94 research outputs found
FIGURE 4 in An integrative taxonomic approach to the identification of three new New Zealand endemic earthworm species (Acanthodrilidae, Octochaetidae: Oligochaeta)
No full textFIGURE 4. Simplified phylogeny of New Zealand earthworms including the three newly described species M. felix, D. gorgon and O. kenleei (NJ tree based on 16S rDNA). The 16S rDNA sequences obtained for the three newly described species were compared to similar sequences obtained by Buckley et al. (2011). One representative for each major clade of New Zealand endemic earthworms was included in the analysis (see Buckley et al. 2011). The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The evolutionary distances were computed using the Maximum Composite Likelihood method (Tamura et al. 2004) and are in the units of the number of base substitutions per site. There were a total of 441 positions in the final dataset.Published as part of Boyer, Stephane, Blakemore, Robert J. & Wratten, Steve D., 2011, An integrative taxonomic approach to the identification of three new New Zealand endemic earthworm species (Acanthodrilidae, Octochaetidae: Oligochaeta), pp. 21-32 in Zootaxa 2994 on page 30, DOI: 10.5281/zenodo.20517
Habitat manipulation to mitigate the impacts of invasive arthropod pests
No full textExotic invaders are some of the most serious insect pests of agricultural crops around the globe. Increasingly, the structure of landscape and habitat is recognized as having a major influence on both insect pests and their natural enemies. Habitat manipulation that aims at conserving natural enemies can potentially contribute to safer and more effective control of invasive pests. In this paper, we review habitat management experiments, published during the last 10 years, which have aimed to improve biological control of invasive pests. We then discuss during what conditions habitat management to conserve natural enemies is likely to be effective and how the likelihood of success of such methods can be improved. We finally suggest an ecologically driven research agenda for habitat management programmes.We acknowledge the following funding sources: the Tertiary Education Commission, New Zealand, through the Bio-Protection Research Centre, Lincoln University, New Zealand (Mattias Jonsson and Steve Wratten), the New Zealand Foundation for Research, Science and Technology (FRST); project LINX0303 (Steve Wratten, Ross Cullen, Jean Tompkins), Lincoln University, New Zealand, for a Post-graduate Scholarship to Jean Tompkins, USDA CSREES Risk Avoidance and Mitigation Program (2004-51101-02210), USDA NC SARE Project (LCN 04-249), USDA CSREES Arthropod and Nematode Biology (2004-35302-14811), North Central Regional IPM, NSF-LTER at Kellogg Biological Station (NSF DEB 0423627), and the Michigan Agricultural Experiment Station (Doug Landis)
Deinodrilus gorgon Blakemore, sp. nov.
No full textDeinodrilus gorgon Blakemore sp. nov. Material examined. Museum of New Zealand Te Papa Tongarewa W.002909 (Holotype). From the tussock grassland of “Happy Valley” (Upper Waimangaroa Valley, Buller Region, West Coast, New Zealand). Collected by S. Boyer, 2010. Mature, posterior amputee, fixed in ethanol 98 % and placed in propylene glycol. Etymology. Noun alluding to Greek mythical monsters with sharp fangs, staring eyes and, similar perhaps to the ring of diverticula on each spermatheca – a belt of serpents. External characters. Body circular in anterior. Pigment dark, especially dorsum with paler setal auriolae; clitellum and male field white. Length 55 + mm with 73 + segments (amputee). Prostomium tanylobous. Setae perichaetine, 12 per segment, evenly spaced. Clitellum pale, tumid ½ 13–16. Dorsal pores from 10 / 11. Nephropores not found. Spermathecal pores in b lines in 7 / 8 and 8 / 9, small but gaping. Female pores anterio-ventral to a setae on 14 in common field. Prostatic pores at b on 17 and 19. Male pores within concave seminal grooves lateral to b. Genital markings as large eye-shaped papillae paired on 10; with smaller markings on 13 rhs, 16 rhs and two additional pairs on 18 as figured. Genital and penial setae not found. Internal morphology. Pharyngeal mass anterior to 4 / 5. Septa 8 / 9–10 / 11 with some thickening. Gizzard muscular in 6 (weak septum 6 / 7 can be carefully teased off to base). Dorsal blood vessel doubled. Heart paired in 10– 13. Nephridia meroic; equatorial forests especially obvious around clitellar segments. Spermathecae in 8 and 9 each with a thin duct to multiple, finger-like diverticula, five per spermatheca (inseminated) surrounding duct from where it thickens before reaching yellowish, knob-like ampulla. Testes free, posterio-ventrally in 10 and 11. Seminal vesicles small saccular in 9 (vestigial?) and larger racemose anterio-dorsally in 11 and 12. Ovaries fan-shaped in 13 with several strings of largish eggs; ovisacs vestigial in 14. Prostates compacted tubular in 17 and 19 exiting through muscular ducts. Vasa deferentia seen to exit unceremoniously in 18. Oesophagus dilated in 15–17 but lacking internal lamellae and thus not construed as calciferous glands. Intestinal origin in 18. Typhlosole thin, lamellar becoming deeper from 19. Gut contains colloidal soil and organic matter. Ecology. Specimen was found under 10 to 20 cm of soil. Dark colouration suggests at least partial surface exposure on topsoil, gut content suggests topsoil geophagy. This species is likely to be anecic. Remarks. Of the eight currently known Deinodrilus species, only two have tanylobous prostomia: D. gracilis Ude, 1905 from Stephen Island and D. parvus Lee, 1959 from Mangamuku Range. Both also have 5 or 6 spermathecal diverticula however, D. gracilis has copulatory setae, oesophageal glands and intestine from 19; while D. parvus has a saddle-shaped clitellum in 12–16, and all its reproductive pores are in a or ab. Further, their gizzards are in 6–7 and 5, respectively, rather than single in 6 as in the current species. D. montanus Lee, 1959 from Rimutaka Range is similar to D. parvus and differs for similar reasons. The current species appears unique in the distribution of its eye-like genital markings that are especially noticeable on segment 10.Published as part of Boyer, Stephane, Blakemore, Robert J. & Wratten, Steve D., 2011, An integrative taxonomic approach to the identification of three new New Zealand endemic earthworm species (Acanthodrilidae, Octochaetidae: Oligochaeta), pp. 21-32 in Zootaxa 2994 on page 24, DOI: 10.5281/zenodo.20517
Weed-insect pollinator networks as bio-indicators of ecological sustainability in agriculture. A review
No full textThe intensification of agricultural practices contributes to the decline of many taxa such as insects and wild plants. Weeds are serious competitors for crop production and are thus controlled. Nonetheless, weeds enhance floral diversity in agricultural landscapes. Weeds provide food for insects in exchange for pollination. The stability of mutualistic interactions in pollination networks depends on conservation of insect pollinator and weed communities. Some agricultural practices can destabilize interactions and thus modify the stability of pollination networks. Therefore, more knowledge on weed-insect networks is needed. Here, we review the interactions involved in insect visits to weed flowers in temperate arable lands. Our main findings are that (1) weed pollination by insects has a key role in maintaining weed communities in arable lands; (2) weed-insect pollinator interactions are modulated by the flowers’ features and their quality which are attracting insects; (3) most weeds are associated with generalist insect pollinators; and (4) even if weed-pollinator networks are largely mutualistic, some antagonist networks can be observed when deception occurs. We propose three weed-insect pollinator networks as potential bio-indicators to evaluate the ecological sustainability of arable land management strategies in temperate areas: (1) Geometridae and Bombyliidae species visiting Caryophyllaceae, (2) Papilionidae foraging on Apiaceae, and (3) Syrphidae visiting Asteraceae
Octochaetus kenleei Blakemore, sp. nov.
No full textOctochaetus kenleei Blakemore sp. nov. Material examined. Museum of New Zealand Te Papa Tongarewa W.002910 (Holotype). From the tussock grassland of “Happy Valley” (Upper Waimangaroa Valley, Buller Region, West Coast, New Zealand). Collected by S. Boyer, 2010. Mature, complete, fixed in ethanol 98 % and placed in propylene glycol. Etymology. In patronymic tribute to the foremost earthworm eco-taxonomist of New Zealand, Dr Kenneth Earnest Lee (1927–2007). External characters. Body circular but posterior slightly square. Pigment lacking and generally fair. Length 220 mm with 270 segments. Prostomium prolobous. Setae lumbricine, 8 per segment, evenly spaced. Clitellum not well marked, perhaps in some or all of 14–20. Dorsal pores from 14 / 15, small. Nephropores not clear, some possibly in c and d lines or rather irregular. Spermathecal pores segmental, lateral to b lines on 8 and 9 on small mounds. Female pores just anterior to setae a on 14. Prostatic pores at b on 17 and 19. Male pores within concave seminal grooves lateral to b. Genital markings as small lens-shaped hollows paired in 8 / 9 and 9 / 10 near b lines and in 15 / 16 in a lines with a unilateral marking in 18 / 19 lhs; area bb in 19 / 20–22 / 23 tumid. Genital and penial setae not found. Internal morphology. Pharyngeal mass anterior to 4 / 5. Septa 8 / 9–10 / 11 with some thickening. Gizzards muscular in 5 and 6. Dorsal blood vessel appears single on gizzards but is doubled from 7 posteriorly. Heart paired in 10–13. Nephridia meroic as a few (ca. 4 per side) small tufted clusters in each segment. Spermathecae in 8 and 9 saccular each with small discrete and interlocular diverticula (inseminated) ringing exit. Testes free, posterio-ventrally in 10 and 11. Seminal vesicles large finely racemose anterio-dorsally in 11 and 12. Ovaries composed of several strings of largish eggs in 13; ovisacs absent. Prostates tubular in 17 and 19 exiting through narrow ducts. Vasa deferentia exits in 18. Oesophagus dilated as annular calciferous gland in 17 with several internal lamellae but not especially vascularized. Intestinal origin in 20 (valval in 19). Typhlosole large inverted T-shape developing from 21. Gut contains colloidal soil with a few quartz grits and woody fragments. Ecology. Specimen was found under 10 to 20 cm of soil. Large size, pale colouration and gut contents suggest subsoil geophagy. This species is likely to be endogeic. Remarks. The current species is compared to Octochaetus thomasi Beddard, 1892, widespread in the Canterbury Plains, that is the only other congener known to have gizzards in 5–6. As with all other members, it has spermathecal pores in 7 / 8 / 9 and on this character alone the current species is differentiated. Neodrilus campestris (Hutton, 1877) from Dunedin has segmental spermathecal pores (on 8) but differs, not least, by qualifying for inclusion in Acanthodrilidae due to its holoic nephridia.Published as part of Boyer, Stephane, Blakemore, Robert J. & Wratten, Steve D., 2011, An integrative taxonomic approach to the identification of three new New Zealand endemic earthworm species (Acanthodrilidae, Octochaetidae: Oligochaeta), pp. 21-32 in Zootaxa 2994 on page 27, DOI: 10.5281/zenodo.20517
Use of sown wildflower strips to enhance natural enemies of agricultural pests
No full textIntensive agriculture and excessive use of agrochemicals have resulted in an impoverished wildlife in agricultural landscapes, especially in arable landscapes but also in perennial high input crops. The elimination of semi-natural habitats, simplification of crop rotations as well as high input of fertilisers and pesticides is considered to be responsible for the severe decline of biological diversity that has been observed (e.g. Aebischer 1991). These practices can reduce habitat quality and remove the necessary habitat structure that is important to many natural enemies.
Moreover, agricultural landscapes are increasingly being simplified; with natural and semi natural areas fragmented and replaced altogether by large monocultural fields. As a consequence, most of the natural enemies depending on such semi-natural habitats for overwintering (Sotherton 1985; Lys and Nentwig 1994; Pfiffner and Luka 2000) need to disperse further to reach summer feeding habitats like agricultural crops. Fragmentation and loss of suitable habitats has caused natural enemies to decline in species diversity and abundance, and has even resulted in extinctions (Fahrig 1997) and loss of biological control functions (Kruess and Tscharntke 1994). Such landscape-scale aspects in biological control are explored in more detail in chapter 4.
Nowadays, a desirable goal in agricultural landscapes is the enhancement of biotic diversity through the use of sustainable farming methods and the conservation and reestablishment of non-crop habitats. Agri-environmental programs have been established in several European countries (e.g. rural development and set-aside programs). Since 1993, the Swiss government has subsidised low-input and sustainable-farming methods (e.g. low-input integrated crop management, organic farming) and the establishment of non-crop habitats. Farmers are encouraged to increase the amount of these non-crop habitats including low-input habitats in order to reverse the observed decline of farmland fauna and to conserve or improve the functions and services of the agroecosystems.
It has been demonstrated that habitat manipulation of the environment can enhance the survival of natural enemies and thereby improve their efficiency as pest-control agents (Gurr et al. 1998; Landis et al. 2000, Nicholls and Altieri, ch. 3 this volume). Field margins are an important type of habitat that provides refuge and resources for many arthropods. Thus field margins play a key role in maintaining biological diversity on farmland (Fry 1994). In addition, it may be useful to combine these semi-natural habitats with low-input agriculture to enhance effects on fauna diversity and natural pest control (Pfiffner 2000; Pfiffner and Luka 2003).
Some habitat manipulation options are known to improve pest control in adjacent production systems. These include grassy beetle banks (Thomas and Marshall 1999; Collins et al. 2002); weedy strips; set-aside strips and field margins (see overview Marshall and Moonen 2002). This chapter focuses on the use of sown wildflower strips (a synonymous term for weed strips) which may be located in field margins. These are used to augment natural enemies and to increase the diversity of flora and fauna in annual and perennial cropping systems.
One of the first initiatives to implement strip farming with sown wildflower strips in practice was taken by Nentwig (1989). Since 1993 this type of field margin has been encouraged and subsidised in the Swiss agri-environmental programs. Nowadays, more than 3000 ha of wildflower strips (in general with a width of 3–10 m) exist on farms all over Switzerland (Anonymous 2003). This chapter will detail how these strips are composed and how they can be established and managed in practice. Finally, their effects on natural enemies and pest control in annual and perennial systems are discussed
Maoridrilus felix Blakemore, sp. nov.
No full textMaoridrilus felix Blakemore sp. nov. Material examined. Museum of New Zealand Te Papa Tongarewa W.002908 (Holotype). From the tussock grassland of ‘Happy Valley’ (Upper Waimangaroa Valley, Buller Region, West Coast, New Zealand). Collected by S. Boyer, 2010. Mature, complete, fixed in ethanol 98 % and placed in propylene glycol. Etymology. Adjectival Latin for “Happy”, after the location name. External characters. Body circular in anterior, squaring off in mid-body and dorsally canaliculate in the posterior 50 or so segments. Pigment dark, especially dorsum chocolate brown with darker mid-dorsal stripe. Length 170 mm with 199 segments. Prostomium tanylobous. Setae lumbricine. Clitellum faintly marked 15-19,½ 20. Dorsal pores wanting. Nephropores, after the first few segments, alternate regularly between c and b lines with anterior segmental distributions: 3–7 c, 8 c or b, 9–10 c, 11 b, 12 c, 13 b, etc. Spermathecal pores in mid-ab lines in 7 / 8 and 8 / 9. Female pores faint, just anterior to b setae on 14. Prostatic pores approximately in a lines on 17 and 19 with protuberant penial setae. Male pores not located within concave seminal grooves, although likely central between retained ab setae. Genital markings absent, but setae ab on 16 with slight pale tumescence as on 20 lhs. Genital setae absent; penial setae longish, curving with spoon-shaped tips [one of their functions, if not primary function, is to scrape out or disrupt any prior semen from spermathecal diverticula that often correspond in depth to the setal length (see Blakemore 2000)]. Internal morphology. Pharyngeal mass anterior to 4 / 5. Septa mostly thin and translucent. Proventriculus wide and S-shaped in 5. Gizzard muscular in 6. Dorsal blood vessel single thoughout. Heart paired in 10–13. Nephridia holoic with long, sausage-shaped vesicles. Spermathecae in 8 and 9 each with a multiloculate diverticulum (inseminated) transcending anterior septum. Testes free, posterio-ventrally in 10 and 11. Seminal vesicles saccular, anterio-dorsally in 11 and 12. Ovaries compact sheets in 13 with large oviducts; ovisacs not found. Prostates tubular in 17 and 19 exiting through muscular ducts with ectal penial setal sheathes and tendons. Vasa deferentia seen to 18. Oesophagus dilated in 11–15 with blood vessels attaching dorsally but not saccular and not construed as calciferous glands. Intestinal origin in 18. Typhlosole not detected to about 26. Gut contains colloidal organic matter. Ecology: Lack of dorsal pores is more usually associated with a semi-aquatic habitat. Unidentified nematodes were found near the prostates (cf. Yeates et al., 1985). Specimen was found under 10 to 20 cm of soil. Dark colouration on the dorsum suggests at least partial surface exposure on topsoil, gut content suggests topsoil geophagy. This species is likely to be anecic. Remarks. Quintessentially Maoridrilus due to its alternating nephridiopores, this species appears unique in its lack of dorsal pores (although more information is needed on several other congeners), gizzard in 6, lack of oesophageal glands, and genital marking absence. Multiloculate spermathecae appear characteristic of the genus and in the current species their form is almost identical to Maoridrilus thomsoni Benham, 1919: fig. 4 from D’Urville Island in Cook Strait. Lee (1959) held this species, along with similar M. intermedius Michaelsen, 1923 and M. mauiensis Benham, 1904, as incertae sedis because original descriptions were inadequate. Permanence of the name M. felix depends on redescription of M. thomsoni, however, the manifestly larger penial setae and lack of oesophageal glands in 14–16 seem to separate the current species. Maoridrilus nelsoni Lee, 1959 differs in its prostatic pores in b lines, and its prominent tuberculae pubertatis ventrally on segments 10 and 16. Maoridrilus uliginosus (Hutton, 1877) differs, not least, in its paired dorsal blood vessel.Published as part of Boyer, Stephane, Blakemore, Robert J. & Wratten, Steve D., 2011, An integrative taxonomic approach to the identification of three new New Zealand endemic earthworm species (Acanthodrilidae, Octochaetidae: Oligochaeta), pp. 21-32 in Zootaxa 2994 on page 23, DOI: 10.5281/zenodo.20517
The importance of viticultural landscape features and ecosystem service enhancement for native butterflies in New Zealand vineyards
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