SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcf89070bbb41f9532cb0b4d8bfd1bc0a0edd727bfc36e0a35f62a909f61867e' 
  AND token = 'Jh/uMdcZWu9ROAB+1miMRVLJVKR3bgsICGGniMT4AOE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}