Acanthomenexenus polyacanthus
| Acanthomenexenus polyacanthus | ||||||||||||
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Pair of Acanthomenexenus polyacanthus |
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| Scientific name | ||||||||||||
| Acanthomenexenus polyacanthus | ||||||||||||
| ( Dohrn , 1910) |
Acanthomenexenus polyacanthus is sometimes as frequent thorn cricket described insect species from the order of the stick insects (Phasmatodea) located on Sangihe Besar one of the Sangihe Islands north of Sulawesi is home.
features
The species is wingless in both sexes. In addition to the elongated habitus typical of stick insects , the variable coloration and the many thin and especially in the slender males very long spines in relation to the body are particularly striking. The females reach a length of 55 to 60 millimeters. Their spines are arranged in pairs on the head, the thorax and almost over the entire abdomen , forming a double row. They are longest on the meso- and metathorax and are supplemented by spines that are further on the edge. The base of the longest pair of spines on the meso- and metathorax is bright orange-red in color. Like the other spines, their tip is very dark in color. In addition to animals that are almost uniformly orange-brown, there are also those with more contrasting drawings. This is created by a light, often orange-brown, broad band on the body, which is flanked by a darker color. It begins on the forehead, often divides the eyes into a light, upper and a dark lower area and then runs sharply defined over the thorax and almost the entire abdomen. To the side of this band, the color of the body, as well as that of the legs and the antennae, which reach about 2/3 body length, vary from light brown to dark brown. Especially females with a dark brown base color often show black dividing lines between the light band on the head and the meso- and metathorax.
Males will only be around 40 to 45 millimeters long. They are similarly prickly, with the last spines already on the anterior abdominal segments. So far, two color forms are known, both of which occur in the offspring independently of the parent animals. One is completely dark brown in color, while the other has a dark blue, almost metallic shimmering color. The males are completely drawn in the respective color. Only shortly after molting to the imago are the later shiny black-brown eyes still yellow and the abdomen of the blue male is still red-brown.
Reproduction
The females simply drop the bizarre-looking, very small eggs to the ground. After only 10 to 16 weeks, the only five millimeters long, initially completely green nymphs hatch from these . In the second stage of development they are light brown to straw-colored. During the three to four month period of growth, they take on more and more of the coloration of the adults . The males can also show a light, but usually narrower stripe on their backs. Females are usually adult about two weeks later than males of the same age.
Systematics
Heinrich Dohrn described the species in 1910 using a female as Menexenus polyacanthus . This female was deposited as a holotype and is in the Museum and Institute of Zoology in Warsaw . Later, Menexenus polyacanthus was regarded as a synonym and temporarily also as a subspecies of Menexenus horridus (today Acanthomenexenus horridus ). Only after living animals were discovered again, including the first males, was the species recognized as such again in 2008/2009. At the same time it was transferred to the newly established genus Acanthomenexenus , as well as some other species previously belonging to the genus Menexenus .
Terrarium keeping
Acanthomenexenus polyacanthus is a stick insect that is easy to care for in the terrarium . It is easy to keep and grow at room temperature. The humidity can rise to values between 70 and 80 percent. Rose plants such as blackberries and hawthorns, but also buddleia , hazel and oak are eaten . The nymphs in particular also like to accept ferns . The forage plants are placed in the terrarium as leafy twigs in narrow-necked vases and should be sprayed with water from time to time. The eggs can be left in the terrarium if a slightly moist substrate covers the ground.
The species is listed by the Phasmid Study Group under PSG number 295. The breeding lines go back to animals found on the Sangihe Island Sangihe Besar in 2007 and 2008 respectively. The latter were collected on Mount Sahendaruman.
photos
L1 nymph
subadult male
blue and brown male
differently colored females
Individual evidence
- ^ A b Paul D. Brock : Phasmida Species File Online . Version 2.1 / 4.0. (accessed on December 27, 2010)
- ↑ a b c Alexander Esch: stick insects, ghosts, walking leaves: successful keeping of phasmids . Natur und Tier-Verlag, Münster 2012, p. 45, ISBN 3866592213
- ↑ a b c stabschrecken.com: Posture reports -Streeches, ghosts, walking leaves , iter novellum Verlag, Saarbrücken 2010, p. 45, ISBN 978-3-00-031913-6
- ↑ a b Phasmid page ( Memento of the original from May 2, 2011 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. by Frank H. Hennemann & Oskar V. Conle
- ^ Heinrich Dohrn : Stettiner Entomologische Zeitschrift , Volume 71, year 1910, p. 406. 1910, online version
- ↑ P. Brock, F. Hennemann & B. Morgan: Bulletin d'Arthropoda , 2008/2009, (36), 9
- ↑ Phasmid Study Group Culture List ( Memento from December 5, 2012 in the web archive archive.today ) (English)
