SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2013c5e9c1cb2c3cface6cf062098b366b5d81f7b445d3a363b3ee1456aad438' 
  AND token = 'O/lLBJ+/3kegSHNC6aNcdejPVFTVOEwARc8jN4u9cXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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