SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b06ed5c1c08b971d8e4454cb58e4b89a271d58dbe602ea646177d433ab361070' 
  AND token = 'nGR82RZsmqqexRdoRS279Cm03dMy8PA93hxNQlIVDN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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