Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f8592bfbe1a3fa37554717afcfa06d04d45e57f6d88b44e39313f7224b29dca' 
  AND token = 'DECZrj+2lE61orPySei0yuikmtpPlNwaLTAgg0MdtgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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