SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32d6565800ac00c3871691a0b33492957335dd79b9c815523d67fd621d0b4f1c' 
  AND token = 'SxozY7+UhgDXBXHbSPhfNnV5WE45YKTthwNA2ZvaJgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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