SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd2fd5070237d18bc8b81788345ae57664ecbd1154f94efa40111eba937289d1' 
  AND token = 'q7om/peMwsUQFqm6f6JzjCO18la+EaDKy5IrpzTCjVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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