SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59ef91ba7b8f455ee1cecfe849712a65b1de5853ddc3abbbe156010338db39c1' 
  AND token = 'phU83pKVqxQuzFqkyLU8RJikG3tIxAgongdBRVepEio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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