SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01bf4209f91a4bb2a366181d583583e1758b817a81f0c744843d4d22eeebabab' 
  AND token = '2YCpgtj6WqAQNc48Q2WP2SXYe8LOKhrg+0kLZcBSmUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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