SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48701341886d8fd7ba0fadbdd4f9f33668d44098e1ea0bd110085827610ba4e7' 
  AND token = 'biC+ZT6K6mx3aNSBAhN6vTjCa6HbIERK+45+TpDovuU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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