SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f5506696a239468f68e3bd5d705ce2c5034d85c168204a3a944884a0451e2f26' 
  AND token = 'WM0mDZLsvQlufaIrMOBPCvxiHgHPLsKyqN7NrMETPig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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