SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '643f3582ed9a42d95d565f63579abd85f413be09f08325c635d46c86128cd7e7' 
  AND token = 'Cg6GSRtuzuN7RpqhCkkZ9CN8u3/QuykfN05vBCfcRhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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