SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd6c41df8be356807994bb3272c205bb156cf61cd98910f9dcea653ed7a61aa32' 
  AND token = 'ySHoS/vd8hkPlCTaV0DEcwItmvrwkMmcPO7v+P36lHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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