SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6cc3b80e057f954705262ee2083f7ed0bf2ea514610e6f92cc0784f366677fb' 
  AND token = 'ghloAbGygAL0PehE3Tl5smI9bKsJMDpv8T/dc1VnET0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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