SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41259d859bc2cba16180360733821a753c3a272b6a7b61c8687f6854fa3bcd30' 
  AND token = 'C8AbLVlWUhwWjNmZQ9hpOAPcYOZuuRRshIR1zZIUe3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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