SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2ab0c414decd78a64008d494742c7fd88a33ba646ea75b09cded4bee388dfa3' 
  AND token = 'pfoUX3LpGjlA1ss8cXj0EI3e8nSivMPm9ZEkO4dQ98k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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