SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c48a0b85e5adcd973d77b87aac9ed7fb2cc845c1b622c8fb68b81cf39978524' 
  AND token = 'LPWIZUjiMiON083WNYKbzGSSiDSmE5whLS24CIFPDic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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