SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d13055f77ef5dc04982d55f3efc11f9a8880d900c062f83e87f51bebe202838' 
  AND token = 'LVp7q3j6u+RMJLynpJ3BsKJstk3zS1ZZpmSg4sH4HHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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