SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '977681fb6ffd7fb4b1f3701eaf7d6769152c7f4fa8b0924e40659a409d91b1f5' 
  AND token = 'Q/lUNAx4iK+6QhBavKbuVCtrjLEwAUEfitPC+3Ypd/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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