SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fcf0da4912e01e9d3eab27e45721dd6bb4463f190d989d4bb0f849a213aa5c0' 
  AND token = 'DBrznN+Emn2cCyX+YkWeSjPs9WgoFuJnGL4Wjww+xjk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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