SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f0e22725fb49eadafd69647563857bcaaac59154f09bcf5ea1603c830599936' 
  AND token = 'B9p9ExZJPMFMJgZpXtXzsYclkun2sLX4N/MfUX09eMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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