SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e20c18b6c4d9d0b2ef419c9efd4c6346760bf0c7717111aa9ffa22d92888f30e' 
  AND token = '44zrEeTDjlVdsoOh+CBsbjBbzU/d8hCV07mn7hXiXwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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