SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca8e5b7af2dbaf479ebe94595bf0897482612235f2c5b47a03560c1a7e0cb90e' 
  AND token = '3DZWBfWQB6EZYLh3Kgmnvg3JXZeBRelfcQPCzXfVpIk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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