SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d5ba317346266da7210827d2024aab46ca49e80ddb4110f8b6477d1f30336e7' 
  AND token = 'ZVAHjS0J/ek77KylRspM/ds7VenBtSx3J1W5qhQ1kyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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