Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '357bf02db1294d5af093a8cad17874b35d342d8e88e567520ef4bc68b6d8fb67' 
  AND token = 'Mr8Ujyx+mmuJcc7jIpu3ShVxFrOtceXg8cHZiptf+Ec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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