SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8577fcb7aa4658ecdb93e8be80b8b2db8a98b97c06bc540438aa459155c761f8' 
  AND token = 'Z6HvBkDdN5wahsU1x4hIuM/LkjVrtaIXKc/Yk0GQvXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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