SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c36ff30f7d7b58fb66223d3cbe0ab1fd010506a8251104201ab5ec1e67af6d24' 
  AND token = 'ZRFxClI1WwSKqYwCvqp799kAtQFE0uPYPIgDjiRIV8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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