SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '659c2c47ad869771c5254f99656c6b93363d716910dee76823929826b6e0b72b' 
  AND token = 'u8v7GqF1MdhjBavNkvKpHdGhWchCgdzYJVczeSkITPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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