SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0ef2c4115fb1f886354496ebfa6454f38cbffc3d4434135aad30b8713f3a0a1' 
  AND token = 'jyvK2FGPKjXx6fHn4KlDG10aXoZ/W698h+yxSUFrhk4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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