SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5a7b26027103b17d537dd78ff9ae12422d57937e74efbb03aebda3dd0736688b' 
  AND token = 'B8lEg/+/jzEKktCf7w6mDYZ5sgTvvyHOouTpY8MWCyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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