SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '678d0b532c7ad1e9ba9eb76ba1d40dde24cca98404b23c607cc672f31ed3fa99' 
  AND token = 'M2LhKFrzrvU8zlCj2+p0ea3UiVjUrawT29aiT9k+Fk4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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