SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aae9123be04965e603311baaeb694a92f29cfac0c339ec6b996751f178296109' 
  AND token = 'MrpR8wZFexDdDELARNgAI5rofjurajYDjItkrWywvUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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