SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82a44b7fccb16eec15f8edc5e525e3ee59c0689b25357e2ac8f61e52dbd42713' 
  AND token = 'QqnuHhXXWgvE9eQ2dSIlC9SuV1jEO0rW9Sf/JNZTxA8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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