SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b05fd079736318483ead54c29f2dc5b458b815f0a41d6b9d8a7fc752321ec8c' 
  AND token = 'iTMBPxMjp/AHBnQI8728Ycm9cYXqr0C57C4LM7/b3kc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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