#dusky cockroach

Dusky Cockroach - Ectobius lapponicus (nymph)

With a species of Termite finally receiving a proper introduction on this blog and further expanding the scope of the insects found here, it seems best to also give a small reminder of the other individuals within that particular insect order. Moreover, with some fresh images, it offers the chance to contrast and compare the recently added Pacific Dampwood Termite with its distant relatives: the Cockroaches of Blattodea. Furthermore, today's images highlight something new from the realm of Dusky Cockroaches: nymphs, hard as that may be to believe. Despite their small size, these are exceptionally swift runners, but they are not as fast as the adults. As well, being insect nymphs, these individuals rely on running capabilities to evade danger and keep to shaded spots until receiving functional wings upon completion of their final molt. Cross-referencing with other pictures of this species' nymphs, it appears that the sexually dimorphic traits manifest relatively early in their development. As such, it might be possible to determine whether you have found a female or male Roach nymph at a cursory glance, and we appear to have female nymphs here. While female Dusky Roaches tend to keep to this shape and have upturned cerci, the male Roaches don't sport amber coloration in adulthood, and they are more streamlined with short outward cerci. Of course, I could be completely off-base with these nymphs here.

In any case, we can be sure that the specimens found here are nymphs, as the dorsal side of their abdomens are completely exposed due to lack of wings. As mentioned above, this insect will gain wings which cover its abdomen upon completion of an adulthood molt. In the case of Dusky Cockroaches, they are very much capable of flight, and I have seen many instances of this flight during investigations of them within my neighborhood's undergrowth. Interestingly, I've typically witnessed flight during the daylight hours, and when flight had occurred, the landing was usually in a darker area. At nighttime, including when these pictures were taken, mobility is achieved through swift scampering, and even so young, nymphs like this are quick on their tarsal claws. Just to further clarify, however, Roaches as a whole are well-adapted to low light or low visibility conditions, and they thusly benefit from strong night vision for navigation. They are not necessarily adverse to light, but light can stimulate them to move, and in this particular case, the mobile activity from these nymphs was likely due to the camera flash. It seems drastic, but insects must rely on their sensory arrays to keep out of danger. This not only includes visual acuity, but also antennae flicking, and the many leg spines and rear cerci along the body. These features are most definitely visible here, even during the nymph stages.

@sketch-wolf submitted: I’d like some help with this one since no site on norwegian bugs had anything like it (so it might be a nymph??). apologies for the poor pic, it was too tiny and shiny for me to get a better one. but some additional details i could see with my eyes was it appeared to have at least one set of translucent wings folded over it’s dark brown body, said body had many segments, and it ended in two tiny tails. Location is south-east norway.

Dusky Cockroach - Ectobius lapponicus

While not as glamorous as the Eastern Black Swallowtail Butterfly, these scampering insects showcase the differences between males and females of this specie. The Dusky Cockroach has been examined on this blog before, with 2 individuals found during 2 separate visits to Kleinburg. For this post however, the multitude of insects found on the metal railing of the bridge and among the foliage where found locally in my neighborhood. The bridge itself was nestled over a stream in a wooded area so a lot of these insects running around made sense. Distinguishing between male and female Dusky Cockroaches is very straightforward as they are differently morphologically: males are longer and thinner with darker coloration on the thorax while females are wider, more compact and a more orange-brown color. Both possess wings, but during the photography, the males were more eager to use their wings but would never fly far away, just further down the bridge. Perhaps they were all searching for mates on this bridge?

While Roaches have a negative reputation for the germs and grime they can bring into a house, there’s little reason to panic over this specie. Ectobius Roaches prefer the forests and the soil over an urban environment. Crawling around the woods, they are quite handy as detritivores and decomposers. It was a surprise to find one in the garden (Pictures 1, 7 and 9). It chose to remain in the shadows beneath the leaves, only emerging to sprint away when my shadow covered more ground and it dropped onto the soil. While not of much concern as mentioned earlier, I’ll be checking that area come summer thoroughly to see if this specie decides to make this yard its home. A new specie introduced to an ecosystem may cause changes and observance will determine if the changes are beneficiary, neutral or negative. These Roaches are no stranger to being observed as the Ectobius Roaches found in North America were all introduced from Eurasia. Their activity seems neutral over here, so that’s a relief.

Dusky Cockroach - Ectobius lapponicus

In a proliferating ecosystem, there needs to be ample detritivores to help cleanse the ground and remove decaying matter so that new life can flourish. Some of us may look down on them, especially since a few of these detritivores prefer the urban lifestyle and bring some bad habits with them, but overall these hardy insects are essential and do tremendous good. If you’re skittish about them, at least they prefer to hide in the darkness and keep out of sight. If disturbed, they can sprint quickly regardless of surface! For my observations, they can go over, under and scale plants thoughtfully despite their quick speed. And if there’s nowhere to run, the males can fly reasonably well to escape, and I speculate that females do the same (I have not seen a female Dusky Roach in flight). The former may have longer wings than the latter, but even the best flying Roaches prefer to run away from danger and the conceal their flattened bodies in any crevice or alcove of soil they can squeeze into. On the subject of males and females, while a majority of this post focuses on several male individuals crawling among the greenery, the first 2 images are a more important find. If there was any doubt that the two were distinct species, the finding of a mating pair should clarify that the slimmer, darker male and the rounder, amber female are both E. lapponicus. 

Remember that in the insect world it’s not unusually for there to be profound differences between male and female specimens. The differences could be so much so that to the uninitiated they appear to be 2 entirely difference species. One of my favorite examples to demonstrate this phenomenon are the winged False Honey Ant alates. One large, one small, and yet they still fit in the same colony! Leaders of Termite colonies (close relatives of Roaches) also have differences between them that could lead to the same idea, and yet they are likely to be the same specie. Unlike the more matriarchal Hymenopteran system, Blattodean colonies feature a Queen Termite and a King Termite,  and if you’re curious, I do recommend you search up both to see the differences for yourself. Besides specimen differences, the reason I mention all of this is that while Roaches don’t form colonies the way Termites would, they can form highly social aggregations that are a few steps away from eusocial. Dusky Roaches strike me more as the type to form aggregations and cooperate when need be, while other species are more gregarious and make collective decisions on where to travel to and/or find food. That behavior sounds very familiar...a certain type of beloved fuzzy, flying insect that cooperate for a common goal. 

Skovkakerlak (Ectobius lapponicus)

Dusky Cockroach - Ectobius lapponicus

Also known as the Tawny Cockroach, this specie of Roach is native to Europe, and yet somehow found its way over to North America. While in general, roaches are depicted as dirty creatures, but these Roaches in the wild are quite harmless. Pictured here, in the wilds of Kleinburg, we have male and female roaches: the 1st picture is of a male and the other 2 pictures are of females. The clearest distinction between the 2 is that the male has longer wings which cover their abdomen, while females have shorter wings. As while, the head and thorax colors are distinct from each other as well. But no matter what they look like, they both have flattened bodies and hardened exoskeletons! Something else to note, the 3rd picture seems to depict a more developed female as evidenced by the large pronotum (which now appears to cover the head, a characteristic of most roaches) and the hind legs having enlarged spines (also a characteristic of roaches). Whatever they look like, they love to scamper about and hide.