SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a028032cfa590dfb5778b892db0af22338846eade629c070d48e0ce8d4908abe' 
  AND token = 'YYVeIhDa0AVxln7BXrW+kq7xenxEokSSHteQz/3mnIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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