SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c22a445e714dcfcaa923c641682c7c9ca29d6a14255c16f37691f3282b2bb6af' 
  AND token = '/Zucy5nWhVVuXdscJtfJHUUYMj0UtzyrLY+o5UEmbdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}