SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '429f5c8d509822b7001516d5c0d7a05346717280d55d5e6f434de54641815d71' 
  AND token = 'wrIkPZ5AVkAjwyP8Y4kskenheY2jPl9Cy4kdLq10nPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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