SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc3c8fe3d572d8329b53f3306644bc3ba2f538f0e7e095a9ab8e3176ef59dae9' 
  AND token = 'XP+FxvAB2XDovE2TNu6AcggDmhS2umf51zXQIwzTFkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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