SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13f6aeaa86f6823bc449346e555f625f4dcdaec2ead69e70a2c8df7577d43970' 
  AND token = '9WV9hV5LbRKDXEj/FGjGBXVmMG2vbUQVDkROsevA7bU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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