SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5e54734e98a0866b1cfb6dc34b1fb8e85c617994cc25618dc9f0c42c380c788' 
  AND token = 'SlCd8j9dMsrLzninhGyuFaHRINV39bOB+mlqsmG/7Tg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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