SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '196f619ec97354b00fbe2d91f7c144a53593c8f7c958bcde9e8f56a0dca13be3' 
  AND token = 'qIXkrckw5LuoI3sFEUOEDJ9XqFAW/u7v4v1LIG1MNSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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