SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ed808f5c08deefd2ceaf5ab621be4069302753689f9429f1c250100659e2227' 
  AND token = 'Us1ue4ErOrroCbzCHeD0lOvqIW2MxAJP/FKtATbbpj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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