SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09786459e1fe9573607d890893dacfccd2c7004ff3e10d34b4582b30e7b7608a' 
  AND token = 'W66hbPowgpH2LkmVDGJwC97oXEFad3J9FqJ2i1xuGDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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