SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a74ff98e5f1de55d34280444de5fa3a6df8f3826a73169ecf97f657c06d7ab6' 
  AND token = 'BcK0813mGzNzv3VYlSCX5zxf/4jKwCxBhQESTwMTGzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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