SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bfbd68b9014459888cc19fd898000733e2ad4b0d50093d57a0752510d63f3cd8' 
  AND token = 'IgV/r1sFyq4OyidXejI5sbEHo4nskT+dcPw6h23ahew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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