SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c329823bb82fa56f8a81862a4660dac69d0c8674dc0a6a5b7183c291394eb117' 
  AND token = 'Td0HzIw83uni29SaYbKC7kK8eOCtMxAiu6pI4hPbDVY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}