SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0c352a6747589a8cf89d5b6d72b8f299e3e44490547f64aee9a56c65e0b7ce0' 
  AND token = 'gjv4ej2rNHmkbVCpIFH5ZFh/XQyzSpIqjXMPQ9olP+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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