SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e899c1aabe0c7e34228643221df86dc5c273644647cb06773e94d244810c0e2' 
  AND token = 'iUiPYlIbqtZzqtwaESiBT7DqaNYvE1o8a7xDGKpnadw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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