SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aff2fd69ac374b8ec4a178dd6ce87d8d4565f4571139532a0ade5ef472908976' 
  AND token = 'SVjIoFiSyhXNOuuqt/LmIfS2MzshhFHPJxPdyI8vFBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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