SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d65544582963055a749428fa9d178255e34c44c19096aa40faa7eb022800a85' 
  AND token = 'KbHfu4CjTZnlYVJVcM6S/N4CJ1gYTOgWSuezRr8klO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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