SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2adae691d7e0411145d08f055ee5a97af97763da1e38d50eeaf901bd4af32084' 
  AND token = 'gn6OmzCvWDHtXIRbXvgUEt73tXY0Hth7zjYZeIgnOu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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