SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1965aaf8ae7160755e6f2b5be321a3fc492a08e161d83f372803a083b98a28b' 
  AND token = 'P6aOEX+TLKMxS8me/+BgpXLqnA53ANKZ0rSb7ojjDu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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