SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c3da69d3cd06bcd7b9da82b0805227a37886608716bad8596e46371ec4df30f' 
  AND token = 'jFx47UI+I053O6cOgW2KpTNSN/oOiGQmaxvKHoVucnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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