SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2edc5f65fe963d2efbb7ead4339af133b8a6567f90893c5148308c94618bc694' 
  AND token = 'iJXbBC5FUtWHyogYjDRsCxXrdcx+AEpweQ8GiRlDOfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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