SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b365e64ebf882a6557eac409b098f30cf5ba02e2c311b23542c91bb0d8f32386' 
  AND token = 'ufSms03pcus4r/CSZNNxmbPTCMhQtTppC3uJMAxlGKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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