SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8a59c3370de15d7308475b61b6d963a3a18256d0dc029262d4e0c6d2816f842' 
  AND token = 'laZyGiR6BaPo5gfTfFmNlz/Mr00Mv+wZoNrKXyCcPCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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