SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '146cdbe71afdcb588a5dfedbed89ab0c5f51ca4d70a64759263ea85be1106143' 
  AND token = 'xF5imZDTpo/12HtvraMwFYdMlyFzpjl9C/Ir3x0seGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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