SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bbae316ef68a491de21a169860dea719796a51f8431785c359fb9ec1f91fe92' 
  AND token = 'kAPp6IsR0dwoCZMtc5PU7rVAU+J0/a7AWeZGKzi/fRs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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