution, of expression likely contribute to the modifications of petal micromorphology and petal size during the transition from bee to bird pollination in Macaronesian Lotus species.

     

A NEW BLACKFLY SPECIES OF SIMULIUM (DIPTERA: SIMULIIDAE) FROM GUIZHOU PROVINCE,CHINA*

Abstract The present paper deals with a new species of Simulium (Simulium) from Leigongshan, Guizhou province, S. (S.) qianense sp. nov. The specific name was given in the place of production. On the basis of the morphological characters, the new species (S.) qianense sp. nov evidently falls into S. variegatum species‐group, is most similar to S. (S.) taiwanicum, 1979, but can be distinguished from the latter by the characteristic pattern of scutum and legs color in the both sexes, the shape of male geritalia and several characters in the larva. The type specimens are kept in the Department of Biology of the Guiyang Medical College.