SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '66223af6c160584c67083a2371c7dad1886febea92f1b9e8f026939297f1a7a4' 
  AND token = 'KfoGYpOJlbAdp8w/YQ7YBtb8m3aItYct4x+O2ezln9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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