SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '244d2946c8b51cabb7804f0bd45bf617cac2d42d042789393fe8268b451c281e' 
  AND token = '7jjKwIrDttD6Tj2pMq8ryD8cEZ6X0Ej4A936XxQ4lyI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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