SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4de3fc742418fbfeacaa8d22bffb63f8e1b1ba58fe532973357db9b31356ee07' 
  AND token = 'OyRvX70hbI+mkKAWZCBE421S8bz7/xkZMcPzzZowRCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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