Dewdrop Spider: All You Need to Know in a Quick Guide

Dewdrop spiders, belonging to the Argyrodes genus, are fascinating creatures known for their unique appearance and behavior. These small spiders belong to the Theridiidae family and can be found in various locations across the world. They are named after the silvery, dew-like droplets that cover their body, giving them a distinctive, shiny look.

These spiders exhibit intriguing behaviors, such as kleptoparasitism, where they steal prey from the webs of other spiders. This clever tactic allows them to survive in different environments without needing to create their own webs. Additionally, dewdrop spiders have a diverse range of appearances and colors, making them a fascinating subject for arachnid enthusiasts.

Dewdrop Spider Basics

Species and Family

Dewdrop spiders belong to the family Theridiidae and are part of the genus Argyrodes. They are tiny spiders found in various parts of the world, particularly in the Americas and Asia.

Appearance

Dewdrop spiders get their name from their unique appearance, which closely resembles a shiny drop of dew. They are small and have a silvery or translucent body. Features of the dewdrop spider include:

  • Tiny size
  • Silvery or translucent body
  • Resemble a drop of dew

To better understand the appearance of dewdrop spiders, let’s compare them with another spider species, the brown recluse spider.

Feature Dewdrop Spider Brown Recluse Spider
Size Tiny Medium (about 1 inch)
Body Shape Oval, drop-like Oval with distinct markings
Color Silvery or translucent Brown with dark violin mark

As you can see, despite being both spiders, dewdrop spiders and brown recluse spiders have distinct differences in their appearance, making it easy to differentiate between them. Overall, the dewdrop spider is a fascinating creature with a unique appearance, contributing to the diverse world of nature and our incredible spider species.

Habitat and Distribution

The Dewdrop Spider is known for its habitat across various locations. In Washington state, these spiders can be found in eastern regions and the Seattle area1. Their distribution may also include gardens and around homes, as evident in the case of the Jumping Spider2.

  • Habitat: Gardens, homes, and various environments
  • Location: Eastern Washington, Seattle area

These spiders adapt well to different environments. For instance, the Yellow Sac Spider is known for being quite versatile:

  • Size: Body about a quarter to a half-inch long
  • Color: Yellow, white, or greenish, with darker legs and upper body1

It’s important to recognize and appreciate the diversity and adaptability of the Dewdrop Spiders in their habitat and distribution.

Kleptoparasitic Lifestyle

Evidence of Parasitic Behavior

Dewdrop spiders (genus Argyrodes) are known for their kleptoparasitic lifestyle. This means that they steal food from other spiders, rather than capturing prey themselves. A key example is the Argyrodes antipodianus species, which relies on other spiders’ webs to acquire food. These spiders have been observed living and foraging in the webs of their host spiders, allowing them to survive without spinning elaborate webs of their own1.

  • Features of kleptoparasitic lifestyle:
    • Steal food from host spiders
    • Live within host spider webs
    • Rely on vibratory cues from host spiders during prey capture

Host Spider Interaction

Dewdrop spiders often target larger orb-weaver species, such as silver argiope spiders2. They position themselves at the outer edge of the host web, where they wait and observe the host’s activities. When the host spider captures prey, dewdrop spiders detect the vibrations and move towards the center of the web, where they either feed alongside the host or steal small pieces of prey1.

Host spider interactions also extend to egg sacs, where kleptoparasitic behaviors have been reported. Dewdrop spiders remain close to the host spider’s egg sac, and there are cases wherein they feed on host’s eggs3. Host spiders may exhibit defensive behaviors, but dewdrop spiders mostly manage to coexist within the host webs without causing significant harm.

  • Characteristics of host spider interaction:
    • Target larger orb-weaver species
    • Position themselves at the web’s outer edge
    • Move towards the center during prey capture

Comparison Table: Dewdrop Spiders vs. Host Spiders

Dewdrop Spiders (Kleptoparasites) Host Spiders
Food Acquisition Steal from host spider Capture own prey
Web Use Lives within host’s web Creates own web
Prey Interaction Relies on host’s activities Independently active

Unique Physical Features

Male and Female Characteristics

Dewdrop spiders, belonging to the family Theridiidae, exhibit several distinct features between males and females.

  • Males have smaller bodies but longer legs compared to females
  • Females often have more vibrant colors on their abdomens

For example, male spiders might have less pronounced markings, while female spiders can display more striking patterns, which can be observed in photos of these arachnids.

Body Length

The body length of dewdrop spiders varies between the two sexes:

  • Male dewdrop spiders: 1.5 to 3 mm
  • Female dewdrop spiders: 3 to 5 mm

These measurements indicate that female dewdrop spiders are generally larger in size than their male counterparts.

Abdomens

Abdomens of dewdrop spiders also show differences between males and females:

  • Male abdomens tend to be elongated and narrower
  • Female abdomens are often rounder and more bulbous

A comparison of features in bullet points:

  • Males: smaller body, longer legs, less vibrant colors, elongated and narrower abdomen
  • Females: larger body, shorter legs, vibrant colors, rounder and bulbous abdomen

It’s essential to note that while these differences are typical in dewdrop spiders, variations may exist within the species as well.

Behavior and Adaptations

Predation and Protection

The Dewdrop Spider (Argyrodes antipodianus) is a unique spider species, often observed in nature with its distinctive behavior. This tiny insect takes advantage of its environment by living in the webs of larger spiders, relying on them for protection and stealing their food. Some key features of the Dewdrop Spider include:

  • Size: Small, typically less than 3mm
  • Coloration: Shiny, reflective body, resembling a dewdrop
  • Habitat: Found in webs of larger host spiders

The Dewdrop Spider’s reflective body helps it blend in with the dewdrops on the web, making it less likely to be detected by its host, birds, and other predators. Additionally, since the spider is active during the day, it benefits from the protection of the sun that reduces the likelihood of bird predation.

Reproduction

Ron Atkinson, a renowned spider expert, identified the Dewdrop Spider’s interesting reproductive behavior. To reproduce, the female Dewdrop Spider releases a pheromone that attracts males of other spider species. Once lured into the web, the male becomes immobilized and serves as a food source for the female and her offspring.

Here is a comparison table highlighting certain characteristics between Dewdrop Spiders and other spider species:

Feature Dewdrop Spider Other Spider Species
Size Small (<3mm) Varies
Habitat Host spider’s web Various locations
Coloration Reflective Varies
Reproductive Method Pheromone luring Different strategies
Feeding Stealing host’s food Hunting or trapping

In summary, the Dewdrop Spider displays remarkable adaptations and behavior that allow it to survive in the complex world of insects. By living in the webs of larger spiders, it enjoys protection from predators as well as easy access to food, while its unique reproductive method ensures the survival of the species.

Footnotes

  1. Washington State Department of Health 2 3 4

  2. Washington State University Department of Entomology 2

  3. Dual pathways in social evolution: Population genetic of spider behaviors

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Dewdrop Spider

 

Subject:  Tiny spider found near farm
Geographic location of the bug:  Blacksburg, VA
Date: 10/10/2017
Time: 11:01 AM EDT
Hi,
I found this spider near a farm. Caught it in a jar and it laid its eggs, and now looks a lot more deflated. What species could she be? Thanks.
How you want your letter signed:  Daniel

Dewdrop Spider

Dear Daniel,
This is a kleptoparasitic Dewdrop Spider, probably
Argyrodes pluto, which according to BugGuide has a range of “USA – From Maryland, Virginia, Missouri, southwest to Chihuahua and Jamaica.”  Kleptoparasites steal food from other species.  According to BugGuide:  “Argyrodes spiders (and related genera) are kleptoparasitic. They live in the outer edges of other spiders’ webs and move in to steal prey when the coast is clear. Apparently the method of at least one species (Argyrodes nephilae) is to attach a line of silk then cut the wrapped prey out of the host web. The bundle swings free and can be taken to the outskirts of the main web to be eaten in relative safety.”

Letter 2 – Possibly Dewdrop Spider

 

Subject: Dewdrop Spider
Location: Laurens County, SC, USA
October 29, 2012 10:39 am
I found this tiny spider on the web of an orbweaver. I’m pretty sure it is one of the dewdrops, but cannot make further ID.
Signature: Gene Ott

Possibly Dewdrop Spider

Hi Gene,
This does resemble the Dewdrop Spiders from the genus
Argyrodes posted to BugGuide in shape, but in coloration, it is different.  There is also a resemblance to another kleptoparasite genus of Cobweb Spiders posted on BugGuide, Neospintharus, formerly classified as Argyrodes.  Kleptoparasites are organisms that steal food from other creatures.  A Dewdrop Spider, according to BugGuide, “steals small insects from the orb webs of other spiders, as well as pillages large prey items that have already been caught and often predigested by the host spider.”   We will post it with a tentative identification and see if any of our readers can provide additional information.  Thanks for sending this interesting submission.

Daniel,
Thank you very much.  I will check the site to see what occurs.
Gene

Authors

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  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

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  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

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