SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '727499f995fa471381ed39c139f8645234cd784c02304ac115030e8416b4773b' 
  AND token = 'DOPlujl8SgesUlS44D0NbuGmf0NVTfsOEl8nMEP0IDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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