SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e34035bec47c0d76cde8cd4c8ea0aba59a12d15e5166d1b7d7af0bf5e68c4604' 
  AND token = 'PyqptbOEK2AI1wInRdgzshyRyI0OscamMQMawC5qPgI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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