SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55885be424ac0f661e970c9e48866384355adc54d7a3277cb83cb0cde8531335' 
  AND token = 'hCSbVXyQWTRk5jODCRqYK0BgTBQutF7I+ugy+OnJSbI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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