SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60ef8dba3874e002da427f8037c8918c71338bb2cf5be223b330eac7bd040777' 
  AND token = 'wp7K1i2fZnmt1WxYNYmFkjufjhNT1R5x5gfpdrUelSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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