SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8944725f701eb91aa51ca12611df4a5ab1bb5900eded201ca4d15ec92a893cd7' 
  AND token = 'oQAx4WdxyYml6NBpVZTo7i1QPBPWN2i4d6HVYtIo23w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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