SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2dafa404686cf77c13994b7e732ff3e04c2bc3b24c0dbac067aac1dc0ee2aa7c' 
  AND token = 'LjqhraSvdI7vcVG3cQUxtk+w7mjc4y3dLT5ij1dOh/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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