Questions tagged [invertebrates]

A paraphyletic classification for animals lacking a vertebral column.

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34
votes
2answers
100k views

How long can an octopus survive out of the water?

I saw videos of octopuses crawling on the ground and I was wondering how long an octopus can survive when out of the water? Does it depend on either its size (i.e., does a big octopus from deep sea ...
20
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1answer
966 views

What are these bladder snail parasites?

I collected some bladder snails several months ago. While checking them out one day, I noticed that they were now infested with worm-like ectoparasites. Appearance and behavior Here's a picture of a ...
20
votes
2answers
403 views

Selection for less efficient egg transfer in Human Botfly life cycle

I have heard that the Human Botfly transfers its eggs through other invertebrates, and it strikes my curiosity that if an insect could simply land on its host directly to deposit its eggs, then why ...
15
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1answer
4k views

Why do crabs spit?

Last year I photographed this juvenile Sally Lightfoot Crab (Grapsus grapsus) 'spitting' (click for larger view): I thought I'd look up more information on this behavior, but couldn't find any ...
14
votes
2answers
2k views

Can you identify this fossil?

I found this fossil near a beach in Victoria, Australia. Can anyone identify it? It is roughly the size of an Australian 20 cent piece (~30 mm). I think it might have been washed down from an eroding ...
14
votes
1answer
754 views

Identification of colorful jelly-like marine creature

I'm on my trip to Gulangyu Island, Xiamen, Fujian Province, China. Today(4th February 2017), at 12:13 A.M., I saw a beach filled with huge rocks on which various dry shells reside. Among the shells, I ...
9
votes
2answers
4k views

Spider identification

This red spider has set up a web in my yard, in South Eastern, Texas, United States: The spider itself is about an inch long (2.5 cm), and is predominantly red to brown in color, with red legs, and a ...
9
votes
3answers
1k views

Are there echolocating insects?

Echolocation is the ability to obtain spatial information of the surroundings from echos generated by the animal. There are bats and other vertebrates that naturally use it. I was wondering if this ...
8
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1answer
4k views

What biological constraints are there on how large a spider can grow?

Spiders fascinate me, but what intrigues me the most is just how big some spiders can get, which leads me to my question. What biological constraints (if any) would limit how large a spider could grow,...
8
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1answer
652 views

ID a shell from Puerto Rico

I recently found this in Rincon Puerto Rico on the beach. I assumed it was a baby sea turtle shell or some kind of turtle. Someone that frequents Puerto Rico said it was not. Does anybody know what ...
8
votes
1answer
133 views

strange creature

We live on the Gulf Coast in Corpus Christi, Texas. There was a big thunderstorm that dumped several inches of rain at our home. We live about a quarter of a mile from the bay. My daughter found it ...
8
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1answer
2k views

Aquarium snail identification

Many of these little snails suddenly appeared in our aquarium from nowhere. I suspect that some snail eggs hitched a ride with some recently purchased plants. Can anyone identify the species? I am ...
8
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1answer
160 views

Is the number of legs in myriapoda determined entirely by the genome?

Myriapoda (comprising, among others, millipedes and centipedes) can have hundreds of legs (Illacme plenipes having up to 750 legs). Interestingly, the number of legs (or leg pairs) appears to differ ...
7
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2answers
13k views

Do octopuses have better eyes than humans?

I've read that unlike humans, octopuses have eyes "designed" the "right way", i.e. with the nerve fibers behind the retina, thus getting rid of the blind spot we humans have as well as theoretically ...
7
votes
1answer
92 views

Which poison makes seastars inedible to possible predators?

In the new citizen science project (see: Sea Floor Explorer), numbers of seastars, scallops, crustaceans and other animals are counted. Already one can see a heavy bias in favor of seastars, both the ...
7
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0answers
198 views

What is this underwater creature?

West Bali, about 10 meters deep. Body is roughly 10 cm across. Does not move.
6
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1answer
379 views

What is this strange horned, slug-like coral reef dwelling creature?

On the first episode of BBC's Blue Planet II they visited a coral reef and showed some odd reef-dwelling creatures as part of their establishing shots, but they did not identify the creatures. What ...
6
votes
1answer
156 views

What is this long, thin and segmented insect I found in my house in India?

Found this inside my house, along the wall, there were few going somewhere few distance from each other. I suspect it is a centipede but didn't found similar images on Google. What is this? Location:...
6
votes
1answer
269 views

Are there any theories why such an imbalance in chirality of molluscs?

Most gastropods exhibit sinistral (right hand) winding of their shells. But very few species are anti sinistral. Have there been any theories as to why such a great difference?
5
votes
1answer
604 views

What are these tiny creatures swimming around my aquarium?

I was checking out my aquarium today, and decided to scoop out a water sample and take a look at it more closely. What I discovered were numerous, very, very tiny white worms (?) swimming around in ...
5
votes
2answers
160 views

Why do Centipedes always have an odd number of pairs of legs?

Furthermore, centipedes are within the Myriapoda, a subphylum of arthropods which also contains millipedes. Do millipedes also have an odd number pair of legs?
5
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1answer
97 views

Anyone know what this it?

More than 1 washed up on a beach in Ireland..close to some big jellyfish
5
votes
1answer
1k views

Species identification - what kind of worm is this?

I am finding these worms in my bathroom since summer arrived. I have been finding these on floor, walls and damp towel I left hung overnight in bathroom couple of times. When these worms are squished, ...
4
votes
2answers
118 views

What is this agglomeration of pink cells I found attached to a stone?

Photo taken in a garden in Singapore. The organism is attached to a stone, close to water. Many of these were there. Size approx 3cm. The shell of this eggs is very soft. When touched, a pink ...
4
votes
1answer
423 views

What is the largest species of polychaete?

My Google searches seemed to avail no results. My question is: What is the largest living species in the class Polychaeta? That's about it. I understand that there will be few accessible weights for ...
4
votes
1answer
248 views

Species identification - greenish blue ocean worm (nudibranch?) in Perhentian Islands, Malaysia

We found this on a beach at the Perhentian Islands, Malaysia in March, 2016 and cannot identify it. It's some sort of worm-type creature with many legs and bluish back about 15cm long. The legs ...
4
votes
1answer
188 views

What kind of hot pink eggs are these? [duplicate]

I saw a dozen or more clusters of what I think are insect eggs attached to a few vertical sticks protruding from a small pond, and a few more to stalks of grass nearby. Location is in Hsinchu County, ...
4
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2answers
1k views

Did radial symmetry evolve twice?

In the history of animal evolution, both the Cnidarians and the Echinoderms have radial symmetry, according to this cladogram: Source: http://www.cpalms.org/Public/PreviewResourceLesson/Preview/45851 ...
4
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0answers
216 views

Do invertebrates dream? [closed]

From Wikipedia: Studies have observed dreaming in mammals such as monkeys, dogs, cats, rats, elephants and shrews. There have also been signs of dreaming in birds and reptiles. Have there been ...
3
votes
1answer
137 views

Identification of a small flat bug

So for the last few days I have been noticing these small bugs in my bathroom -- they don't appear frequently, and I see them once or twice a month. The characteristics and behavior I observed are as ...
3
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1answer
410 views

Sex determination in cephalopod?

I see some source say octopus do not have sex chromosome. So what's the sex determination mechanism for cephalopods?
3
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2answers
794 views

ID for red millipede swarm near my place

Location:Hyderabad,South India. These worms usually come out when it rains,these worms are the most common ones any help in figuring out them,they come in groups too.
3
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1answer
186 views

Which kind of caterpillar is this?

Which caterpillar is this? It was found in mid Europe during this time (April). Size about 2cm in length.
3
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0answers
52 views

Strange planarian/leech like creatures found with California blackworms

I've been trying to ID these things myself but to no avail. They came with a shipment of California blackworms from Florida. I've heard so many ID's and apparently it's not uncommon to get these ...
3
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0answers
52 views

How do insects recognize their host plants?

Many insects, like butterflies have specific host plants on which they feed or lay eggs. While researching about some butterflies, I found that they lay their eggs on certain specific plants and their ...
3
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0answers
72 views

Are baby centipedes poisonous like the adults?

I know that centipedes have an appendage called "poison claw".But I am not sure if the same is there in the baby centipedes and if its functional like that of the adults. So are baby centipedes ...
2
votes
1answer
91 views

Species identification. Is this a leech?

The pictured creature, shown at the bottom of a glass, was attached to a friend’s child after he was swimming in the Ottawa River today. It stretches out to roughly an inch in length but in this “...
2
votes
1answer
285 views

What is the reason behind the subphylum name “Urochordata” for tunicates?

There are two major invertebrate subphyla of the chordates (phylum Chordata): Cephalochordata (the lancelets) Urochordata, aka Tunicata (the tunicates) My understanding is that the cephalochordates ...
2
votes
1answer
144 views

How do you determine the length of an annelid?

I'm currently studying a horse-leech, and would like to know if it is fully grown or not. When I read about different annelid species a maximum length is often given, so I wonder if there is some ...
2
votes
1answer
139 views

will an earthworm survive after covering its skin with a wet cloth

I am very curious about this question. I got this doubt when I was studying anatomy and physiology of the earthworm Lampito mauritii. It breathes through its skin (cutaneous respiration) and if we ...
2
votes
1answer
68 views

Identify arthropod with many legs in Mumbai

Can someone please identify this ~5 cm long arthropod? I've been finding one of these every 2-3 days inside my apartment ever since rainy season started here in Mumbai (June). The bulb portion is its ...
2
votes
2answers
89 views

Bug Identification: Tiny Bugs in Fairport NY

We have been finding a ton of these tiny bugs (pin head size or smaller) outside on our patios, outdoor tables, on the grill, etc. What are they and how do we get rid of them?
2
votes
1answer
130 views

Help with jellyfish species identification

Our research group (Evolutionary Genetics Group, University of Zurich) has received a letter from a special needs child who has kindly asked us to identify three jellyfish species. Unfortunately, the ...
2
votes
1answer
696 views

Do hornets remember and recognize a human? Do they have any (kind of) memory?

hornetology So it happens that a hornet (vespa crabro) flew inside my house today and now is being held in a plastic container (I made some holes to let it breathe). But it also happens not just this ...
2
votes
1answer
203 views

What is this discarded exoskeleton from?

This morning I was looking round the garden and found this sticking out of a pit in patch of soil, next to the wall of the house (in a trough sort of thing). I came to the conclusion it must be part ...
2
votes
1answer
40 views

Which is the guideline to choose a molecular target to identify vertebrate hosts from arthropod bloodmeals?

There are some molecular targets to identify vertebrate hosts from arthropod bloodmeals including the Cyt b gene and the COI gene. Which are the standards or characteristics that I have to bear in ...
2
votes
1answer
226 views

Help in identifying an unknown Golden Worm/Larvae

Can anyone help me to recognize this type of species? Is it a clustered worms or clustered larvae? Location is in Bali, Indonesia. Recently this species is goes viral, but people here always link this ...
1
vote
1answer
144 views

Unknown mite species in plant pots

Does anybody know what kind of mite this is? It is living in my pepper plants' pots. My region is south of Germany. (Baden-Württemberg) I will try to take another picture including some size ...
1
vote
2answers
348 views

Cockroach brain functional anatomy

In insects like the cockroach the brain is distributed, i.e. some parts lie in the head and some in the abdominal cavity. Which part is responsible for controlling locomotion?
1
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1answer
56 views

Im trying to find out what type of snail this is

The snail is pretty large and located in texas.