SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'caad6577325ceefcf7750f0d941448431092442e12f6bef51b22b0e03f1cc519' 
  AND token = 'czBpDsEQPnhoThpBqGO4g7MWLU8CztcqpYiRZl3rk+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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