SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14df48063019a00cec8460ace0ced87cbddd1147e218be404ee2b165bb9665b7' 
  AND token = '1GgmH4EyEitmH8z7ChYggQ/7im/8PWxgPjnSuNHki6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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