SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02e90034f9dad4bd5acf826eb628ce4b8b605bdfa27374e0c5b3397a32c7a3bf' 
  AND token = 'fcPJCMzxiDr/opJGSIUF/SnCqDsmBUCn6bmv5X+WRQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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