SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e33417f1419cbd9d8e9770d48ee029123e0faa1e369ce18bebee5206577b388f' 
  AND token = 'axlvAJxnx7LKidKhhZ08oCForFJU2GEzYoThcQ67LWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}