SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dacd4d0d928621a51e96619ae32521ea5c0a25263e8924c22e1d9f1529ae6ba7' 
  AND token = 'CYknrLkrheRxUtIT4eMIPNQnA+qlO0tXtB5oS2msXvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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