SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc6243bcf998daef393258ecfa34ab7193b50f87fa908f6a5eb4aa046c144744' 
  AND token = 'VCJzKVRoEMemONUy6v/quAyHkZwPjp5BtfJu4cMcmLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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