SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba32998f56edfb5aa7ce594849345b9be0b11a92a5882cbb604111427884334b' 
  AND token = 'EabfwEc7WEMgZiWO45KdRDgCEbp6rBaJAgqewPOBvQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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