SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98332eeb726723c386abfe1f71bb11e38ad054f3fa923e8da4de1807a63fdd45' 
  AND token = 'iJFsoiG3BXizbVQoGJsmRaJ7+Bqu6/+29EqiUUmFBoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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