Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e98e4d5e83bd8142cc00f61258cd33ba2097eeba8fb2bc4c82242fdd9da9f6ec' 
  AND token = 'nK0MFh+TZfQNXR7tjfdvc3wyHpI7plDHBeo+97TkEbk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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