SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64a89dc25e56dc209228ca4dcb1a17075e0f215904f859d57013b5538584a67a' 
  AND token = 'PXbzJyOgqRwtotGyuhLn7RBHEQZ57sMYUQuj5lvpHKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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