SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fcfb86afc2895650ed06231b105eed8822ab85c95bf7607946f8ff501858fdb5' 
  AND token = 'tAvR8ami1j4sonv/JapcQdEr6za85MSI/QDY8WGYsbA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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