SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '333456932c26dc227e5b3e7909422c360c8bad7fd427899e1cf74c7865ee6ec0' 
  AND token = 'l3jL1aLMlCj5uECmSugrQdbI9X+rUB9FsQIsq7rwGLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}