SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c8d9bf9dbae5342d98298a48c67bb73f0af8c39c8114bd085d97caf4fcdc5ab' 
  AND token = '3ryhpgFQYtEbFhLIk+4JDDtFUVzK9+HsvYvbHzxFIqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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