SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fc475decdf7d4dc0e4142e9cf8d6b7c0c4ab73b54d24e4ffa421235b24dadf1' 
  AND token = 'RjFf39biynODsNJsmSduAkZMFplMLiIZe1Qs5AxxVNc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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