SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '17295368f5ea10428fb337def1334636d0194ae86f3b3529c675bd5a346fdd03' 
  AND token = 'pD42gx6lGQXhmPtxMHGIzopxujJbLJ+9qh2hByMwiTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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