SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d95489e46921e38fbfa786ca09c7b8371a575ea80b86f306b27eda00ec58c02' 
  AND token = 'yhFn5v+bvorTzmwuSpSNYuHQCG02wyCoqrv/8yPgyBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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