SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a3c94380e755d9efa555c03649efcf5ca57e6f6b3015101a4f2cbade8529f95' 
  AND token = 'mx+vDlyAVazUO7LRR6KUP4yi7phrv0ccnse1HzeIEnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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