SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1442ceba8e7e4f9c84c651539662838e871023b60659719fa3a0e8ae24b424c' 
  AND token = 'PuweWvygsDfOT7zwalhn2KAX58KssTCV6qar0iejnq0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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