SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3f49c80af96a128ac2869b2aef1a50f1adbddb73fdfdcef3fa1c2c663891a8f' 
  AND token = 'ZPCsaaywho9hwk3IeFmwwhAkWS6I4m8QgrVYwxq3CsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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