SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cb95693c51d7543bd8b9ab79ddb965c96746e125dbfb65e94c23971842644019' 
  AND token = 'T9L1fhef5c39K6AUlJeVhJ9plmuZHlQdJ9lwaQuyYy0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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