SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7ec5f8445df0175949307305b998ee07449ba5da247333e42885db468bc574c' 
  AND token = '/H8ROpnS9ljY3CUwyBRFSmpvhb3FDqr64uwoAXfWBws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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