SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbae45eeb11fbadac404cffee62201ae98045772c79b35da7f56ca7c929551ba' 
  AND token = 'lNnz/PurwrZt676KSWQfcjkA2HjQNPPJbd7DnUTrLDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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