SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3395883b0fbbc2b64274983d5df05a73a426e7a72366693bfee6be2f03076141' 
  AND token = 'njPx/5MXbLD/+BbmWrES0Bgu1mH5ElvcXHKZRJc+8Ps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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