SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3fbbe5701f585316bc7ef31dc644025ca2835b1a08103bd432188da3b575c35e' 
  AND token = '1gDNII+oFh7Ifw1c3HA4ZjQFUK1jeboA+qRvH5cCodI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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