SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '931622df51350d25458471c790194e314ce6ddc30b815a6130146c1b178becce' 
  AND token = 'QVlNx22p/zcL4X+DciJvlzGwJlFkrw2rdEqJx3KEeOU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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