SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eac197a204e4040b598318d818611e3ae592b6d4c97b51bf739f177de00e338d' 
  AND token = 'WFiGo4EKqBwXe6wILMmVFWB+Xcd+IjWxXKAZ/f3hcyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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