Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0e88d4b21105078966b5fcc28da6718eef1b75192fcc91fdc1c713f2856068c' 
  AND token = 'E4OsXAdzghpp1Ls6lhuT+BpwLUopkP2HtcqCg+KnRCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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