SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cb841ec954fca69b6b25c54946deb86abcd6f208b80013e1b5046891c628177c' 
  AND token = 'BDKIaasYqT75nwtUlgs0ycHXgnkFt621pLp74GHVVgI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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