SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4549d35daa11e54c0229c5bbf71af000c9395860d187e2e92640214f7cd557b5' 
  AND token = 'BDpzY+133YbsN5V/jkXDeLXPOdSMRd9Ddc6rttlhKDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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