SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fbb212cdd886b80903c49db464d697a17360493e67c1c183896a57645534cb7' 
  AND token = 'uSHyYkFjCaWIp6W5RLyzVBXP+BUo84aVhaz4vA9ypfI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}