SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7addfe4e2514b3798ebdaf2be142c2ed0be31e35ec4678d21a6b2c345d0ff409' 
  AND token = 'XHNh0mxT8N49EGJhloOBqkW/RJjLXoemjKp0Yqut4PM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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