SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf575d9cf2de05c6ef52f6343df999084c514e22c5f3ebd347075ab2f3d8bf0d' 
  AND token = '778KU0Jm9Khle5YadK+dtBTeX/2HdD2tcQXxMH7Yo0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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