SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02f4c2deb1945d845154ba4dcb1e4c18fdccfdb825c2db97c3f659899823dbfb' 
  AND token = 'RT6dDZpnAyvhgEkL+wi5RkzFneecxW54YjI5fcRCvsk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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