SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e5b61f4214d0797d4ad030af5768d9bce75e284970c590f289f1c339162f891' 
  AND token = 'w8FZfYN76gLbe435Iz7ji4DHKcJ/H19/re2I3ChVvX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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