SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2332bb6c209dbcece1d5d0cb59ffaffa8af2ba33c14659c3159897f6719da49c' 
  AND token = '2EqihwsnCe/N/c3RzsxYTOYnVQ6lC33Xs4xcSsV8dsM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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