SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18433ba1b7cdf9fe00a683272cadd9c07087ced093a28d9fbaac98ddb4feae02' 
  AND token = 'qSL3Y65IwWpwk2brvGeaXB5WBqTdAHWesSkPml6hCZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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