SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd60636f55990693d0676ee0c89f29616e7f7ba67251fac68d661f849850854a2' 
  AND token = '57JeWXsZtJweaLfG6FAodWBYOHQH4n6KA+raeUtlkyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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