SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e73cec8f5f7d123f5f2071f0dc41e1708311ab71c9ff3d046055cb5250a4e26' 
  AND token = 'CfFyD6VXdQY6O7egcVqu1DTo5RCOAf/IA1jQ9oq9hyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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