SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '825677e3b495ff093f8cc9494a9ea074e6fd65b5c44e1ac33f61cc579083d4a2' 
  AND token = 'Ay7KxonNnCfmO24RQRdoXq8offnNKFWnfqFElifSUFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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