SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77856ada9b8f3d6289411aa052bba384a245fc24d21d59e66b14f78a7aba86f5' 
  AND token = 'prCILnALfZE0PcIT4ldILCTWLhbxJrZgIVCmhKvkwzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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