Sorensenella prehensor is a species in the endemic New Zealand genus Sorensenella described by Reginald Pocock in 1903.[1] Ray Forster revised the genus Sorensenella in 1954.[2] As well as the nominate subspecies, Sorensenella prehensor prehensor, added two other subspecies, S. prehensor nitida and S. prehensor obesa. This species is found from Auckland to North Cape in New Zealand's North Island.
| Sorensenella prehensor | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Chelicerata |
| Class: | Arachnida |
| Order: | Opiliones |
| Family: | Triaenonychidae |
| Genus: | Sorensenella |
| Species: | S. prehensor
|
| Binomial name | |
| Sorensenella prehensor | |
Taxonomy
edit
| Sorensenella prehensor | |
|---|---|
| |
| Sorensenella prehensor nitida holotype specimen from the Kopuapounamu River, Ruakumara Range, East Cape, New Zealand | |
| Scientific classification
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Chelicerata |
| Class: | Arachnida |
| Order: | Opiliones |
| Family: | Triaenonychidae |
| Genus: | Sorensenella |
| Species: | |
| Subspecies: | S. p. nitida
|
| Trinomial name | |
| Sorensenella prehensor nitida Forster, 1954[2]
| |
Sorensenella prehensor is the type species of the genus Sorensenella and was described by Pocock in 1903.[1] Pocock did not explicitly designate a type specimen.[1] However, Forster's 1954 revision of the genus Sorensenella noted there was only a single specimen in the British Museum, and that Pocock's description also implied this.[2] Forster also noted that Carl F. Roewer's figure[3] of S. prehensor was a specimen of S. bicornis.[2]
Forster's revision in his 1954 monograph added two subspecies based on minor morphological and geographical grounds: S. prehensor nitida and S. prehensor obesa.[2] Sorensenella prehensor nitida is a member of the New Zealand endemic genus Sorensenella in the opilionid (harvestman) family Triaenonychidae. S. prehensor nitida was differented on the basis of geographic range and eyemound characteristics.[2]
Description
editSorensenella prehensor has the general characteristics of Sorensenella. Forster's redescription based on a greater range of material than was available to Pocock notes the following additional characters. Colour reddish brown with a black pattern on the scute (the unsegmented portion of the carapace). Free tergites are blackish with a transverse row of pale brown spots. The chelicerae and pedipalps have reticulated dorsal markings. Females have more slender pedipalps than males. The tubercles (pointed protuberances) behind the anterior corners of the carapace are also smaller, as is the tubercle on top of the eyemound.[2]
The nominate subspecies S. prehensor prehensor may be distinguished from S. prehensor nitida by having a larger tubercle on the eyemound in both males and females. Sorensenella prehensor nitida is also confined to East Cape, while S. p. prehensor is found in the northern North Island. Males of this subspecies have larger pedipalps than females. While Forster provided measurements for both males and females, he did not give any additional descriptive detail other than noting there is a pair of subequal tubercles behind each anterior corner of the carapace and the inner tubercle is strong. The only figures provided depict the male and female eyemounds.[2]
Sorensenella p. prehensor may be separated from S. p. obesa by the latter's greater size and slightly backward-pointing eyemound tubercle. Both are found at North Cape, with S. p. obesa confined to a separate population in the northernmost part of the region.[2]
Distribution
editSorensenella prehensor is found in the northern North Island of New Zealand, from Auckland to North Cape.[2]
Conservation status
editThis species has not been assessed as part of the New Zealand Threat Classification system.[6]
References
edit- ^ a b c d Pocock, Reginald Innes (1903-01-01). "On some new harvest-spiders of the order Opiliones from the southern continents". Proceedings of the Zoological Society of London. 1902: 392–413.
- ^ a b c d e f g h i j Forster, Raymond Robert (1954-07-01). "The New Zealand harvestmen (sub-order Laniatores)". Canterbury Museum bulletin. 2: 1–329.
- ^ Roewer, Carl Friedrich (1931-01-01). "Über Triaenonychiden (6. Ergänzung der "Weberknechte der Erde", 1923)". Zeitschrift für wissenschaftliche Zoologie. 138: 137–185.
- ^ "Te Papa Collections online: Sorensenella prehensor nitida". Retrieved 31 May 2024.
- ^ Palma, Ricardo L.; Lovis, Pamela; Tither, Christina (1989-09-01). "An annotated list of primary types of the phyla Arthropoda (except Crustacea) and Tardigrada held in the National Museum of New Zealand". National Museum of New Zealand Miscellaneous Series. 20: 1–49.
- ^ Buckley, T. R.; Palma, R. L.; Johns, P. M.; Gleeson, D. M.; Heath, A. C. G.; Hitchmough, Rod; Stringer, I. A. N. (2012-06-21). "The conservation status of small or less well known groups of New Zealand terrestrial invertebrates". New Zealand Entomologist. 35 (2): 137–143. doi:10.1080/00779962.2012.686319.