SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9790d701076a49446ede6bf8362f19c93ce995a1ca039cf089b081c41285f611' 
  AND token = 'i2JJI1ltidQgV467h1qSXX/Y9hd6mqNfLiC6vFLAmLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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