SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d6bf03a687ffe592ab6eff3520ca21b5fb7892dd449981aa6cf10478f700982' 
  AND token = 'KoUkaO240tFuNUlGHvKBiP9afs7o3THmIRvoToo0/dI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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