SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e011b6d7bb7dd83bb1c4d1496e332782d959934e808eb27fe8be6d311265f043' 
  AND token = 'jpzf3u1sun/iENU/ZQs8yzMx1uERV15JH1etqvifKgw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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