Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '232e1c3dfe404b0047e2e60841012ffc16e6328d538a49e5b1b0f9621aa587cf' 
  AND token = 'xkqHmiokCknkEgBb4OiPvUlprrj/T3RKMSpdzTZwny0=' 
  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"
    }
  }
}