SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fd6403ecd060a14f8e7a3b224f511415133a397f9538e01da6232851799bfa2' 
  AND token = 'qPJkd3bFl8zURlpXrYmfO6RTpQwucCEc6sbshQ37bGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00101

JSON explain

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