SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4cc6ad5c9fe97e13380a3e2d96f639e8bfa380af761cfd5cb50cd980de3bc369' 
  AND token = 'fvQJLOc7adV9TrbAWBTx5oMnvD+rW+scMJF3fwhZ58M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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