SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d4729bd3883f2e75a493876ff0dd66d896d22bcad7059bc3c56e43d07ae0755' 
  AND token = 'AskaGZCk5TxsfERl+HmCEZEYoje/gmFiC+jMt/Ozm0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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