SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1432adf3b73f5dc65af913d06cc8f0f1fd76275957443c4f6892c4601b43bbef' 
  AND token = 'Zj20vDUtSBBtQsD2Up4R+TQNhTuXj1ay2ywdWCjhQLo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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