SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ced0ac1fcc43e05c77502a7c6c5d8ea9f340ae41f0e5e329a9bce5657f67a2c8' 
  AND token = 'LgIOLy59XyxZbnlc34XwwhsvvRJeQuYjIa9Lpan6kJE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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