SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5b35485e471a386a9ca3afebd56951f45424345087575309d67b5d36f77fd6e' 
  AND token = 'M8nWRM66O5melRoUzFkyNiPHpESao7t/DQmvXZ0AQsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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