SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5717f955ddfbd792187bb718074d128024199e8aea2e40c7fd347de4acf180df' 
  AND token = 'EPm/Mn+/XGJomQ88ugk1NeXDx6DZHPVhVyraAAxE8ps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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