SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf95cca7167a78349f16260f396ec59970d57654c026af2820d5610a0ba87d57' 
  AND token = 'QBPnL17oRF8cML6Qx8bmDpzCOdEgioKlYqr00wIC7Po=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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