SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59bb0a7ef9a02bbcba0b301d400e9e47a6110acca7ccf6cadae860bfa69dec00' 
  AND token = 'Sx62EKLhyxLQJCrT5CYezXXMVYGrG9VKmqqDwt9mlZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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