SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '135f7108e46a720b1405e443ea22919e2d8ad45f0117a9c615b30f437e054dc6' 
  AND token = 'beg9Cckk5V9/6SEdxlzl705sgZakeYLhqzMPHOnaleQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}