SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c5843f13f8e3d4060ffff48336373ee7a87aca7211a721fe02fbdd57853a8fe8' 
  AND token = 'L5brUDbI0INz1R5MEybySu7wwAjzvySvwpwyxM6Dzdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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