SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a11c305a6dc770923f2e21f5bc094def21f7bc861e591c6159625854d6ee04a0' 
  AND token = 'gtmFpMYLyT5BtUkeAyRgj7qrJL6vUpgdsm6ZoYcUogs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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