SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c53d9b785bb2cc9bb22e568178cd020f8af4b3e0ce7e3893f960b85055a1e42b' 
  AND token = 'aQ3fx/IR9JQxf8txFjc4y0rcraTII674DUT0xxqIneo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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