SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab2c99cf94ed2c515db8e0c4dc37368208ac76091d200bf36bacca56520de890' 
  AND token = 'UXOFpdgjOymTVhNUa4zH9BU9MIOWbyxwGeLOA9RpMgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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