- Sep 7, 2023
- 2 min read

Triop longicaudatus: The Long-Tailed Tadpole shrimp

Updated: Feb 15

Triop longicaudatus, commonly known as the Long-Tailed Tadpole shrimp, belongs to the familyTriopsidae. This species is known to inhabit a diverse range of habitats, including dry lake playas, ephemeral pools, and more, particularly during the warmer seasons of the year. While it is often associated with dry lake playas, Triop longicaudatus is not limited solely to these environments. It can frequently be observed in North America, especially in the southern United States, where it is quite prevalent.

The taxonomy of Triops is currently underdeveloped, confusing, and in need of revision. Presently, all Triops species in the US are referred to as Triop longicaudatus.

Anatomy: The characteristics outlined below may exhibit variations influenced by environmental conditions, population dynamics, and the organism's age.

Head:

Carapace:
- This shell-like structure overhangs the body and varies in shape and spines.

Naupliar & Compound eyes:
- They contain a pair of compound eyes with a naupliar eye on the anterior midline, and the distance between the eyes may vary.

Mandibular & Cervical groove:
- These features mark the division between the head and thorax.

Thorax:

Thoracopods:
- The thoracic appendages differ depending on the region of the body, specializing in specific functions such as sensory perception, locomotion, feeding, and respiration.

Reproductive Segments:
- Triops are generally hermaphroditic, but some populations may be gonochoric, with males and females being distinct.

Abdomen:

Segments are covered in spines.

Tail:

Cercopods:
- Long whiplike structures.

Morphology:

Size: Triop longicaudatus typically measures 2 to 3 inches in length, contingent on prevailing environmental conditions.
Coloration: The coloration varies among different populations.

Captivity and Growth:

Growth is influenced by multiple factors such as temperature, salinity, and care. These temperature ranges are based on our experience but do not represent the maximum or minimum.

Hatching Temperature Range: Triop longicaudatus hatches at temperatures ranging from 62 to 80°F.
Temperature Range for Adults: Adult Triop longicaudatus thrive within the temperature range of 62 to 80°F.

Hatching: At temperatures between 68 to 78°F, nauplii appear within 24 to 48 hours.

Growth Rate: Their growth rate is rapid to moderate, with sexual maturity achieved within 7 to 14 days. The average lifespan spans 8 to 10 weeks.

Behavior: Tadpole shrimps are generally benthic feeders, scavenging for food items or preying on other organisms. In the absence of readily available food, they may rise to the surface in search of sustenance. This behavior is also associated with low oxygen levels and the need to gather air.

Reproduction: Most populations are hermaphroditic, with females capable of producing eggs through parthenogenesis. However, some populations may be gonochoric, requiring both males and females for offspring production. Males court females during the mating process.

As Triop longicaudatus exhibits considerable variations, we categorize and track different lineages by assigning them specific IDs, denoted as (Location - Type). For more information on each lineage, please click on the corresponding link: