SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7115dce68eb7a51ba9b2cfc880ea66c7276ab2d2412a2feb962eed310940b78e' 
  AND token = 'kg3HL0mZH6c4pBcCwyI0OBTf0mFIBlEKXHgL+jGobFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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