SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1241f17c7f492d73c494105ece7783fdc2030a2f45a9e52b3d10f8d724f8ae16' 
  AND token = 'E4ZqACYBWq+6ynfonHhaeMSlUWX2QirfcxsisFKEp20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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