SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14ad14d8d65ca5b99a2605d8b36717a078709bb232d64038ce2f3667596e2c40' 
  AND token = 'huxb4Ifn7BKCgQjB/E3KsfUp6nRTzJA+CVyRq5zAUqk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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