SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b399a6c8560985dce2c6cefe1f464dcbb164c207e1543fab51060c7c6fd7ede2' 
  AND token = 'oA03R2mP44JUiUYv7ZBb4VQa35sty8PuQCgBmjgZVp0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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