SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0c14aff3184f69132eef8b36698d97ff9889cdb77d351a38378f45d6c653ce9' 
  AND token = 'hzQCu4mAHDxfqJYBEPyPNIU+ZPw4mVeAvoFW0qFgCAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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