SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aabfa5643a1b7d5f30bfd33a671f15711f66363929561ba7a35f661977371b7a' 
  AND token = 'hC6okbR99vAIVATdcO+A2FdccG05iSFXsdiKzzMzFRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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