SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27252f920fc7d7842bc179d3e9c17c58e6fdbc4187beba9424c0a8b7eb29300e' 
  AND token = 'Lay8mTSQ58/JVuctHFVds6xjUhutNBlcPHmdJzsIVYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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