SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ce70f5765cacf41d792757924d3141716ba415e013ed232f7fe86cc942fb18a' 
  AND token = '/H5WBngBVSPFgllrxQkECnAjxBlKjgVOsdO1oyzky6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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