Retention of larval characters even after sexual maturity is called

Options

A. parthenogenesis
B. ontogenesis
C. phyllogenesis
D. neoteny

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that describes the retention of larval characteristics even after an organism reaches sexual maturity.

2. **Identifying the Concept**: The phenomenon where an organism retains juvenile or larval traits throughout its adult life is a specific biological process.

3. **Recalling Relevant Terminology**: The term that describes this process is "neoteny." Neoteny refers to the retention of juvenile features in the adult stage of an organism.

4. **Contextualizing Neoteny**: Neoteny is commonly observed in certain amphibians, particularly within the class Urodela (which includes salamanders and newts). In these organisms, they may retain gills and other larval characteristics even as adults.

5. **Conclusion**: Therefore, the answer to the question is "neoteny."

### Final Answer:
The retention of larval characters even after sexual maturity is called **neoteny**.

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