SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f71f1cddb9ed0e8d236852d1e16c307306e8a414472bbbec9cee2fd48bcfd81' 
  AND token = 'cQ+mRqtplfQ01UU4rEoL4OTmyTBjSgZ1izFhAwoJE4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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