SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32739058476b729787c85569ac0dabde33d852f04fcfac07a623eb5a02cd89e3' 
  AND token = 'Kh6f+iRMZ/dpew2WQUwmwF4LERz+sG3fZDq56sNzyYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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