SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d575e724c9491a7341726cb08e76093ae65577aa76dbf81afd8ca4895bc8938' 
  AND token = 'NqFPx7yVEJaSsTF3/6+r62EJ5OIlY0pDneJ/NKgzZfI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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