SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d8fd41dc5c6b76c7970e5abdee90b0cbf0bb18c855ea5079ec3a91c9db609a8' 
  AND token = 'bmjrp5CKj8we2f8B8iMbR8ghkflKZl7ryHOpiBFsN0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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