SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c10a09bbfb78a4ac32c1a00b0d5e73ebbb545897c6300dc1cf3285edbb7d12ff' 
  AND token = 'KTXmOeaL8O4JmsvqbNhmnQ5s914hnirpGR3XVWXpts8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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