SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '431cb7a1c0307760184c2010f5eaf855e45feb9de4040ff1b1987384e2b900ad' 
  AND token = 'yt4C+KZWASxp+FfADT9a82xrYIpiq/Zy7qXWxvsf/X0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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