SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c45edd3c2ad65fbfcbce82c4a1c4a6012f7d1bf46f6becdf37640564ae48e9a6' 
  AND token = 'f2qhg7qk3pf/4/u/0D9pFWAyU8C0J3wh2SWJCm4Uocc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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