SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3e5dfb4fafe66905c83e2dc082d1f9523f38020f768f953ee96f249af8fade5' 
  AND token = 'Pedw1qMu+gpNBT/POM5DmUTfxrwa8YGGYROdmWcE2no=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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