SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0f514210f6db6dc1fd07919206e1c152d8ea7182f6ae22c49170d589f6ef1ae2' 
  AND token = 'lEGPlm4wr8LoeYQeEzgUk/84avyLvzrL8HBBWDKURPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}