SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca83b1a58a708e3be077ac0db9f420861a8d55546493fac4868bf8edcb19ff77' 
  AND token = 'EQWpiKffAEh7w6PnIU8QTAqK0ncnIIdt1IV21xfYpXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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