SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb09dd254d663b8465a4457a194fc0bc129ca3f006cc20883a1a340823fca22e' 
  AND token = 'omSZTeFPDPBSo3CeajWyPnsuSqApfIMc5faLR3WauOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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