SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '430f0dec3c497b2f19de06bc795d7a5061ac9d6350e9d0a2578729874a112d2a' 
  AND token = 'ildDBX5VyQMJ8BR54zfPZ+lEtQiR1oKJglb8kYTVvjI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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