SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cd183e1754f11e7773e49152b057bf2b3d7168933221a057378d825ebafb262' 
  AND token = 'AGcevAB788UTns4/8iEjK1W2t6z34RJyHXurVme5wHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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