SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac69b202acabb3dd57cbd40ee6858fe2d7ea81a5e8145eda7d3adf178b0d6f4f' 
  AND token = 'GLwJKE27/YwkQnjsRobwtBWQmd73Ex92fE8etl375Ys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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