SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e8912bede687b46aa1c453182d411315ac721476d66b5d81e491fe6342aa79b' 
  AND token = '5AdjyJC1JoGBRMBRfL7iHMZSkJaN9tuQ02UnXdWfXWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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