SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1b0becd5fb5fad6126ddda225ce60f5adddc0e54cd74979c9fcd54278bb10a3' 
  AND token = 'S91vpCWWOMVEXR+rndP3Fy2G2IoPvsmcA37m+V6CbSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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