SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c8103e662e37da4f150257457a12035d4fc1fb80ea8efb7fd587999c5ea19675' 
  AND token = 'X1VW/hD9ZfL/23tP8CYhHxIsXwuW/t4xrZFawtAxRIg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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