SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d86106ac2af568099385f25c71b8e2134e406deed67f54d38db47d5b2e67e52' 
  AND token = 'hiSVElLAWOt6LyTPRd3BleS4wSYUCFI4WEdXZLLyABY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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