SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a846d3b1f1870dc76a3e3476c6dc5e71d4c1e11c3515fd7822bf904780b328d7' 
  AND token = 'bFAZjufV2RfKggR33ZdGSXx7lwhA9TZ0VXHTNwqLzZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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