SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98a951203524474b6043f2afed916834c2c0ad5d6c70ac09dcbd472ffb7d195b' 
  AND token = 'qWniGSMV00IEgDSVKlWK5cbTvj7wmHZxwjuXFHckzDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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