SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb2d30ff479a436f45a8378bad2858d07cb396eb7604170462e13fb9019a15e2' 
  AND token = 'esu8Vtcw06S4FO1K8O7JZPMfKPCZ5ZgCD+l9KYQnruo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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