SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f32ad542c84b51ffe9c3218d79521f7305fba3ebacb8e52725088436bff8accb' 
  AND token = 'JPNbPg+TbCyvjsvX/liy1P3WaYPLtmtx1h4Yejd6W2A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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