SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed56cd4daa4a8a6d7d68eac54766c540836e962c78de4830e8db5575f8747f01' 
  AND token = 'MsKdEBo8sGKw320rMNbqELtN54nMdze5pZJCrL14X/U=' 
  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"
    }
  }
}