SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd607bc5872bc0a4b0ac4762f2dca3f70537852cbd8a682869e202b413e72165' 
  AND token = 'RYsPXMawnQHhbJGa4sRZFU6csCKUBW8fMSQbr4Bm3hk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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