SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdc9475de2605fc507bf37055e1c6631e36961e9988ba03ed700f4f3f3373818' 
  AND token = 'Ic0a2ORYpY7R5rsemY5vL9PMy4n0YcW5LgIAOqJgpZk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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