SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b82d35cd3a14bbbdf5fec7e108701a6478443474221d129ad6fdc733920ce25' 
  AND token = 'FwIjX5dcnfc1XmA2wjxOdIQPEZ14gFSLka5DxPkfXAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}