SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a7d4550d4e4fd51c947d61b6397d2ca1f4c844569aaa316616189fbc26001e6' 
  AND token = 'TL60jHsJGzWtDbYuLBV85ZCjjeBvPyX6gmOhx4WX34M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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