SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ec074fbc39dd97d61f3dbd9bbaac05a3af28f26132076d24f133c20b4ce32d0' 
  AND token = 'bZLKYhGnNqudhxJ+Mq2jY+rTCyYOqMTw+AvACe+A5o8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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