SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8636236a4aa25c8d438d59e745e94b433c83b646cc5aa9800fc9478f227b7fd9' 
  AND token = 'wC+WHZPyFmpH4o9fdQAQYJAnIOQcTgzNco4BIwJQfKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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