SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc58d950085635b45f9c961af788925480c27078efacf492d413f4117d54326d' 
  AND token = '4jcO37XwVGHjnuBXEwqqnPIUWvv/HdkpXGLJJbVN/rw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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