SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd733a8e57639eba7150968e7f194fd2fae0f8e6e9a19c0407af356a5e45c3b42' 
  AND token = 'mscLKDQoS6P+ZZ2f+96572jm/d02GWh386HJ3iTWwUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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